Guidelines on Safety of Tower Cranes

Disclaimer

This publication is prepared by the Construction

Industry Council (CIC) to report findings or set out
the recommended practices on specific subjects for
reference by the industry but is NOT intended to
constitute any professional advice on these or any
other subjects. The parties using this publication
should therefore seek appropriate advice from their
professional advisers. CIC (including its members
and employees) will NOT accept responsibilities for
any consequences resulting from the use of or failure
to use this publication.

Enquiries

Enquiries on these guidelines may be made to the CIC Secretariat at –

Rm 2001, 20/F, Alliance Building
130-136 Connaught Road Central
Hong Kong.
Tel. no. : 3571 8716
Fax no. : 3571 9848
E-mail : enquiry@hkcic.org

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Guidelines on Safety of Tower Cranes

Publication No. 1
Guidelines on Safety of Tower Cranes

A. Purpose

This publication sets out the good practices recommended by the Construction Industry
Council (CIC) for enhancing the safety of tower crane operation.

B. Definitions

2. In this document, unless the context otherwise requires –

(a) “Competent Person” means a person who is appointed by a Specialist Contractor
to supervise the erection, dismantling and height alteration of a tower crane;
(b) “Competent Mechanical Engineer” (CME) means a Registered Professional
Engineer registered under the Engineers Registration Ordinance (Cap 409) in the
Mechanical Engineering or Naval Architecture & Marine discipline;
(c) “height alteration” means climbing of a tower crane or the addition or removal of
mast section to or from its main tower;
(d) “operation” means the erection, dismantling or height alteration of a tower
crane;
(e) “owner” means person or company owning a tower crane;
(f) “Principal Contractor” means any person who enters into a contract with a client
organization to perform construction work;
(g) “Registered Contractor” means a person whose name is for the time being on the
registers maintained under section 8A of the Buildings Ordinance and is appointed
to carry out building works or street works on a site;
(h) “Registered Safety Officer” means a person registered under regulation 7 of the
Factories and Industrial Undertakings (Safety Officers and Safety Supervisors)
Regulations;
(i) “Registered Structural Engineer” means a person whose name is for the time
being on the structural engineers’ register kept under section 3(3) of the Buildings
Ordinance;

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 Guidelines on Safety of Tower Cranes
(j) “Specialist Contractor” means any person who enters into a contract with a
Principal Contractor, or a subcontractor of a Principal Contractor to perform the
erection, dismantling and height alteration of tower crane;
(k) “Technically Competent Person of Grade T5” (TCP T5) means a person
possessing academic or professional qualifications or experience of building
works or street works that satisfy the requirements set out in the Code of Practice
for Site Supervision issued by Buildings Department for a particular type of site
supervision or management tasks.

C. Introduction

3. Tower cranes are widely used for conveying of building materials on construction
sites. Given that collapse of tower crane could result in serious threats to the safety of site
personnel and members of the public, organizations and individual responsible for safety of
tower cranes should take appropriate measures to assure their safety.
4. The Factories and Industrial Undertakings Ordinance (“FIUO”), the Factories and
Industrial Undertakings (Lifting Appliances and Lifting Gear) Regulations (“LALGR”) and
the Occupational Safety and Health Ordinance (“OSHO”) impose duties on stake holders
to assure the safety of tower cranes. Furthermore, the Code of Practice on the Safe Use
of Tower Crane has been published by the Commissioner for Labour under Section 7A of
the FIUO providing practical guidance on selection, operation, erection and dismantling,
maintenance, inspection, examination and testing of tower cranes.
5. This publication make recommendations on the measures for further enhancing the
safety of tower cranes based on the good practices suggested by the concerned industry
stakeholders including tower crane owners, specialist contractors and professionals. The
Hong Kong Construction Association and the Construction Industry Council Training
Academy (CICTA) also contributed on technical and administrative aspects.
6. While this publication does not have any legal effects, Labour Department has indicated
that it may take non-compliances of the recommended parctices into account in considering
serving suspension notices under section 10 of the OSHO to the concerned Principal
Contractors or Specialist Contractors. For the avoidance of doubt, notwithstanding such
intention, this publication is issued by CIC for reference by industry stakeholders only and
will not constitute professional advice on tower crane operations or any other issues. The
parties using this publication should therefore seek appropriate advice from their professional
advisers. CIC (including its members and employees) will NOT accept responsibilities for
any consequences resulting from the use of or failure to use this publication.

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Guidelines on Safety of Tower Cranes

D. Measures for Enhancing Safety of Tower Cranes

7. The following groups of measures are recommended for enhancing the safety of tower
crane operations –
(a) checking before erection of tower cranes;
(b) improvements of site supervision;
(c) qualification and experience of Specialist Contractors; and
(d) qualification and experience of Competent Persons and workmen.

E. Checking before Erection of Tower Cranes

(i) Pre-delivery checking

8. The owner of a tower crane should engage a CME to conduct pre-delivery checking
in accordance with the procedures at Annex A before the tower crane is delivered onto the
site.
9. As stipulated at Annex A, the CME should issue the following documents for the
checking –
(a) Report on Pre-Delivery Verification of Components with sample at Appendix A.1
to Annex A; and
(b) Report on Pre-Delivery Inspection with sample at Appendix A.2 to Annex A.

(ii) Checking of anchorage

10. The anchorage of the tower crane should also be certified by a CME using Form 2
prescribed in LALGR before the tower crane may be used.

(iii) Checking of supporting structure

11. Under clause 4.5 of the Code of Practice for Site Supervision 2005 issued by Buildings
Department, where a tower crane forms part of the temporary works which may have effect
on the permanent structure by way of overstressing or overloading, the Registered Contractor
is required to appoint a person whose qualification and experience are not inferior to a
TCP T5 to certify the plans, design information and/or method statement of the works which
are to be submitted to the Registered Structural Engineer. The person so appointed will also

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 Guidelines on Safety of Tower Cranes
certify the completion of works.
12. In other cases, the Principal Contractor should, before a tower crane is erected, appoint
a TCP T5 to certify the adequacy of the design of the temporary works for supporting and
anchoring the crane paying particular attention to the foundation set-up, wall ties, guy ropes
and sitting structure. The assessment report should be submitted to the Principal Contractor
before concreting of the foundation and supporting structures.

(iv) Derrick crane

13. Where a derrick crane is used to erect or dismantle a tower crane, the procedures in
paragraphs 8 to 12 above should apply. In particular, where a derrick crane is supported on
the roof, the adequacy of the roof for supporting the derrick crane should be assessed.

F. Improvements of Site Supervision

(i) Appointment of supervising engineer

14. The Principal Contractor should appoint in writing a supervising engineer with the
following qualifications, experience and competences to control, monitor and supervise
operations on tower cranes –
(a) an engineering degree of relevant discipline;
(b) not less than four years of related working experience;
(c) capability in administering the “Hold Points” on critical parts;
(d) capability in communicating with the Competent Person throughout the operation;
and
(e) capability to conduct a visual inspection on the parts of a tower crane to ensure
that they are in good working order before commencement of any operations.

(ii) Risk Assessment

15. The Principal Contractor should arrange to conduct a risk assessment in good time
before the commencement of any operation on tower cranes to identify the hazards inherent
in the operation and the hazards which could result from adjacent activities. The assessment
should be conducted by a safety professional (e.g. a Registered Safety Officer) and Registered
Professional Engineers with suitable qualification and experience in appropriate disciplines
should be consulted on issues related to structural and mechanical stability. The assessment

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Guidelines on Safety of Tower Cranes

should be updated immediately before the start of the operations to take into account any
changes in circumstances.
16. The Principal Contractor should formulate measures for avoiding the hazards
identified in risk assessment, or where this is not possible, devise measures for minimizing
their likelihood of occurrence or mitigating their consequences. These measures include –
(a) installation of fall protection system for workers working at height;
(b) suspension of work activities within an exclusion zone around the tower crane
until an operation is completed;
(c) provision of personal protective equipment such as protective gloves, ear
protectors and reflective vests;
(d) sufficient rest breaks;
(e) provision of proper safety training for Competent Person and workmen engaged
in tower crane operations;
(f) provision of adequate lighting between floors; and
(g) employment of qualified workmen and Competent Person.
17. Chinese version of the risk assessment report should be made available on site for
reference by Specialist Contractors engaged in tower crane operations.
18. The Principal Contractor and the Specialist Contractor should jointly prepare a method
statement in Chinese to define the procedures of tower crane operations covering –
(a) all measures for avoiding or mitigating the hazards identified in the risk
assessment;
(b) step-by-step procedures supplemented by diagrammatic illustration;
(c) highlighting of critical hazards and safety precautions by words such as “Danger”,
“Caution” and “Hold Points”;
(d) procedure and instruction on dealing with “Hold Points” of critical parts;
(e) procedures for avoiding hazards to site personnel working adjacent to the tower
crane;
(f) clear statements on the role and tasks of members of the working crew; and
(g) arrangements for effective communication.
19. The guidelines for preparing reports for risk assessment are at Annex B.

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 Guidelines on Safety of Tower Cranes
(iii) Pre-installation checking

20. The Principal Contractor should check the availability of the following documents
before proceeding with the erection of a tower crane or a derrick crane for dismantling a
tower crane –
(a) report on verification of components referred to in paragraph 9(a) above;
(b) report on pre-delivery inspection referred to in paragraph 9(b) above;
(c) report on assessment of supporting structure referred to in paragraph 12 above
where applicable; and
(d) maintenance logbook recording the maintenance and inspection history of the
crane.

(iv) Pre-operation checking

21. The Principal Contractor should make the following documents available before
conducting any operation on a tower crane –
(a) report of the risk assessment for the operation including the method statement;
(b) records of the qualification and experience of the supervising engineer and the
Competent Person responsible for the operation; and
(c) all relevant certificates of test and examination of mobile cranes and derrick cranes
used in the operation.
22. Copies of risk assessment report (including the method statement) should be distributed
to the Specialist Contractor who should be advised of the estimated duration of the operation
and the boundaries of the exclusion zone.

(v) Pre-use Verification

23. After the completion of each operation, the Principal Contractor should engage a CME
to conduct a thorough examination and a load test to verify that the tower crane is fit for
use. The use of the tower crane should resume only after satisfactory completion of the
verification process.

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Guidelines on Safety of Tower Cranes

G. Qualification and Experience of Specialist Contractors

24. Principal Contractors should only engage competent Specialist Contractors registered
on the specialty of “Erection, dismantling and climbing1” of the Tower Crane trade of
the Voluntary Subcontractor Registration Scheme administered by CIC to execute tower
crane operations. Specialist Contractors should possess relevant experience and sufficient
technical capability and engage Competent Persons and workmen with appropriate skills
and experience.
25. A Specialist Contractor should be able to understand the method statement for tower
crane operations and to explain the details to his working crew including a full explanation
on the risks associated with improper working procedures and those safety hints and
precautions set out in the warning/attention sections of the method statement marked
“Cautions”, “Danger” or “Hold Points”.

H. Qualification and Experience of Competent Persons and Workmen

26. Specialist Contractors should employ Competent Persons and workmen with
appropriate qualifications, training and experience for performing all operations on tower
cranes taking into account the requirements set out at Annex C.
27. The manufacturer or his local agent should organize familiarization training on tower
cranes for Competent Persons.

I. Summary of Recommendations

28. The improvement measures recommended in the foregoing paragraphs are summarized
at Annex D together with the implementing organizations and timeframe.

1
Code 4.1.1

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 Guidelines on Safety of Tower Cranes
Annex A
Procedures for Pre-Delivery Checking

Purpose

This Annex sets out procedures for pre-erection examination of tower cranes.

Engagement of CME

2. The owner of a tower crane should engage a CME to conduct a pre-erection examination
of the tower crane before its erection on site.

Provision of Documents by the Owner

3. The owner should provide the following information to the CME –

(a) origins of parts and components - written confirmation that all parts and
components are identical or equivalent to the tower crane manufacturer’s original
equipment parts and components;
(b) unique identification of parts and components - unique identification to all main
structural parts, motors, gearboxes and braking systems of tower cranes to be
used when referring to components in reports for inspection and testing, and
certifications for repairs and modifications. (A sample list is included at Appendix
A.1.)
Unique identification will not be required for pins and bolts used for connecting
main structural parts if systems are in place for separating those that have passed
non-destructive tests from the others. However, if the crane manufacturer specifies
any limitations on the usage of the pins and bolts (e.g., with useful life based on
the number of uses, etc.), unique identifiers should be provided.
(c) verification checklist – listing the main components making up the tower crane
to help in verifying that these main components conform to the manufacturer’s
specifications;
(d) relevant sections from the user manual - to demonstrate conformance of parts and
components with the manufacturer’s specifications;
(e) maintenance logbook - details of the most recent repair and maintenance work
performed on the critical parts as listed below –

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Guidelines on Safety of Tower Cranes

(i) main structural parts;

(ii) motors;
(iii) gearboxes;
(iv) braking systems;
(v) slewing ring mounting bolts; and
(vi) other information requested by the CME.

Examination by CME

4. The CME should conduct thorough examination of the critical parts of a tower crane
before it is delivered to the construction site making appropriate reference to the information
provided by the owner. A checklist illustrating the possible scope of the examination is at
Appendix A.2. As the checklist is for illustration only and is not meant to be exhaustive,
the CME should verify its applicability and validity by making reference to manufacturer’s
specifications and manual of the specific tower crane and other relevant information.

Non-destructive Tests

5. The non-destructive tests on the critical components including bolts and pins and
welded connections should be conducted by qualified personnel. All bolts and pins (i.e.,
100%) used for connecting main structural parts should be tested. Items with cracks should
be replaced.
6. The CME should prescribe the non-destructive tests to be conducted on welded
connection based on the result of visual inspection of critical parts. For critical parts over 15
years old or of unconfirmed age, the minimum amount of welded connections to be tested
should be 10%. A higher percentage may be specified by the CME where deemed necessary
(e.g. due to a history of cracking).
7. If cracks are detected on any component, then all remaining welded connections on
that component should be tested. Components with cracks should be replaced or repaired in
accordance with the manufacturer’s specifications, and should be examined thoroughly by
the CME.
8. All non-destructive test reports should be forwarded to the CME for review.

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 Guidelines on Safety of Tower Cranes
Appendix A.1
Sample Verification Checklist

1. Particulars of Tower Crane

Site details : Block 1, 88 ABC road, Kowloon Tong

Site identification : TC1

Make : ABC

Model : TX100

Jib length : 55m

Mast height : 28.2m

Hook height : 30.7m

Serial No. : 123456

Year : 2007
( Note : The checklist is by no means exhaustive. Owners should examine its
applicability and validity by making reference to manufacturer’s specifications and
manual of the specific tower crane. )

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Guidelines on Safety of Tower Cranes

2. Manufacturer Specifications

Tower top / A-frame

Tie bar Tie bar Tie bar

1 2 3 4 6 7

Counter-jib Jib Trolley

EFFFF Slewing ring assembly

Ballast blocks

Standard, K102 Hook block

Standard, K102

Standard, K102
Tower mast sections

Reinforced, K103R

Standard, K102

Reinforced, K101R

Fixing angles/
foundation anchors

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 Guidelines on Safety of Tower Cranes
I have verified that the following main components and critical parts making up the
tower crane conform to the manufacturer’s specifications as follows:

Owner’s Manufacturer’s
Item Main components Qty Main dimensions Year Remarks
identification code
1 Fixing angles / anchors 4 F1, F2, F3, F4 Q200 200mm high 2007 Non- reusable
2 Tower base undercarriage Nil
/ chassis
3 Tower mast sections 1 M1 K103R 1.6m x 1.6m x 5m 2007 Reinforced
high
4 M2, M3, M4, M5 K102 1.6m x 1.6m x 5m 2007 Standard
high
1 M6 K101R 1.6m x 1.6m x 3m 2007 Base section,
high reinforced
4 Slewing ring assembly 1 M1 S300 2007 Reinforced

5 Tower top / A-frame 1 T1 A202 5m high 2007

6 Counter-jib 1 C1 C204 12m 2007

7 Jib 5 J1,J2,J3,J4J6 1,2,3,4,6 10m long 2007

1 J7 7 5m long 2007

8 Ballast blocks 4 B1,B2,B3,B4 Type F 4mx2mx0.3m thk 2007 4 tonnes each

1 B5 Type E 2mx2mx0.3m thk 2007 2 tonnes each
9 Wire drum 1 WD1 Φ500mm drum 2007 Hoisting
1 WD2 Φ200mm drum 2007 Trolley

10 Hook block 1 H1 2007 4-fall

11 Trolley 1 T1 2007 4-fall

12 Telescopic cage 1 TC1 2007

Date of Verification: Signature:

Date of This Report: Name of CME:

Reg. No.:

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Guidelines on Safety of Tower Cranes

Appendix A.2
Scope of the Thorough Examination

Report reference :

Report date :

THOROUGH EXAMINATION OF CRITICAL PARTS

FOR TOWER CRANE

(Note: The checklist shown in this report is by no means exhaustive. CME should examine
its applicability and validity by making reference to manufacturer’s specifications and
manual of the specific tower crane.)

Thoroughly examined by

Name of Competent Mechanical Engineer (CME) :

Registration No. :
Date of Examination :
Date of This Report :

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 Guidelines on Safety of Tower Cranes
CONTENTS

Section Description Page

1. Introduction

2. Particulars of tower crane

3. Visual examination

4. Dimensional examination

5. Review of maintenance logbook

6. Summary of findings

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Guidelines on Safety of Tower Cranes

1. INTRODUCTION

This report presents details of the thorough examination carried out on the critical
parts of the tower crane before they are delivered to a construction site.

2. PARTICULARS OF TOWER CRANE

Tower crane owner :

Inspection location :

Site address :

Site identification :

Make :

Model :

Jib length :

Mast / hook height :

Serial No. :

Year :

3. VISUAL EXAMINATION

Visual examination was carried out to check and examine the state of the critical parts
listed in Sections 3.1 and 3.2.
(Note: Visible damage includes cracking, deformation, corrosion, wear and abrasion)

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 Guidelines on Safety of Tower Cranes
Critical parts Acceptance criteria Condition acceptable
Yes No Remarks

3.1 Main structural parts

(a) Fixing angles / foundation anchors No visible damage affecting safety □ □ _________________

(b) Tower base undercarriage / chassis

Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Connection pins / bolts No visible damage affecting safety □ □ _________________

(c) Tower mast sections

Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Connection pins / bolts No visible damage affecting safety □ □ _________________

(d) Slewing ring assembly

Structural frame No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Slewing ring mounting bolts No visible damage affecting safety □ □ _________________

(e) Tower top / A-frame

Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Connection pins / bolts No visible damage affecting safety □ □ _________________

(f) Counter-jib
Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Tie bars No visible damage affecting safety □ □ _________________
Connection pins No visible damage affecting safety □ □ _________________

(g) Jib
Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Tie bars No visible damage affecting safety □ □ _________________
Connection pins No visible damage affecting safety □ □ _________________

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Guidelines on Safety of Tower Cranes

Critical parts Acceptance criteria Condition acceptable

Yes No Remarks

3.2 Accessories

(a) Ballast blocks

Undercarriage / chassis No visible damage affecting safety □ □ _________________
Counter-jib No visible damage affecting safety □ □ _________________

(b) Pulleys No visible damage affecting safety □ □ _________________

(c) Wire drums

Hoisting No visible damage affecting safety □ □ _________________
Trolley No visible damage affecting safety □ □ _________________
Luffing No visible damage affecting safety □ □ _________________

(d) Wire ropes

Hoisting No visible damage affecting safety □ □ _________________
Trolley No visible damage affecting safety □ □ _________________
Luffing No visible damage affecting safety □ □ _________________
(Note: Acceptance criteria shall include any special recommendations from the manufacturer)

(e) Hook block No visible damage affecting safety □ □ _________________

(f) Trolley No visible damage affecting safety □ □ _________________

(g) Collars
Climbing collars for No visible damage affecting safety □ □ _________________
floor climbing
Climbing ladders for No visible damage affecting safety □ □ _________________
floor climbing
Wall tie collars for telescoping No visible damage affecting safety □ □ _________________
Hydraulic assembly No visible damage affecting safety □ □ _________________

(h) Telescopic cage

Structural members No visible damage affecting safety □ □ _________________
Welded connections No visible damage affecting safety □ □ _________________
Connection pins / bolts No visible damage affecting safety □ □ _________________
Hydraulic assembly No visible damage affecting safety □ □ _________________

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 Guidelines on Safety of Tower Cranes
4. DIMENSIONAL EXAMINATION

Measurement of the pin and hole diameter for pinned connections was carried out to
check for out-of-tolerance against the manufacturer’s recommendations.

Critical parts Acceptance criteria Condition acceptable

Yes No Remarks

(a) Mast section connections

Pin diameter As per manufacturer’s recommendations □ □ _________________
Hole diameter As per manufacturer’s recommendations □ □ _________________
(Note: Connections with fixing angles / foundation anchors, between adjoining mast sections, and with slewing
ring support)

(b) Jib section connections

Pin diameter As per manufacturer’s recommendations □ □ _________________
Hole diameter As per manufacturer’s recommendations □ □ _________________
(Note: Connections between adjoining jib sections)

(c) Tie bar connections

Pin diameter As per manufacturer’s recommendations □ □ _________________
Hole diameter As per manufacturer’s recommendations □ □ _________________
(Note: Connections between adjoining tie bars, and with fixing plate)

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Guidelines on Safety of Tower Cranes

5. REVIEW OF MAINTENANCE LOGBOOK

The repair and maintenance record prepared by the tower crane owner should include
details of work performed on the following critical parts.

Critical parts Acceptance criteria Condition acceptable

Yes No Remarks

(a) Main structural parts As per manufacturer’s instructions □ □ _________________

(b) Motors
Hoisting As per manufacturer’s instructions □ □ _________________
Slewing As per manufacturer’s instructions □ □ _________________
Trolley As per manufacturer’s instructions □ □ _________________
Luffing As per manufacturer’s instructions □ □ _________________

(c) Gearboxes
Hoisting As per manufacturer’s instructions □ □ _________________
Slewing As per manufacturer’s instructions □ □ _________________
Trolley As per manufacturer’s instructions □ □ _________________
Luffing As per manufacturer’s instructions □ □ _________________

(d) Braking systems

Hoisting As per manufacturer’s instructions □ □ _________________
Slewing As per manufacturer’s instructions □ □ _________________
Trolley As per manufacturer’s instructions □ □ _________________
Luffing As per manufacturer’s instructions □ □ _________________

(e) Slewing gear mounting bolts

Tightening torque As per manufacturer’s insxtructions □ □ _________________

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 Guidelines on Safety of Tower Cranes
6. SUMMARY OF FINDINGS

6.1 Critical parts thoroughly examined

□ All critical parts thoroughly examined are in acceptable condition, and are
considered suitable for site installation.
□ The critical parts listed below are not in acceptable condition, and are required
to be replaced or repaired in accordance with the manufacturer’s specifications.
The replaced or repaired parts are required to be further thoroughly examined by
a CME when they become available.
Critical part Details of non-conformance

(a) _____________ _________________________________________

(b) _____________ _________________________________________

(c) _____________ _________________________________________

6.2 Maintenance logbook

□ Record of repair and maintenance work performed on the critical parts is

available.
□ Record of repair and maintenance work performed on the following critical parts
is not available. When all the outstanding repair and maintenance work have
been performed, the relevant record should be updated by the owner and further
reviewed by a CME.
Critical part

(a) ___________________________________________

(b) ___________________________________________

(c) ___________________________________________

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Guidelines on Safety of Tower Cranes

6.3 Non-destructive test reports

(a) Bolts and pins

Non-destructive test report for bolts and pins used for connection of main structural
parts is available to confirm that they are in acceptable conditions.
□ Yes □ No
Remarks: __________________________________________________

__________________________________________________

(b) Welded connections

Non-destructive test report for welded connections is available to confirm that
they are in acceptable conditions.
□ Yes □ No
Remarks: __________________________________________________

__________________________________________________

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 Guidelines on Safety of Tower Cranes
Annex B
Report for Risk Assessment

Purpose

This Annex sets out the guidelines for reporting on risk assessment for tower crane
operations.

Overview

2. A report for risk assessment should consist of the following sections –

(a) introduction;
(b) hazard assessment;
(c) method statement;
(d) record of key personnel; and
(e) manufacturer’s manual for tower crane.

(A) Introduction

3. This section should cover –

(a) purpose of the risk assessment report;
(b) scope and detailed description of the project; and
(c) operations covered by the report.

(B) Hazard assessment

4. This section should cover the hazards identified taking into account all relevant matters
including –
(a) preparation work
• deployment of crew for work supervision;
• checks on the suspension points of various accessories (items should be
specified);
• checks on the lifting appliances and lifting gears (items should be specified);
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Guidelines on Safety of Tower Cranes

• operating frequencies of walkie-talkies;

• checks on hand tools and fall arresting stripes;
• checks on full body harness;
• location of the exclusion zone;
• checks on personal protective equipment;
• storage of material;
• safety training;
• wind speed monitoring and the maximum allowable wind speed; and
• arrangement of the control ropes;
(b) work commencement procedures specifying the potential risk and mitigation
measures of all procedures;
(c) work completion procedures including tests, examination and certification; and
(d) contingency plan for emergencies.
5. A sample hazard analysis is included at Appendix B.1 for reference.

(C) Method statement

6. The method statement should be drawn up in consultation with the Competent Person,
the Registered Safety Officer and other persons concerned and should clearly define the
procedures for every step of the operations. It should be issued to the working crew for
effective compliance with the prescribed procedures.
7. The method statement should include –
(a) details of the construction site and construction works including a site layout
plan;
(b) general safety measures for the works;
(c) pre-construction plan;
(d) operating procedures with key points illustrated by diagrammatic illustrations;
(e) personal protective equipment; and
(f) safety measures for the operation.

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 Guidelines on Safety of Tower Cranes
8. Example of a site layout plan is included at Appendix B.2 while a sample method
statement for dismantling of tower crane is at Appendix B.3.

(D) Personal particulars of crew members

9. This section should list the personal particulars of –

(a) staff responsible for drawing up the method statement;
(b) members of the working crew –
(i) Competent Person;
(ii) senior workmen; and
(iii) junior workmen.
10. Personal particulars should include the following –
(a) name of the person;
(b) position held;
(c) qualifications held (including certificates issued in accordance with statutory
provisions); and
(d) year of experience.
11. A sample of personal particulars is at Appendix B.4.

(E) Manufacturer’s Manual

12. Contractor should enclose a copy of the manufacturer’s manual in the risk assessment
report.

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 Appendix B.1

Guidelines on Safety of Tower Cranes

Report of Hazard Analysis for Addition of Mast to Tower Crane SAMPLE
ABC Construction Company Safety : xxxxxx
Revision : 3
Date :
Findings of Analysis into Works Hazards
Description of work : Addition of mast to heighten a tower crane Location of Operation :
Post of operator : Tower Crane Operator of XX
Members of Hazard Analysis xxx (Superintendent), xxx (Respresentative of XX),
: Date of Analysis :
Group xxx (Quality Control Manager) xxx (Chief Mechanic) and xxx (Safety Officer)
Reviewed by : xxx Superintendent (Vetting) Recorded by xxx (Safety Officer) Date of Review :
Personal Protective Equipment : Safety Harness NH60/Sala / P+P, Fall Arrestor FUJII DENKO, Mask 3M 8210 N95, Ear Plug 3M EP1250, Eye Goggles UVEX 9161-014, Safety Helmet Centurion 1100, Safety Boots
Required

Entities being Hazard

Possibility(P) Risk Level
affected Level(C)
Workers(W) Very Possible(5) Mild(1) Residual
26

Basic Operation Procedure Existing and Potential Hazard Public(P) Possible(4) Affected(2) Mitigation Measures Risk
Action
Environment (E) May be Possible(3) Serious(3) P*C Level
Asset(A) Slimly Possible(2) Disastrous(4)
Impossible(1)
(1) Preparation Work:
Item 1.1 Item 1.1 Item 1.1
Formulation of safe working Danger caused by non-specific working W,A 4 3 12 Representative of XX draws up works 9(3x3) QCM/SO
procedure on the addition of mast to procedure (potential danger: Danger triggered hazard analysis, risk control measures and Superintendent
tower crane because of no works statement was prepared or works programme together with QCM, /Chief
works statement being inappropriate) Chief Mechanic, Superintendent and Mechanic
Safety Officer
Item 1.2 Item 1.2 Item 1.2
Staffing arrangement for dedicated Unclear or inadequate definition by monitoring W,A 4 3 12 XX appoints experienced works supervisor 9(3x3)
personnel to monitor the addition of officer triggers danger (potential danger: to monitor all procedures of the addition of
mast to tower crane Danger triggered because monitoring officers mast to tower crane (the supervising officer
are not at site to monitor the addition of chassis is XXX/XXX/XXX)
to mast)
 Item 1.3 Item 1.3 Item 1.3
Examination of every hanging There is the danger that an accessory may W,A 4 3 12 Works Supervisor to check all hanging 9(3x3)
point (such as ballasts etc.) (It is fall during the process of hoisting. (Potential points are fit before assigning workers to
necessary to specify which hanging danger: defects of hanging points may lead to carry out proper hoisting.
points are included.) falling.)
Item 1.4 Item 1.4 Item 1.4
Inspect all lifting appliances and Hoisting may lead to the falling of materials. W,A 4 3 12 Works Supervisor to check that lifting 9(3x3)
lifting gears.(It is necessary to (Potential danger: hoisting danger occurs gears and cranes have been issued with
specify which lifting appliances and because lifting gears have not been inspected certificates of inspection and are in good
lifting gears are included.) by public surveyor or they are in poor condition before proceeding to works
conditions.) procedures.
Item 1.5 Item 1.5 Item 1.5
Frequency channel of walkie-talkie Danger occurs during hoisting of material W,A 4 3 12 Works Supervisors are responsible for 9(3x3)
and communication. (potential danger: poor ensuring the proper reception of walkie-
27

reception leads to danger.) talkie.

Item 1.6 Item 1.6 Item 1.6
Inspection of hand tools and fall Hand tools may fall down. (Potential danger: W,A 4 3 12 Works Supervisors are responsible for 9(3x3)
arrest strips such as tools slipping from hand when in use ensuring all hand tools are tied to fall arrest
may fall down.) stripst
Item 1.7 Item 1.7 Item 1.7
Inspection of full body harness. Potential danger of fall of person. (Potential W,A 4 3 12 Works Supervisors are responsible for a 9(3x3)
danger: irregularity of full body harness or pre-works procedure inspection to ensure
failure to use full body harness may lead to fall full body harnesses are proper and to
of person.) supervise workers to use them during the
works procedure. Also to instruct workers
to use the harnesses properly before any
works procedure.
Item 1.8 Item 1.8 Item 1.8
Fencing-off of site (It is necessary to Affect workers at lower working area. W,A 4 3 12 Foremen, Chief Mechanic and Works 9(3x3) Foreman
specify the location.) (Potential danger: danger occurs because Supervisor are jointly responsible for
of improper fencing-off of site or there are determining the area to be fenced off.
workers working at lower working area.) Works Supervisor is to send someone
to guard against workers of other trades
getting into the crane erection area.

Guidelines on Safety of Tower Cranes

 Guidelines on Safety of Tower Cranes
Entities being Hazard
Possibility(P) Risk Level
affected Level(C)
Workers(W) Very Possible(5) Mild(1) Residual
Basic Operation Procedure Existing and Potential Hazard Public(P) Possible(4) Affected(2) Mitigation Measures Risk
Action
Environment (E) May be Possible(3) Serious(3) P*C Level
Asset(A) Slimly Possible(2) Disastrous(4)
Impossible(1)
Item 1.9 Item 1.9 Item 1.9
Inspection of personal protective PPP cannot fully perform its protection W,A 4 3 12 Works Supervisor to inspect PPE before 9(3x3)
equipment (PPE) function. (Potential danger: improper PPE can assigning work and to instruct workers of
not perform its protective function or improper the proper use of it.
use of PPE by worker may lead to danger.)
Item 1.10 Item 1.10 Item 1.10
Placing of materials Improper placing of materials triggers danger W,A 3 3 9 Works Supervisor and Foreman to jointly 6(3x3) Foreman
(Potential danger: such as material obstructing work out the arrangement for placing of
passage, tall stacking and insecure placing, materials and to choose a suitable and
etc.) secure place for the placing of materials.
To instruct and supervise workers to place
28

materials suitably and less than 2 metres

high.
Item 1.11 Item 1.11 Item 1.11
Safety training Inadequate training of workers leads to danger W 4 3 12 Works Supervisor to arrange training 9(3x3)
(Potential danger: Inadequate hazard awareness for workers before works procedures
of worker leads to danger.) commence, including manual handling
work.
Item 1.12 Item 1.12 Item 1.12
Monitoring of wind speed (It is Wind speed exceeding 62 km per hour will W,A 4 3 12 Works Supervisor and Chief Mechanic are 9(3x3)
necessary to specify the greatest result in danger (Potential danger: The turning responsible for monitoring. (Receiving
wind allowable.) of chassis and insecure hoisting may result in weather report) when wind speed exceeds
danger.) 62 km per hour, operation of tower crane
should be stopped immediately.
Item 1.13 Item 1.13 Item 1.13
Arrangement for control rope Collision of objects endangers workers W,A 4 3 12 Works Supervisor to arrange adequate and 9(3x3)
(Potential danger: Inadequate and improper suitable control rope and monitor the use
control rope may lead to danger in hoisting.) of it.
 (2) Commencing works procedure
(Erection of telescopic cage)
Item 2.1 Item 2.1.1 Item 2.1.1
Use the tower crane and two long Potential danger of fall of person ~1 (Potential W,A 4 3 12 Works Supervisor to instruct workers 9(3x3)
chain slings and two short chain danger: As workers work on the mast of the to fix the full body harness firmly with
slings to hoist the telescopic cage to tower crane, there is the danger of fall of fall arrestor before starting the works
the mast at the bottom of chassis person.) procedure.
and then open the door of the Works Supervisor to check if the access
telescopic cage. After fixing it to leading up and down is secure and
the mast at the bottom of chassis, suitable.
use lifting gear to adjust the door
Item 2.1.2 Item 2.1.2
of the telescopic cage and fix it
properly, and then hammer the Potential danger of load falling down~1 W,A 4 3 12 Works Supervisor to ensure the hanging 9(3x3)
pins until they are firm, so that the (Potential danger: Inappropriate hanging point point is proper before assigning workers
telescopic cage is firmly fixed on the of telescopic cage or unsuitable hoisting device with rigging certificate and experience to
mast. Jack up the telescopic may lead to the danger of load falling down.) carry out rigging and lifting operation.
cage to the position of the chassis
and then secure the 4 pins of the Works Supervisor to fence off the lower
telescopic cage to the bottom of working area before works procedures
the chassis. After that remove the commence.
29

hook and connection wire.

Works Supervisor to check the valid
certificates of all lifting devices and to
ensure all lifting devices are in good
condition by visual inspection.
Item 2.1.3 Item 2.1.3
Potential danger of falling of tools~1 (Potential W,A 4 3 12 Works Supervisor to instruct and monitor 9(3x3)
danger: hand tools slipping from hand may fall workers to use fall arrest strips to prevent
down.) hand tools from falling.
Item 2.2 Item 2.2.1 Item 2.2.1
To install two mono-rails at the Potential danger of fall of person~1 (Potential W,A 4 3 12 Works Supervisor to instruct workers 9(3x3)
bottom of chassis and use the tower danger: As workers work on the mast of the to fix the full body harness firmly with
crane to fix the trolley on the mono- tower crane, there is the danger of fall of fall arrestor before starting the works
rail. When the telescopic person.) procedure.
cage is installed at the bottom of Item 2.2.2 Item 2.2.2
chassis, lift counter-jib to balance
the tower crane. Potential danger of load falling out~1 (Potential W,A 4 3 12 Works Supervisor to ensure the rigging 9(3x3)
danger: Inappropriate rigging method of mono- method of mono-rail is appropriate before
rail or unsuitable hoisting device may lead to assigning workers with rigging certificate
danger of load falling down.) and experience to carry out rigging and
lifting operation.

Guidelines on Safety of Tower Cranes

 Guidelines on Safety of Tower Cranes
Entities being Hazard
Possibility(P) Risk Level
affected Level(C)
Workers(W) Very Possible(5) Mild(1) Residual
Basic Operation Procedure Existing and Potential Hazard Public(P) Possible(4) Affected(2) Mitigation Measures Risk
Action
Environment (E) May be Possible(3) Serious(3) P*C Level
Asset(A) Slimly Possible(2) Disastrous(4)
Impossible(1)
Works Supervisor to fence off the lower
working area before works procedures
commence.
Works Supervisor to check the valid
certificates of all lifting devices and to
ensure all lifting devices are in good
condition by visual inspection.
Item 2.2.3 Item 2.2.3
Potential danger of falling of tools~1 (Potential W,A 4 3 12 Works Supervisor to instruct and monitor 9(3x3)
danger: hand tools slipping from hand when in workers to use fall arrest strips to prevent
use may fall down.) tools from falling.
30

Item 2.2.4 Item 2.2.4

Potential danger of fall of ballasts~1 (Potential W,A 4 3 12 Works Supervisor to assign workers with 9(3x3)
danger: Inappropriate rigging point may lead rigging certificate to carry out hoisting
to falling during hoisting) procedures.
To instruct worker of the proper rigging
method before works procedures
commence.
To ensure rigging operator possesses
relevant crane operation certificates and all
lifting devices are in good condition and to
check that they can be used.
Potential danger of fall of ballasts~2 (Potential W,A 4 3 12 Ganger to check that the hanging points 9(3x3)
danger: inappropriate hanging point may lead of ballests are proper before hoisting them.
to fall during hoisting.)
 Works Supervisor to ensure chain slings
are checked and are issued with valid
certificate and are suitably locked before
assigning experienced workers with rigging
certificate to carry out rigging procedure.
Item 2.3 Item 2.3.1 Item 2.3.1
When the tower crane is balanced, Potential danger of fall of person~1 (Potential W,A 4 3 12 Works Supervisor to instruct workers 9(3x3)
hammer out the 8 pins at the bottom danger: As workers work on the mast of to fix the full body harness firmly with
of the chassis and jack up the part of the tower crane there is the danger of fall of fall arrestor before starting the works
tower crane above the chassis person.) procedure.
until the two temporary supporting Item 2.3.2 Item 2.3.2
wedges can be laid on the shackle
of the mast, and then slightly lower Potential danger of pin falling out~1 (Potential W,A 4 3 12 Works Supervisor to instruct and monitor 9(3x3)
the tower crane so that it is firmly danger: Inappropriate hammering of pin or worker to hold pins firmly before putting
supported. Use hydraulic jack to unsuitable hoisting device may lead to fall them in the correct position and to start
jack up the tower crane. Use down of pin.) the procedure of hammering when they
tower crane to hoist mono-rail to are firm.
the position of the mast and put the Works Supervisor to fence off the lower
mast into the telescopic gear. working area before works procedures
Hammer the 8 groups of pins at commences.
31

the bottom of chassis until they are Item 2.3.3 Item 2.3.3
firm enough and then hammer the 4
Danger of tower crane falling~1 (Potential W,A 4 3 12 Works Supervisor to check shackle is
groups of pins joining the mast until
danger: Inappropriate installation of shackle properly installed before assigning workers
they are firm enough. The
may lead to the fall of tower crane.) to commence the tower crane telescoping
telescoping procedure of tower
procedure.
crane is completed.
Item 2.3.4 Item 2.3.4
Danger of tower crane falling~2 (Potential W,A 4 3 12 Works Supervisor to check the wedges are 9(3x3)
danger: Inappropriate installation of temporary properly installed before assigning workers
support wedges may lead to the fall of tower to commence the tower crane telescoping
crane.) procedure.
(Dismantling of telescopic cage.)
Item 2.4 Item 2.4.1 Item 2.4.1
When the tower crane has climbed Potential danger of fall of person~1 (Potential W,A 4 3 12 Works Supervisor to instruct workers 9(3x3)
to the appropriate height, lower the danger: As workers work on the mast of tower to fix the full body harness firmly with
telescopic cage until it sits firmly on crane there is the danger of fall of person.) fall arrestor before starting the works
the mast, and then hammer out procedure.

Guidelines on Safety of Tower Cranes

 Guidelines on Safety of Tower Cranes
Entities being Hazard
Possibility(P) Risk Level
affected Level(C)
Workers(W) Very Possible(5) Mild(1) Residual
Basic Operation Procedure Existing and Potential Hazard Public(P) Possible(4) Affected(2) Mitigation Measures Risk
Action
Environment (E) May be Possible(3) Serious(3) P*C Level
Asset(A) Slimly Possible(2) Disastrous(4)
Impossible(1)
the 8 groups of pins at the bottom of Item 2.4.2 Item 2.4.2
chassis and dismantle the telescopic Potential danger of pin falling down~1 W,A 4 3 12 Works Supervisor to instruct and monitor 9(3x3)
cage with the following procedure: (Potential danger: Inappropriate hammering of worker to hold pins firmly before putting
1. Use wires to secure the gate of pins or unsuitable hoisting devices may lead to them in the correct position and to start
the telescopic cage and dismantle danger of pins falling down.) the procedure of hammering when they
the gate. are firm.
2. Secure two groups of two long Works Supervisor to fence off the lower
and two short chain slings to four working area before works procedures
appropriate positions and hammer commence .
out the four groups of pins each at Item 2.4.3 Item 2.4.3
the chassis and the four corners of
Potential Danger of telescope cage falling ~1 W,A 4 3 12 Works supervisor to check the mono-rail is 9(3x3)
32

the mast.
3. Use wires to secure the telescopic (Potential danger: Inappropriate installation of secure before proceeding.
cage. mono-rail may lead to falling of the mast.)
4. Retrieve the shackle and loosen Works Supervisor to fence off the lower
the hydraulic jack. working area before works procedures
5. Use chain slings to pull out the commence.
telescopic cage along the mono-rail Works Supervisor to check the valid
and hoisthe telescopic cage back to certificates of all lifting devices and to
the ground. (Remark: Other method ensure all lifting devices are in good
of dismantling the telescopic cage condition by visual inspection.
can also be used.)
Works Supervisor to ensure the telescopic
cage has been secured with wires.
Item 2.4.4 Item 2.4.4
Potential danger of falling of hand tools~3 W,A 4 3 12 Works Supervisor to instruct and monitor 9(3x3)
(Potential danger: when tightening bolts, there worker to use hand tool and control rope.
is the danger of hand tools or bolts falling.)
Works Supervisor to fence off the lower
working area before works procedures
commence.
 Item 2.4.5 Item 2.4.5
Danger of tower crane falling. (Potential W,A 4 3 12 Works Supervisor to check pins are 9(3x3)
danger: Inappropriate installation of pins may properly installed before assigning workers
lead to falling of the tower crane.) to start the tower crane dismantling
procedure.
Item 2.5 Item 2.5.1 Item 2.5.1
Transport the hydraulic jack and Potential danger of load falling down~2 W,A 4 3 12 Works Supervisor to ensure the hanging
tools etc. back to the ground (Potential danger: Inappropriate hanging points for the hoisting of hydraulic jack and
points for the hoisting of hydraulic jack and telescopic cage are proper before assigning
telescopic cage may lead falling.) workers with rigging certificate and
experience to carry out rigging operation.
Works Supervisor to check the valid
certificates of all lifting devices and to
ensure all lifting devices are in good
condition by visual inspection.
Works Supervisor to instruct and monitor
workers to use skip that have been checked
for bulk handling.
Works Supervisor to fence off the lower
33

working area before works procedures

commence.
Item 2.6 Item 2.6.1 Item 2.6.1
Assign competent examiner to Potential danger of fall of testing block~1 W,A 4 3 12 Works Supervisor to assign workers with 9(3x3)
the site to carry out the tests and (Potential danger: Inappropriate rigging may rigging certificate to carry out hoisting
examine the tower crane. The leads to falling down during hoisting.) procedure.
tower crane can only be used after Works Supervisor to assign workers with
electrician has adjusted the safe rigging certificate to carry out hoisting of
device and CME has issued a valid mast.
certificate.
Before the works procedure is carried
out, instruct workers of the proper rigging
procedure.
To ensure crane operators possess relevant
crane operation certificate and all lifting
devices are in good condition and are
checked suitable for use.
Potential danger of fall of testing block ~2 W,A 4 3 12 Ganger to check that hanging point of 9(3x3)
(Potential danger: Inappropriate hanging point the testing block is proper before hoisting
may lead to falling during hoisting.) them.

Guidelines on Safety of Tower Cranes

 Guidelines on Safety of Tower Cranes
Entities being Hazard
Possibility(P) Risk Level
affected Level(C)
Workers(W) Very Possible(5) Mild(1) Residual
Basic Operation Procedure Existing and Potential Hazard Public(P) Possible(4) Affected(2) Mitigation Measures Risk
Action
Environment (E) May be Possible(3) Serious(3) P*C Level
Asset(A) Slimly Possible(2) Disastrous(4)
Impossible(1)
Works Supervisor to ensure chain slings
are checked and are issued with valid
certificate and are suitably locked before
assigning experienced workers with rigging
certificate to carry out rigging procedure.
(3) Completion of works Item 3.1 Item 3.1
procedure Fall of object (Potential danger: If tools are W,A 4 3 12 When the works procedures are completed, 9(3x3)
not properly put away, and a tower crane is Works Supervisor to check that all tools are
in operation, there is the danger of falling of put away properly.
object.)
(4) Emergency Item 4.1 Item 4.1
34

Fire breaks out and workers can not get away W,P,E,A 4 3 12 Works Supervisor to inform Chief 9(3x3) Superintendent
and get injured. Mechanic and head of Emergency Action
Team (Superintendent) immediately and to
take action accordingly.
Superintendent to inform first aider to Superintendent
stand-by for rescue. & first aider

After receiving the message, the Superintendent

Superintendent immediately appoints
someone to have a vehicle ready in case
there is the need to send casualties to
hospital.
After the fire, the Superintendent shall Superintendent
convene a meeting to review the causes
of the fire and the accident and draw up
precautionary measures to prevent the
same from happening.
Guidelines on Safety of Tower Cranes
35
Appendix B.2
Guidelines on Safety of Tower Cranes

Appendix B.3
Sample Method Statement for Dismantling of Tower Crane

Site Name : _________________________

Project Item : ________________________

Scale: 1:700

Dismantling sequence and weight and length of various parts

Dismantling steps Name of parts Weight Length
1A counter-jib ballast 2.1 tonnes 1940 mm
1B counter-jib ballast 2.1 tonnes 1940 mm
1C counter-jib ballast 3.15 tonnes 2840 mm
1D counter-jib ballast 3.15 tonnes 2840 mm
1E counter-jib ballast 3.15 tonnes 2840 mm
1F counter-jib ballast 3.15 tonnes 2840 mm
2 hook 0.53 tonnes 1710 mm
3 jib + trolley 9.3 tonnes 60000 mm
4G counter-jib block 3.15 tonnes 2130 mm
5 counter jib + hoisting drum 9.2 tonnes 15840 mm
6 A-frame + slewing ring + cabin 7.3 tonnes 4720 mm
7 mast 1.86 tonnes 6000 mm
8 mast 1.86 tonnes 6000 mm
9 mast 1.86 tonnes 6000 mm
10 mast 1.86 tonnes 6000 mm
11 concrete footing

36
 Guidelines on Safety of Tower Cranes
Sample Layout Plan

Tower crane

Distance ? m
Safe working load ? tonnes
Distance ? m
Safe working load ? tonnes
Unloading area

Longest distance ? m
Safe working load ? tonnes

Hydraulic derrick crane

A layout plan should show the following information –

1) distance between hydraulic derrick crane and the centre of tower crane
2) name of hoisting facilities for dismantling a tower crane
3) brand name of hoisting facilities
4) model number of hoisting facilities
5) distance between storage area for hoisting facilities and centre of the tower crane
6) hoisting area of the hoisting facilities
7) radius of the hoisting facilities and their maximum safe working load
8) exclusion zone for the dismantling work
9) storage area for parts of the tower crane
10) storage area for jib and counter-jib
11) if hydraulic derrick crane is used, the condition of the ground for supporting the derrick
crane, way and materials for cushioning
12) weight to be carried by ballast of hydraulic derrick crane

37
Guidelines on Safety of Tower Cranes

Sample Tower Crane Dismantling Procedures

Step 1: Dismantle the counter-jib block

Scale : 1:700

10 m

32.7 m For the purpose

of balance, do
50T not dismantle
Hydraulic this counter-jib 2m
derrick crane ballast

Platform surface
Basement
7m

Works Procedures:
1. Dismantle 1A to 1F counter-jib ballast with a derrick crane!

Important Points Hazard Identification

Distance between the tower crane
Fall of person:
and the derrick crane is 7 m, the safe
1. Technicians must use safety belts
working load is 13 tonnes
Fall of object:
1. Enclose the affected area, no access except for
Reserve one counter-jib ballast for
tower crane dismantling workers
balance when dismantling the jib
2. Hand tools must be tied to the appropriate
position with a rope

38
 Guidelines on Safety of Tower Cranes
Sample Tower Crane Dismantling Procedures

Step 2: Dismantle the hook and retrieve the hoisting wire rope

Works Procedures:

1. Use wires and shackles to secure the hook on the jib.

2. Use the tower crane to coil hoisting wire back to hoisting drum.

Important Points Hazard Identification

Good communication must be Fall of person:
maintained with the tower crane
operator when retrieving the hoisting 1. Technicians working at the jib must use “double
wire rope shackle” safety belts
Fall of object:
Only tower crane operators with a 1. Enclose the affected area, no access except for
certificate will be allowed to operate tower crane dismantling workers
the tower crane
2. Hand tools must be tied to the appropriate
position with a rope

39
Guidelines on Safety of Tower Cranes

Sample Tower Crane Dismantling Procedures

Step 3: Dismantling the jib

Scale : 1:700

7.4 m

32.7 m
50T
Hydraulic 21 m
derrick crane

Control rope Platform surface

7.8 m 4m Basement

Works procedure :
1. Use 4 chain slings of 2.4 m long and 2 wires to hoist the centre of the jib according to
the manual.
2. Tie the trolley properly with rope and retrieve the cable.
3. Hammer out the square-shaped pins and the steel plate which are connected to
A-frame.
4. Afterwards, hammer out the small pins joining the wedge lock and the slewing ring.
5. Slightly hoist up the jib to a 5 degree angle with the ground level and hammer out the
pins of the oval core within the wedge lock.
6. Use the derrick crane to dismantle the whole jib and lay it on the ground before
continuing with the dismantling process.

40
 Guidelines on Safety of Tower Cranes
Important Points Hazard Identification
Distance between the tower crane Fall of person:
and the derrick crane is 7.8 m, the 1. Technicians working at the jib must use “double
safe working load is 12.3 tonnes shackle” safety belts
Fall of object:
Before dismantling the jib, the 1. Enclose the affected area, no access except for
trolley must be tied to the jib with a tower crane dismantling workers
coarse string 2. Hand tools must be tied to the appropriate
position with a rope
Overloading of derrick crane:
Must use a control rope to keep the
1. The derrick crane operator and signaller must
jib within the radius of safe hoisting
ensure the object for hoisting must not exceed
of the derrick crane
the safe working load.
Must use a block to secure the jib
so as to maintain a correct central
position and prevent the release
of too much energy during the
dismantling process
Adequate space must be reserved on
the ground level for placing the jib
of 60 m long

41
Guidelines on Safety of Tower Cranes

Sample Tower Crane Dismantling Procedures

Step 4: Dismantle the last ballast

Scale : 1:700

10 m

32.7 m

50T
21 m
Hydraulic
derrick crane

Platform surface

7m Basement 4m

Works Procedures:
1. Dismantle the 4G ballast with a derrick crane

Important Points Hazard Identification

Distance between the tower crane
Fall of person:
and the derrick crane is 7 m, the safe
1. Technicians must use safety belts
working load is 13 tonnes
Fall of object:
1. Enclose the affected area, no access except for
tower crane dismantling workers
2. Hand tools must be tied to the appropriate
position with a rope

42
 Guidelines on Safety of Tower Cranes
Sample Tower Crane Dismantling Procedures

Step 5: Dismantle the counter jib (with hoisting drum)

Scale : 1:700
11 m
8.8 m

32.7 m

50T 21 m
Hydraulic
derrick crane Control
rope Control
Platform rope
surface
9m Basement 4m

Works Procedures:
1. Use 4 chain slings of 2.4 m long to lift up the centre of the counter jib according to the
manual.
2. Hammer out the small pins joining the wedge lock and the slewing ring.
3. Slightly lift up the counter jib to a 5º angle, hammer out the connecting pins on the
tie bar of the counter jib. Then, hammer out the small pins of the oval core within the
wedge lock.
4. Use the derrick crane to dismantle the whole counter jib and lay it on the ground before
continuing with the dismantling process.

43
Guidelines on Safety of Tower Cranes

Important Points Hazard Identification

Distance between the tower crane
Fall of person:
and the derrick crane is 9 m, the safe
1. Technicians must use safety belts
working load is 11 tonnes
Fall of object:
Must use a control rope to keep the
1. Enclose the affected area, no access except for
dismantled counter jib within the
tower crane dismantling workers
radius of the safe hoisting of the
derrick crane. 2. Hand tools must be tied to the appropriate
position with a rope
Must use a block to secure the
Overloading of derrick crane:
counter jib so as to maintain a correct
1. The derrick crane operator and signaller must
central position and prevent the
ensure the object for hoisting must not exceed
release of too much energy during
the safe working load.
the dismantling process
Adequate space must be reserved for
placing the whole piece of counter
jib

44
 Guidelines on Safety of Tower Cranes
Sample Tower Crane Dismantling Procedures
Step 6: Dismantle the A-frame + slewing ring + cabin

Scale : 1:700
6.8 m

32.7 m

50T
Hydraulic
derrick crane Platform
surface

Basement 4m

6.6 m

Works Procedures:
1. Use 4 chain slings of suitable length to lift up the A-frame + slewing ring+cabin
according to the instruction manual.
2. Loosen the screws connecting the slewing ring and the mast with a hydraulic block.
3. Use a derrick crane to dismantle the A-frame+slewing ring+cabin and lay them on the
ground.

Important Points Hazard Identification

Distance between the tower crane
Fall of person:
and the derrick crane is 6.6 m, the
1. Technicians must use safety belts
safe working load is 13 tonnes
Fall of object:
1. Enclose the affected area, no access except for
tower crane dismantling workers
2. Hand tools must be tied to the appropriate
position with a rope
Derrick crane overloading:
1. The derrick crane operator and signaller must
ensure the object for hoisting must not exceed
the safe working load.

45
Guidelines on Safety of Tower Cranes

Sample Tower Crane Dismantling Procedures

Steps 7 to 10: Dismantle the four masts

Scale : 1:700

10.2 m

32.7 m

50T
Hydraulic
derrick crane Platform
surface

4m Basement

6.6 m

Works Procedures:
1. Use 4 chain slings of suitable length to lift up one mast.
2. Loosen the screws connecting the masts with a hydraulic block.
3. Use a derrick crane to dismantle the masts and lay them down to the ground one by
one.

Important Points Hazard Identification

Distance between the tower crane
Fall of person:
and the derrick crane is 6.6 m, the
1. Technicians must use safety belts
safe working load is 13 tonnes
Fall of object:
1. Enclose the affected area, no access except for
tower crane dismantling workers
2. Hand tools must be tied to the appropriate
position with a rope

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 Guidelines on Safety of Tower Cranes
Sample Tower Crane Dismantling Procedures

Step 11: Dismantle the concrete footing

Works Procedures:
1. Cut away the outcrop of the concrete footing with oxy-acetylene torch.
2. Use a derrick crane to dismantle the cut-off outcrop down on the ground.

Important Points Hazard Identification

Fire/explosion
1. Hot works must be carried out in accordance
Only oxy-acetylene torch operators with the requirements of the hot works safe
with a certificate will be allowed to working procedures.
operate the oxy-acetylene torch 2. Prepare a fire extinguisher
3. Technicians must use appropriate safety personal
protective equipment

End

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Guidelines on Safety of Tower Cranes

Appendix B.4

Sample Appointment Letter of Competent Persons

of Tower Crane Dismantling

To: ABC construction company

Site Name:
Attention: Safety Officer

The following persons are appointed as Competent Persons to supervise the dismantling
of tower crane MD-175 at site xxxx of your company until completion of the works. The
Competent Persons have 10 years’ relevant experience and have worked on tower crane of
the same model line.

Crane Operation Contact

Name Post Green Card Site Position
Certificate Telephone
Competent Up on the
Person tower crane

[Specialist Contractor’s name] Date

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 Guidelines on Safety of Tower Cranes
Sample Appointment Letter of Senior/Junior Workmen

To: ABC construction company

Site Name:
Attention: Safety Officer

The following personnel are appointed as senior/junior workmen for dismantling tower
crane MD-175 at site xxxx of your company until completion of the works.

Name Post Types of Certificate Held and their Serial Numbers

Green Card Crane Certificate of Certificate of Years of
Operation Rigger Safety Gas Safety Relevant
Certificate Operation Training Experience
Senior
Workman
Senior
Workman
Junior
Workman
Junior
Workman

[Specialist Contractor’s name] Date

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Guidelines on Safety of Tower Cranes

Sample Workers Engaged in the Dismantling of Tower Crane

To: ABC construction company

Site Name:
Attention: Safety Officer

The following personnel will attend the works safety meeting before the start of works.

Name Post Types of Certificate Held and their Serial Numbers

Green Card Crane Certificate of Years of Site Position
Operation Rigger Safety Service
Certificate Operation
Senior
Workman
Senior
Workman
Senior
Workman
Junior
Workman

[Specialist Contractor’s name] Date

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 Guidelines on Safety of Tower Cranes
Annex C
Qualification and Experience
of Site Personnel Engaged in Tower Crane Operations

Competent Person

(A) Role

• A competent person supervises the working crew of the operation.

(B) Qualification

• Registered Skilled Worker of the trade “To carry out erection, dismantling,
telescoping/climbing of tower crane, and the hoisting of materials, tools and
equipment related to the aforesaid work” under the Construction Workers
Registration Ordinance (CWRO). (To be implemented in six months after the
trade is available for registration)

(C) Experience

• At least 10 years of relevant experience; and

• Experience in operating tower crane in the same model line, or completion of
familiarization training on the same model line.

(D) Training

• Completion of following courses –

- Safety Training Course For Construction Workers of Specified Trade (Silver
Card Course)–Tower Crane Worker (Erecting, Dismantling, Telescoping &
Climbing) (“EDTC Course”) offered by CICTA; and
- Training for Tower Crane Competent Person (Erecting, Dismantling,
Telescoping & Climbing) offered by CICTA. (To be implemented in six
months after launching of the course)

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Guidelines on Safety of Tower Cranes

• Competent Person in charge of erection or dismantling of a tower crane using

derrick crane should also have completed the Certification Course with Imbedded
Certification Test for Derrick Crane Operator offered by CICTA

(E) Competencies

• A Competent Person should b e able to –

- brief and instruct his crew to execute the operation in accordance with the
method statement;
- draw the attention of his crew to important safety warnings and precautions
stipulated in the manufacturer’s manual, method statement, critical parts
checklist and risk assessment report (in particular the parts marked as
“Danger”, “Cautions” and “Hold Points”);
- response to questions raised by his crew members and provide appropriate
directives to them; and
- conduct visual inspection to ascertain the integrity of key components of the
tower crane prior to commencement of the operation.

Senior workman

(A) Qualification

• Registered Skilled Worker of the trade “To carry out erection, dismantling,
telescoping/climbing of tower crane, and the hoisting of materials, tools and
equipment related to the aforesaid work” under CWRO. (To be implemented in
six months after the trade is available for registration)

(B) Experience

• At least four years of related work experience

(C) Training

• A senior workman should have completed the following courses organized by

CICTA –

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 Guidelines on Safety of Tower Cranes
- Safety Training Course for Construction Workers of Specified Trade (Silver
Card Course) – Construction Materials Rigger (“Rigger Course”); and
- EDTC Course

Junior Workman

(A) Qualification

• Registered General Worker under CWRO

(B) Training

• A junior workman should have completed the following courses organized by

CICTA –
- Rigger Course; and
- EDTC Course

(C) Supervision

• A junior workman with less than four years of experience should work only under
the direct one-to-one supervision of a senior workman.

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Guidelines on Safety of Tower Cranes

Annex D
Summary of Recommended Improvement Measures
Section and
subsection Implementation
Improvement Measures Implementing parties
in main timeframe
text
E Checking before Erection of Tower Crane
(i) Pre-delivery checking Tower crane owners Upon issue of
publication
(ii) Checking of anchorage Tower crane owners Upon issue of
Principal Contractors publication
(iii) Checking of supporting Tower crane owners Upon issue of
structure Principal Contractors publication
F Improvement of site supervision
(i) Appointment of Principal Contractors Upon issue of
supervising engineer publication
(ii) Risk assessment and Principal Contractors Already
method statement Specialist Contractors implemented
(iii) Pre-installation checking Principal contractors Upon issue of
publication
(iv) Pre-operation checking Principal contractors Upon issue of
Specialist Contractors publication
(v) Pre-use verification Principal contractors Already
implemented
G Qualification and Principal contractors Upon issue of
experience of specialist Specialist contractors publication
contractors
H Training and experience Principal contractors Already
of competent persons Specialist contractors implemented1
and workmen

1
Except for (i) Registration as Skilled Worker of the trade “To carry out erection, dismantling, telescoping/climbing of tower crane, and the
hoisting of materials, tools and equipment related to the aforesaid work” under the Construction Workers Registration Ordinance (CWRO); and
(ii) Completion of training for Tower Crane Competent Person (Erecting, Dismantling, Telescoping & Climbing). These will be implemented
in six months after the availabilty of the trade for registration and in six months after launching the course respectively

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