WORK AT HEIGHT
High Incidences of Accidents
while working at Height
Miscellaneous
08%
Transport vehicle
16%
Electrocution
11%
Fall of Object
Fall of Person
08% 57 %
Falls in Construction
Falls are the leading cause of deaths in the
construction industry.
Most fatalities occur when employees fall from open-
sided floors and through floor openings.
Falls from as little as 4 to 6 feet can cause serious
lost-time accidents and sometimes death.
Unguarded open-sided floors, periphery and
platforms 6 feet or more in height led to many
accidents.
Working at Height
We shall discuss about;
Preventing fall of materials & person while
working in
Ladders
Scaffolds
Working Platform
Working on Roofs
Safety Equipment & Devices
LADDERS
LADDER
TYPES
PORTABLE
STOCK (SINGLE)
EXTENSION
STEP
TRESTLE
ROPE
BUILT-UP / FIXED
LADDERS
Construction:
The design of ladder shall confirm to
IS 3696 (Part 2): 1991
Metal ladder shall conform to IS 1977:1975
Aluminium alloy shall conform to IS 617:1975
Side rails (Stiles) of metal ladders shall be of sufficient
cross-section to prevent excessive deflection in use.
Slip-resistant shoes shall be used to avoid danger of
slipping.
Make shift ladders shall not be permitted.
PORTABLE LADDER
Single / Stock Ladder
(IS 3696 – 1966)
Single section only,
Length not more than 10 m,
Side rails may be parallel or
wider at bottom.
Distance between rungs.
Not less than 250 mm.
Not more than 350 mm.
Must support 4 times the
maximum load.
Width between side rails;
290 mm - up to 3 m Length
+6 mm - for every 0.3m
Length
Extension Ladder
Over-all length not to exceed 18 m;
Sliding section not to exceed two in
number.
Step Ladder
A- shaped, Self-supporting, hinged at upper
end with a spreader arrangement
Wide flat step at one end only & other acts
as a strut.
Overall height not more than 6 m &
chained / Roped mid-way & bottom is ht
more than 3 m;.
Do not use the top platform of the
stepladder unless designed.
Min. width 30 cm at top with a spread of
25 mm for every 30 cm length.
Trestle Ladder
Similar to step ladder, but the other side also
used for climbing and rungs circular in shape.
Height not to exceed 6m;
The rungs not less than 30 mm
dia;
Rungs spaced not more than 45
cm
15 cm per 30 cm Min. width 30
cm at top with a spread of 25 mm
for every 30 cm length.
Built-up/Fixed Ladder
These are built and fastened to the job & not
moved
Rung spacing 300 mm c/c max;
When height exceeds 9m, landing
platform to be provided;.
Cage or well, and multiple ladder
sections, each section not exceeding 50
feet;
Distance between the inner face of the
fixed ladder:
290 mm for 3 m & 6 mm increase
for every 0.3 m increase in length.
Ladders
DO's
Angle should be approximately 750 to the
horizontal (1:4) four up, one down
Stiles to extend at least 1 m above the
step-off point
No rung should be missing
Laced at the level of the platform
Firm & fitted with a non-slippery foothold
Ladders
DO's
Rungs shall be clear of oil/ grease etc.,
Secure the top of the ladder, as needed.
In aisles or where there may be the danger
of traffic, have someone hold the ladder.
Post a warning sign..
Face the ladder when ascending or
descending.
Hoist materials or attach them to a belt.
Ladders
Don'ts
Hang any tool from the rungs
Stand any higher than the third rung from the
top of a ladder.
Keep metal and wet wooden ladders near live
electrical circuits.
Use ladder horizontally as a work platform.
Stretch or reach beyond the side rails of a
ladder. You could lose your balance.
Ladders
Don’ts
Use make-shift ladders.
Allow more than one person at a time.
Face away from the ladder while ascending or
descending.
Carry a load that will prevent both hands from
holding rung.
Over-reach on a ladder.
Scaffold Safety
Pole/ Post/Standard
Runner/
Ledger
Bearer
Sole Plate
Base Plate Cross Bracing
Longitudinal Bracing
Independent Scaffold
Pole/Post/Standard
Bearer
Runner / Ledger
Cross Bracing
Sole Plate
Base Plate
Scaffolding
A temporary structure that supports one
or more platforms;
Support workmen, plant and materials
during:
Construction
Maintenance
Repairs &
Demolition
Types of Scaffold
3 basic types:
Supported scaffolds:
Platforms supported by rigid, load
bearing members, such as
Standards, legs, frames, &
outriggers etc.,
Suspended scaffolds: Platforms
suspended by ropes or other non-
rigid, overhead support
Aerial Lifts -- such as “Boom
trucks”
Scaffold Specification
(OSHA)
Medium Heavy
Light Duty Duty Duty
25 psf 50 psf 75 psf
Uniformly Distributed Load
122kg/m2 244kg/m2 366kg/m2
Transverse distance between Posts
1.8m 1.8m 1.8m
Longitudinal Distance between Posts
3.m 2.4m 1.98m
Vertical distance between Runners
(Ledgers) 1.8m 1.8m 1.8m
Cross or Transverse Bracing
Cross bracing shall be
installed across the width
of the scaffold at every
third set of Poles and Pole/Post/
every forth Runner Standard
Bearer
vertically. Runner/
Ledger
Such bracing shall extend
Cross
diagonally from the inner Bracing
and outer runners upward Sole Plate
to the next outer and
inner Runners
Base plate
Longitudinal Bracing
Longitudinal diagonal bracing on the
inner and outer rows of poles shall be
installed at approximately a 450 angle Pole/Pos
from near the base of the first outer post Standard
Bearer
upward to the extreme top of the
Runner/
scaffold. Where the longitudinal length of Ledger
the scaffold permits such bracing shall Cross
Bracing
be duplicated beginning at every Fifth
Sole Plat
Post.
In a similar manner longitudinal
Base plate
diagonal bracing shall also be installed
from the last post extending back and
upward toward first post.
Tying to Structure
(OSHA)
Tied Post
Tied Post
The entire scaffold shall be tied securely against the building at
intervals not exceed 30 feet horizontally and 26 feet vertically.
Plan Bracing
(IS 3696 (Part 1) 1987)
In places, where tying to structure is not possible Plan Bracing can be provided
as shown
Tying to Structure
Tie through Opening Scaffold fixed to Form ties
Cross or Transverse Bracing
Tie around a Column
Tubular Frame Scaffold
(OSHA)
Designed to support 4 times the maximum rated
load.
Braced by cross bracing or diagonal braces or both.
Set on adjustable bases or plain bases.
If load bearing capacity of soil less base to be set on
sole plate.
Each such joint to have a coupler two stacking pins
Secured to the structure at Intervals not to exceed
9m (30 feet) horizontally and 8m (26 feet) vertically.
Scaffolds above 38m (125 feet) height shall be
designed by a Professional Engineer
Mobile Scaffold
Mobile Scaffold
When free-standing height not exceed four times
the minimum base dimension.
To support four times the maximum intended
load.
All wheels shall be provided with a positive
locking device
To be braced by cross bracing or diagonal braces
or both
Platforms shall be tightly decked secured against
displacement.
Platforms shall be provided with guard rail
Mobile Scaffold
The force to move the scaffold to be applied as
close to the base as practicable
To be moved only on level floors free from
obstructions and openings.
The wheels to be provided with rubber or similar
resilient tires
Workmen not to be allowed to ride on mobile
scaffold.
All materials to be removed before mobile scaffold
is moved.
Wheels to be locked while scaffold in use.
L&T System Scaffolding
L&T System Scaffolding
L&T System Scaffolding
Erection Sequence
After compacting & leveling
the ground, mark the longer
& shorter span dimension of
2.250 m & 1.525 m using
measuring tape.
Place the foot plate at
marked position
Erection Sequence
Assemble the tower spindle with foot
plate using spring locked pin
Place the tower spindle with foot
plate using spring locked pin at all the
four legs of tower
Erection Sequence
Erect the basic frame Erect the basic frame 1.80
1.80 at other end
Erection sequence
Place the bracing H-225
between the Basic frame
Place the Diagonal bracing
D-18.225 at the same
direction
Erection Sequence
Place the horizontal
bracing H-225 between
the basic frame at upper
level
Follow the Same
Sequence of Placing of
the Bracings at other end
Erection Sequence
Place the plan bracing
D-12.225 to check the
diagonal of tower at top
level
Check the level of Tower
using water level
Erection Sequence
Align the tower using line
thread
Place 3 no’s of Scaffold
board top of tower
Erection Sequence
Tie the safety belt at top
of the basic frame
Insert the HD coupler
top of the basic frame
using spring locked pin
Erection Sequence
Insert the HD coupler top of the
basic frame using spring locked
pin all the four legs
Erect the second unit of basic
frame 1.20
Erection Sequence
Erect the basic frame 1.20 at
other end and insert the
spring locked pin at 4 legs
Place the diagonal bracing
D-12.225 and Horizontal
bracing H-225 between the
basic frame 1.20
Erection Sequence
Repeat the said
procedures.
View of the tower after
Erection
Foundation Formwork
Care to be taken while
lowering the components into
the excavated pit
Formwork components to be
stacked at a Safe distance to
prevent falling of the
components and sand slide
into the excavated pit
Wall / Column formwork
• Good Rigging Practices to be
followed while lifting the formwork
assembly
• Strength and Location of lifting
hooks on the formwork to be
checked
• Panels to be pre-checked for
defects or damages before lifting
• No loose materials to be kept on the
formwork panels or platforms while
lifting the panel
Flex System
All the main props to be fitted
with Tripod
All the intermediate props to
be fitted with supporting head
In ground level work, proper
earth compaction and
necessary bearing below the
prop shall be given
Heavy Duty Tower
• Every 6m interval (vertically)
bracing to be fixed with
permanent structure or from
one tower to the other.
• Ground level earth to be
compacted well for better
loading
Stair Tower
Ground level earth to be
compacted well
Every 6m interval (vertically)
bracing to be fixed with
permanent structure
Coir rope / binding wire not to be
used in place of M10 bolt
Bracings & lock pins not to be
omitted under any circumstance
Access Scaffold
Ground level earth to be
compacted.
The system to be braced at
every 6m-height level with the
permanent structure.
Old / damaged components not
to be used.
Coir rope / binding wire not to be
used in place of Platform hanger
Bracings not to be omitted under
any circumstance.
Lift Shaft Formwork
Proper Slinging and Rigging Practices to be
followed while lifting the formwork assembly
Strength and Location of lifting hooks on the
formwork to be checked
No loose materials to be kept on the formwork
panels or platforms.
Panels to be pre-checked for defects/damages
before lifting
Adequate space (gap) to be ensured before lifting
the inner panel platform
Slipform
Provision for Earthing and Bracing of access tower at
RCCBs of 30mA sensitivity every 6m height
for electric power supply Handrail and toe board in
Lightning arrester the platform
Aviation Light Safety nets to trap the
falling materials
Communication
arrangement Adequate illumination
Safety aspects in Hoist Fire Extinguishers
and Winch Workmen entry register
Stacking of Materials
Collect & stack required components &
tools nearby work place
Scaffolding
Hazards / Risks
Failure to secure the scaffold to the
building;
Inadequate bracing;
Failure to brace it adequately;
Inadequately supported scaffold board;
Erected on uneven ground;
Use of unsuitable or faulty materials;
Absence of suitable number of couplers;
Inadequate access or unsecured ladder;
Hazards / Risks
Inadequate or irregular platform width;
Overloading of platform and scaffold;
Use of makeshift materials;
Gang ways obstructed.
Absence of toe boards and guard rails where
necessary;
Absence of good drainage system near the standards
to prevent erosion.
Precautions to Be Taken
Surface - firm, level and compacted;
Sole plates below the base plates;
Sole plate shall rest on at least two vertical pipes
and should extend 600 mm beyond the vertical
pipes;
Staging braced at every height of 6 m;
Sufficient diagonal bracing.
Scaffolding
Erection
Scaffolding
Erection
By skilled workmen with the supervision of a
competent Supervisor.
Cordoning the area.
Lifting of frame and other parts by the use of
Derrick & Pulley arrangement
Ladder shall be used for climbing up and down.
Red Tag shall be provided to caution that the
scaffold is under erection
Scaffolding
Erection
At the end of the day, if a scaffold is going to be left
half-erected, it is essential to lower all the loose
scaffold materials down and ensure that the scaffold
is braced adequately to the building/structure.
Double Lanyard Safety Harness shall be used by all
workmen engaged in scaffold erection works.
Dismantling of Scaffolding
Dismantling only by Skilled Workmen
Cordoning of the area
Red Tag to be displayed
Lowering of the materials by the use of Derrick and
Pulley arrangement
Each tier shall be completely dismantled and the
material lowered to the ground before beginning to
dismantle the next tier
Materials not to be dropped
Dismantling of Scaffolding
Double lanyard safety harness to be anchored to a
strong structure or lifeline before attempting to
loosen stuck or jammed parts
At the end of the day, if a scaffold is going to be left
half-dismantled, it is essential to lower all the loose
scaffold materials down and ensure that the
scaffold is braced adequately to the
building/structure
All the dismantled materials shall be stacked in the
appropriate manner at the designated place
Scaffold Tag System
Date of Inspection:
Signature of Competent Person
Date of Inspection :
Signature of Competent Person
Scaffold Tag System
Red Tag
This tag indicates that the scaffold is under
erection or dismantling or has not been
inspected or is not safe for use (by anyone
other than scaffold gang).
Green Scaffold Tag
This tag indicates that the scaffold is
complete & it has been inspected by
competent person and is safe for use.
GREEN scaffold tag is valid for one week
from the date of last inspection.
WORKING PLATFORM
Work-Platform
Working Platform
Designed to support the weight of the personnel and
equipment to be used.
Fully decked with scaffold boards.
Scaffold boards to be secured against
displacement.
Erected on stable scaffold.
Provided with a ladder or any other safe means of
access.
Provided with guardrail:
Height of the top rail between 900 mm to 1200
mm.
Toe guard to be of minimum 100mm height.
Working Platform
Midrail to be provided halfway between the
platform and the top rail
Toe guard shall be of minimum 100mm height
Posts and rails shall be capable of withstanding a
force of at least 900N applied at any point, or
withstanding any load likely to be applied
Barriers to be provided on open edges, holes and
openings in the platform.
The minimum width of Working Platform shall be
as follows,
Only Workmen: 600 mm
Men, tools & materials: 900 mm
Men, tools, material & wheel barrows: 1200 mm
Scaffold Board
Few Don’ts
Crane Suspended Platform
Crane Suspended Platform
Man-cage to be limited unless there is no safer means of
access to an elevated work area.
Use of Crane Suspended Platform for carrying out welding
works shall be avoided, as this may lead to damage of
crane hoist rope.
Not to be loaded above 50% of the lifting capacity
Have a minimum safety factor of ten for the load line (wire
rope) of the crane.
Crane Suspended Platform
To be designed by a Structural Design Engineer. The man
cage shall be designed so as to:
Support self weight and at least 5 times the maximum
intended load.
Keep tools, materials, and equipment from falling by
having a standard guardrail system that is enclosed
from the toe board to the mid-rail.
Have rotation-resistant rope with a minimum safety
factor of ten.
Keep the platform free from sharp edges, which may
cause laceration to the occupants
Adequate headroom for workmen
Crane Suspended Platform
Hitch:
Provided with four leg bridle hitch connected
to a master link or shackle so that the load is
evenly positioned among the bridle legs
Hooks must provided with Hook Latch.
“Mousing” is prohibited.
The designated slings not to be used for any
other purpose than hoisting personnel.
Crane Suspended Platform
Use:
Training to those, who will travel
Safety belt hooked to the crane hook
Tagline to control the movement
Unguarded Edge
Unprotected sides and edges must have guardrails or
equivalent
Sides & Edges - Improper protection
This 1/4" nylon rope alone is not a proper way
to guard this open floor
Floor Openings
This opening could be made safe by using a
guardrail, or strong cover
Improperly covered Floor Openings
• Cover completely and securely
• If no cover, can guard with a guardrail
Few Don’ts
Few Don’ts
Few Don’ts
Few Do’s
Few Do’s
Fall Protection
Safety Belt
Lanyard Anchorage
Point
Full Body harness / Max Free
Waist Safety Belt Fall Allowed
1.8 m
For more than 2.0 m height
Lanyard to be anchored to a fixed
point
2 m or
Free-fall not to exceed 1.20 m more
Lanyard not more than 2 m.
Ground Level or Level
of adjacent surface
Full Body Safety Harness
(IS 3521 :1999)
Working near floor Edge & Opening
Rope Grab Fall Arrester
Ladder
Rope
Grab Fall
Arrestor
Full Body
Harness
Vertical
Class -L Life Line
Rope grab fall arrestors used during vertical
movement such as ascending or
descending Scaffold towers, vertical ladders
etc.
Rope Grab Fall Arrester
Rope grab fall arrestors used to protect fall
of workers during vertical movement such
as ascending or descending Scaffold
towers, vertical ladders etc.
Life Line
20mm diameter polypropylene rope or 8 mm wire
rope
Anchorage capable of supporting at least 2264 kgf
Anchored to strong points
The sag of the life line shall not be more than 15
degree Life Line
Anchorage
Point
Lanyard Support
Full Body harness /
Waist Safety Belt
Usage of lifeline
Retractable Type Fall Arrester
Retractable Fall Arrester
Retractable fall arrestors shall be
used in places where high risk of fall
of workmen persists.
This fall arrestor can be directly
anchored to the anchorage or can be
used in conjunction with a lifeline
Safety Net
Safety net protects
Person from falling
Protect person working below
Safety net distance should not exceed 7.5 m
Net shall extend
up to 1.5 m 2.40 m
1.5 to 3.0 m 3.00 m
> 3.0 m 4.00 m
Person from falling
Tie cord at every 1 m
Border rope to withstand 5000 lbs (2268kg)
Drop test - 180 kg from 1 m above the working
area
Boatswain Chair
Suspension Anchorage
Suspension rope
Fall Arrest
Anchorage Point
Rope Grab Fall
Arrestor with
vertical lifeline
Full body harness with
Suspension seating
arrangement
Boatswain Chair
Suspension Anchorage
It must be capable of supporting at least twice the
potential impact load of a worker's fall
Suspension seating arrangement
Seating arrangement with strap & front suspension
O-ring
Boatswain Chair
Suspension Rope
Rope with a locking snap-hook.
Not less than 36 mm polypropylene rope or
Any synthetic rope of equivalent strength
For hot works steel wire rope of minimum
10mm diameter shall be used
Fall Arrest Anchorage Point
Anchorage capable of supporting at least
2264 kgf
Boatswain Chair
Testing
Tested at least once a fortnight by a
competent person
Testing to be done by raising the working
platform 300 mm above the ground
loading it with at least 3 times the
maximum weight intended load
