Fire & Explosion:
1. Pool Fire
Pool Fire → A pool of burning liquid.
Definition: A fire involving a flammable liquid that forms a pool on a flat surface or open container.
Example: A gasoline spill on the floor catches fire.
Characteristics:
Flames are flat and spread following the spill area.
Liquid fuel source, usually hydrocarbon.
Risk: High heat radiation, can ignite the surrounding area.
2. Jet Fire
Jet Fire → The release of pressurized gas/liquid that burns torch-like.
Definition: A fire caused by the release of high-pressure gas or liquid that ignites immediately after release.
Example: A leak in a pressurized gas pipe (LPG, LNG, H₂).
Characteristics:
The flame forms a long, torch-like flame.
It is directed in the direction of the fluid jet.
Risk: Flame impingement (fire directly impacting a structure → can cause material failure).
3. Flash Fire
Flash Fire → A gas/vapor cloud burns rapidly without overpressure.
Definition: The rapid ignition of a flammable gas/vapor cloud after mixing with air at a flammable concentration.
Example: A gasoline vapor cloud ignites without a major explosion.
Characteristics:
Occurs very quickly (only a few seconds).
Does not produce significant overpressure.
Risk: Brief but extensive heat exposure (burns skin and clothing).
4. Fireball
Fireball → A large, short-lived fireball.
Definition: A large fireball resulting from the rapid release of flammable gas/liquid and subsequent combustion in air.
Example: A burning LPG tank explodes, forming a fireball.
Characteristics:
A giant fireball in the air.
Short duration (seconds to minutes).
Risk: High heat radiation, can be fatal within a certain radius.
5. BLEVE Fire (Boiling Liquid Expanding Vapor Explosion)
BLEVE → Explosion of a pressurized liquid vessel → fireball.
Definition: An explosion caused by the rupture of a pressurized vessel containing a boiling liquid, which then ignites.
Example: An LPG tank explodes → a large fireball.
Characteristics:
A combination of a physical explosion and fire.
Often produces a fireball.
Risks: High pressure and heat, massive damage.
6. Dust Fire / Dust Explosion
Dust Fire/Explosion → burning/exploding dust.
Definition: A fire or explosion caused by flammable solid particles suspended in the air.
Examples: Coal dust, flour, aluminum powder.
Characteristics:
Occurs when dust is suspended in the air at a certain concentration.
Risks: Often causes secondary explosions in industrial facilities.
7. Flashover & Backdraft (specifically in enclosed buildings)
Flashover/Backdraft → typical of enclosed space fires.
Flashover: All materials in the space ignite almost simultaneously due to accumulated heat.
Backdraft: A fire explosion caused by the sudden introduction of oxygen into a closed space containing burning gas.
9.1.2.7 WORK AUTHORISATION (PERMIT TO WORK)
ReplyDeleteGreenko has ensured that all the Routine activities are routed through Standard Operating Procedures, whereas all the Non-routine activities are routed through Permit to Work System.
PURPOSE
To establish a procedure for the implementation of Work Permit System.
SCOPE
This procedure applies within the plant premises for carrying out any one or combination of the following works.
• Basic Work Permit.
• Hot work.
• Cold work.
• Electrical /Mechanical Isolation
• Confined Space entry work.
• Excavation work.
• Blasting Permit
• Work at heights.
• Work in /on/around water body
• Lifting & Rigging work.
• Working in the Vicinity of HV lines/Transformers
• Working on Live Electricity.
Title
Basic Work Permit
Hot Work Permit
Cold Work Permit
Electrical / Mechanical Isolation Permit
Confined Space Entry Permit
Excavation Work Permit
Blasting Work Permit
Work at Height Permit
Work Permit for working in, on or around water body
Rigging work Permit
Tool box talk register
DEFINITIONS
ReplyDeleteBasic work permit
This is the basic work permit for any work, while taking this permit if any other permit requirement needs to be fulfilled in such a case all such permits are to be taken along with this permit. If other permit is not required, this permit alone is sufficient as per SOP/Risk Assessment.
Hot Work
Any work procedure, which involves fire and ignition such as welding, cutting, grinding or heating with open flame. Also applicable for work areas where there is possibility of combustible / explosive gas / material leakage are present.
Cold Work
Any work procedure, which involves dismantling / assembling of the equipment, painting, insulation, civil work like flooring etc.
Electrical /Mechanical Isolation
Isolation of any prime mover driven by Electrical /Mechanical Power such as motors, lights and solenoid operated valves, Pressurized valves etc.
Work at Confined Space
Work at any enclosed area, which has the following characteristics:
• Limited means of entry or exit
• Structure that is not designed for extended Human Occupation
• Atmosphere that is actually or Potentially Hazardous
• Potential for Other Hazards
Excavation work
ReplyDeleteAny man-made cut, cavity, trench or depression in an earth surface formed by earth removal below Six inches (i.e., for any cut in earth > 6")
Blasting Work
Any rock/concrete blasting works using explosives.
Work at height
All the jobs where work is carried at heights above 2.0 meters from the floor level or there is a likely hood of fall about more than 2.0 meters.
Rigging Work
Any work involves lifting of the loads by any Lifting Equipment / Vehicle
Vehicle and Road Traffic work
• Any work involves at/near heavy vehicle movement area or works at road side (inside or outside the Greenko Premises).
• Vehicle entry (small /large) to restricted areas.
Permit issuer (issuing authority)
Shift/ Site - Engineer / Shift/ Site in-charge of the Plant / Unit, or any other Authorized Person, who is responsible for issuing the permit.
Permit receiver (receiving authority)
Area Engineer or Shift in- charge or the technician, who is responsible for carrying out the work.
PROCEDURE
ReplyDeleteGeneral requirements of Work Permit System
• Each section / unit control room will have one work permit book at all times.
• The above books will be issued by HRD, from the stationery and HRD will maintain the details of issue of the permit books. The HRD will organize printing of such books with a serial number control.
• The permit forms are made in Triplicate. The original in white and the copies in Yellow & pink. The issuing authority will make the permit in Triplicate, and issue the original (White) to the receiver, retain the copy (Yellow) & send the other (Pink) permit at site. After the completion of work the permit will be sent to MIS department for recording.
• All permits must be issued only from the respective control rooms by the permit issuer or the issuing authority to the receiving authority or receiver.
• HIRA shall be conducted and its recommendations to be implemented and it shall be considered for issuing the Permit. HIRA document shall be attached the permit copy provided to the receiver.
• Before starting the work, a tool box talk needs to be conducted where SOP & Risk Assessment should be briefed. The OHS in charge/ HR in charge / work in charge / workers in charge will discuss the safety aspects of work with the workers involved. Workers will be asked to repeat the safety instructions loudly. An attendance of the workers will be taken in the tool box talk register.
• On completion of the job, the receiver will revert to the issuer with the permit. The permit receiver will make necessary entries in the permit copies (Yellow, White & Pink) and puts his signature at the JOB COMPLETED & EQUIPMENT HANDED OVER column, tick marking it. The permit issuer shall then fill any necessary entries and file the same in the control room for record. Both issuing authority and the receiving authority are responsible for proper documentation and operation of the permit.
• If more than one agency is working on the same job, either of similar or dissimilar in nature, each agency should obtain separate permit. Cross-reference can be made to know how many permits have been issued on the same job. This cross-reference can be written at the bottom of the permit.The in charge of the team / supervisor carrying out the job or any one of the persons working on the job shall always carry the permit form with him.
• The permit receiving authority shall ensure that the contents of the permit and safety instructions are adhered to and shall ensure that the job is performed with strict compliance of safety.
• After completion of the job, the issuer physically checks the completion of all the jobs and ensures that all the permits issued on the equipment are returned and then only takes the equipment in line, after removing the locks, tags etc.,
Extension of the validity of the permit
ReplyDelete• The permit is valid up to completion of work or completion of one shift whichever is earlier. After every shift, extension shall be taken.
• Permit requester shall approach Permit Issuer for extension of existing permit on completion of the specified permit valid time. Permit issuer shall re-verify the site condition and shall further extend the permit for 8 hours.
• The concerned issuing authority shall issue a fresh permit after four times extensions or at the start of the day after Off days or holidays in between or at the fresh start of the work after stoppage due to any other reason such as ‘cancellation of permit’.
Cancellation of permit
ReplyDeleteIf an Emergency is declared after the issue of the Permit, the Permit becomes void.
HOT WORK
i. Equipment Isolated: Ensure whether the equipment is completely isolated by all means. Note: Electrical Isolation Permit is to be filled if the equipment requires Electrical Isolation.
ii. System Depressurized: In case of a Pressure Vessel ensure that the particular equipment where hot work is being carried is fully depressurized.
iii. Fire safety devices are made available: Ensure whether the necessary and relevant portable fire extinguishers (Class - A / B / C / D as per the required class of Fire) are provided nearby. Fire Water Hoses from the Hydrant or running water hoses are kept nearby as per the requirement.
iv. Area cleaned and protected from fire: Ensure that the area where the work is being carried out is cleaned from unwanted and any material which is likely to catch fire while carrying out hot work and which cannot be removed from the area such as cables etc., are to be protected from catching fire by covering them with fire proof material such as asbestos cloth, sheeting etc., or if it can be wet with water it is to be done so.
v. All flammable materials cleared up from work area: Ensure that, all the material that can catch fire while doing the hot work and which can be removed from site has been removed.
vi. Gas Cylinder and Hose in good condition: Ensure that the Gas Cylinders and the Running Hoses or tubing from cylinder to the Torch is in good condition. (The gas cylinders should have neck guards, Cylinder Pressure Gauges in Condition, no leakage of Gasses especially for Acetylene. Non-return valves are provided at the torch to avoid backfire. The tubing is not damaged or ruptured). The cylinders are to be kept upright and oxygen cylinder is to be tied with chain or rope so as to avoid fall of the cylinder.
vii. Welding Machine – Body Earthling, Isolator with Fuses & RCCB Provided: Ensure that the body of the Welding Machine is grounded. For the Welding Machine Isolator trip switch / Fuses are provided, which shall trip or blow of the fuses in case of excessive current. It must be ensured welding activity are to be done in dry condition, Welders are using leather Hand Gloves, Safety Shoes, Welding Holders are Insulated.
ELECTRICAL / Mechanical ISOLATION (Lock-out Tag-out)
ReplyDeleteTick mark the appropriate box, if that particular job has been accomplished
i. Equipment isolated: As the electrical isolation of equipment can be closely linked with its process/ mechanical isolations, ensure whether the equipment is completely isolated.
ii. Breaker switched off: Ensure that the power supply mains breaker at the MCC for the particular equipment where the work is accomplished is SWITCHED OFF. Ensure this, by testing to start the equipment from the field switch. If the equipment doesn't start the right breaker has been isolated, if the equipment starts, it is evident that the right breaker was not switched off. Hence repeat the operation and retest, at the field.
Note: In case of Mechanical Isolation, the inlet and exhaust / outlet valves of the prime mover are to be kept closed, chained, and locked.
iii. Lock no: Ensure that the SWITCHED OFF breaker is locked up, so that it cannot be switched ON, by human error and then enter the particular lock's number in this column.
iv. Tag provided: Ensure that the tags, according to the nature of job, [Operations (Yellow), Mechanical (Gray), & Electrical (Red)] are displayed at the breaker. The departments, who are all working on the particular equipment, shall display their tags.
v. Fuses removed: Ensure that the fuses in the breaker have been removed, if it so necessitates.
vi. MCC / PCC - mains normal supply breaker isolated at substation: Ensure that the motor control centre / Power Control Centre breaker is isolated at the substation, in case the power supply for the particular equipment. Is from substation.
vii. Alternate power supply breaker isolated from other plant: Ensure that the power supply breaker, which supplies the alternate power from the other plant to the MCC panel, is SWITCHED OFF. This is a special case, where, in the particular column is to be filled, when the electrical personnel are carrying out maintenance job on the MCC panels. Also Note: For carrying out the job of electrical maintenance on the MCC panel, the electrical department shall take permit from the section in charge of the plant concerned. And if any lock on the breakers is to be removed as per the requirement of the electrical personnel for carrying out their job, the same has to be mentioned clearly in the permit in the lock & tag column. If the breaker is removed out from the panel, electrical personnel shall ensure that the live incoming bus bars are properly protected by closing the front access door on the MCC panel and shall put a tag on it.
viii. Mechanical Isolation
• Isolate hydraulic, pneumatic and process powered machinery by closing the appropriate isolation valves. Prevent any possibility of machinery movement by disconnecting the power fluid supply and return pipes, or otherwise making safe.
• Isolate engine-driven machinery by shutting off the engine fuel supply and then isolating all the starting systems.
A procedure shall be established, which shall clearly and specifically outline the scope, purpose, authorization, rules and techniques to be utilized for the Electrical Lockout / Tagout, and the means to enforce compliance including, but not limited to, the following:
ReplyDelete• A specific statement of the intended use of the procedure for identifying the equipment / machines to which it is applicable.
• Specific procedural steps for shutting down, isolating, blocking and securing machines or equipment to control Electrical energy.
• Method and person responsible to ensure that all energy sources remain under control when the work extends beyond one shift.
• The procedure shall establish measures to be taken to enforce the procedure requirements.
• The procedure shall require both locks and tags where it is possible to install a lockout device. Tagout alone should not be used.
• Copies of Electrical Lockout / tagout procedures shall be accessible to the Maintenance, Plant Operations and any other employee, who are required to work on electrically operated equipment.
WORK AT HEIGHTS
i. Scaffolding is provided: Ensure that required and appropriate scaffolding was provided for carrying out the job. Refer IS 3696 Part 1 for Safety Code for Scaffolds.
ii. Anchorage for safety belt: Ensure that proper anchorage (For tying the lifeline of the safety belt at a proper place, where it does not crumble out and result in the fall of person. The minimum breaking strength for anchor point must be 22.2 kN as per OSHA 1910.140.
Refer IS 3521 for Industrial Safety Belts and Harnesses – Specification.
iii. Roof ladder is provided: Ensure that the roof ladder is provided for accomplishing the task if it is required. This is needed, especially when the job is being carried out on rooftops, where, asbestos sheeting is provided as rooftop.
Refer IS 3696 Part 2 for Safety Code for Ladders.
iv. Safety belt used is PVC / rubber for electrical use / canvas: Ensure the type of work and where it is carried out and the safety belt supplied / used should be well suited for the accomplishing work.
v. Safety net fixed: Ensure that the safety net has been fixed where ever it is required.
Refer IS 11057 Industrial Safety Nets – Specification.
vi. Area barricaded: Ensure that the area is barricaded such that, persons are not allowed to move underneath displaying the caution, such as "BE AWARE THAT OVER HEAD WORK UNDER PROGRESS AND FALL OF MATERIAL IS LIKELY".
WORKING IN CONFINED SPACES
When entry into a confined space is required, GAS TESTING FOR FLAMMABLE VAPORS AND OXYGEN DEFICIENCY SHALL BE PERFORMED. The order in which gas test to be conducted is Oxygen, Combustible gas and toxic gases. The oxygen limit should be between 19.5 % to 23.5%, No flammable gases present and toxic gases present.
Gas test for % limit to be indicated: Ensure that the gas test has been carried out in the confined space and the result % of gas level as obtained from the test is to be filled in the dash and then tick mark the appropriate column. While carrying out the test, ensure that any existing pocketed areas inside the equipment / area are covered.
Safety Watch / Confined Space Entry Attendant shall be available at all the time during the activity. He shall be well trained & shall be aware of his roles and responsibilities as for Entry Attendant.
Permit issuer
ReplyDelete• Work permit shall provide space for mentioning name, Issuer Certificate number and signature of the Issuer of the work permit. The responsibilities include:
o The Issuer of the Work Permit shall be a Greenko employee who is responsible for the area where the Work permit is requested.
o The Issuer of the Work permit shall be trained and certified through a system that is approved by Safety Section and authorized by the concerned Production / Operations Department head to issue Work Permit within his own area of responsibilities.
o The designated Issuer of Work permit for each area and each type of Work permit shall be identified and communicated to all concerned.
o In case the approved Issuer must leave his shift for any valid reason then other trained, certified and authorized issuer shall be appointed to carry out the responsibilities in the remaining part of the shift.
o The Issuer of the Work Permit shall ensure that:
The Work Permit form is accurately filled.
The equipment and area are prepared and it is safe to perform the work.
Valves are closed, blinds / blanks are installed, lines are disconnected and vent / drains are opened, if required for the assigned work.
The hazards associated with the assigned tasks, including lock-out and tag-out requirements, and process equipment and process condition changes, such as nearby vents, etc., have been identified, and appropriate actions, including communication, taken for the Safety of the personnel who will carry out the assigned task.
Site visit (where the work is to be performed) is carried out along with the Receiver of the Work permit for a joint inspection of the area and equipment, before the Work permit is issued, to assure that the conditions and precautions are satisfactory for the work to proceed.
The Receiver understands the requirements, Personal Protective Equipment to be used and other precautions given in the Work permit and any unusual conditions related to the job, prior to issuance of the work permit.
Work permits are closed with job completed sign before re-starting the equipment on which the work was performed.
o The Issuer of the work permit shall inform the concerned Supervisor(s) of all other area(s) / department(s) that may be affected by the work and obtain their initial(s) on the work permit, as a token of their understanding of the affects to their area.
o The Issuer of the Work permit shall assign a person from his department to closely monitor the condition and the work. The person shall be responsible to stop the work, if the condition warrants it.
o The Issuer of the Work permit shall convey pertinent information about the issued work permits to his reliever.
Permit receiver
ReplyDelete• Work permit shall provide space for mentioning Name or Certificate number and signature of the Receiver of the work permit. The responsibilities include:
o The Receiver of the Work Permit shall be a Greenko maintenance person of the maximum possible extent. The contractors shall not be a receiver. The receiver shall be a trained and certified person jointly by safety section and authorized by respective Head of Department.
o The Receiver of the Work Permit shall ensure that:
The Issuer understands what, where and how work is to be performed.
All the requirements and precautions stated in the Work Permit are complied with.
Electrical, steam, pneumatic and/or any other type of lock-out / tag-out, if required, is performed.
Appropriate tools are used.
Any change in the condition or any abnormality observed is communicated to the Issuer.
Housekeeping is carried out on completion of the job and the work permit is returned to the Issuer after completion of the job or if it is to be continued in the next shift or later on.
o In case the approved Receiver has to leave his shift for any valid reason then other trained, certified and authorized Receiver shall be appointed to carry out the responsibilities in the remaining part of the shift.
o After signatures from the Issuer and the Receiver each one shall take a copy of the Work Permit.
The Issuer shall keep the copy in his file.
The Receiver shall ensure that permit is available at the worksite or preferably is displayed at a visible location near the worksite, until the job is completed. The Receiver shall also instruct the site supervisor and working crew accordingly.
• It shall be responsibility of both Issuer and Receiver of the Work permit (new as well as renewals) to ensure that:
• All permit conditions are complied with in full at all times. Any deviation, without appropriate authorization, shall result in immediate suspension of the permit.
• When the job is completed, the permits are signed off by the Issuer and Receiver and they exchange the permit copies.
• All Permits issued for equipment are closed prior to startup of the equipment/process.
o Gas Tester shall be an employee who is trained and certified by Safety and is authorized by his department head to conduct gas test.
o Safety Watch / Confined Space Entry Attendant shall be an employee who is trained and certified by Safety and is authorized by his Department head to carry out the activities of Safety watch/Confined space entry attendant.
• Supervisor / in charge of the assigned job, who follows it in the field.
• Vigilance: security /safety officer.
Issuer/Receiver: Same person can’t issue and receive the permit. In case of lone person working in the shift/night, protocol shall be developed for obtaining permission from site in charge/Dept. head to perform job by taking the permit. Site In charge/Dept. Head shall cross check and ensure that necessary controls in place to perform the job.