Introduction to Hot Work
Hot work refers to any activity that generates flames, sparks, or high temperatures capable of igniting flammable materials, vapors, or dust.
What is Hot Work?
Hot work is any operation involving open flames, spark-producing tools, or heat-generating equipment.
It can create a fire or explosion hazard.
Purpose of Hot Work Permit
Hot Work Permit acts as a safety control system to protect people, property, and processes during hazardous hot work activities.
It control and authorize high-risk activities involving heat, sparks, or open flames to prevent accident.
It ensures:
Hazards are identified and assessed before hot work starts
Safety precautions are implemented in advance
Flammable materials are removed or isolated
Gas testing and ventilation are done where required
Fire watch and firefighting arrangements are in place
Roles and responsibilities are clearly defined
Work is performed in compliance with legal and safety standards
Examples of Hot Work in Industry
Welding
Welding is a fabrication process that joins metals by using high heat, with or without pressure and filler material, to form a strong permanent bond.
Gas cutting
Gas cutting is a process that uses a fuel gas and oxygen flame to heat metal to its ignition temperature and cut it by rapid oxidation.
Grinding
Grinding is a mechanical process that uses a rotating abrasive wheel to cut, smooth, or shape metal and other materials.
Brazing and soldering
Brazing joins metals using a filler metal melted above 450°C without melting the base metal.
Soldering joins metals using a low-melting filler metal, usually below 450°C.
Flame heating
Flame heating is a process where an open flame is used to heat metal or equipment for bending, loosening, shaping, drying, or thermal treatment.
Torch cutting
Torch cutting is a metal cutting process that uses an oxygen-fuel flame to heat metal to its ignition point and cut it through rapid oxidation.
Bitumen heating
Bitumen heating is the process of applying direct or indirect heat to bitumen or asphalt to make it flowable for application, mixing, or coating.
Any activity producing sparks or high heat
Why Hot Work is Dangerous
Hot work can:
- Fire hazards
- Explosion hazards
- Toxic gas release
- Oxygen deficiency
- Burns and heat stress
- Electric shock
- Radiation hazards
- Flying sparks and molten metal
Roles & Responsibilities
Permit Issuer
Verifies site conditions and hazards
Ensures all safety controls are in place
Issues the permit only after compliance
Defines scope, location, and validity
Permit Receiver
Understands permit conditions
Follows all safety instructions
Uses approved tools and PPE
Stops work if unsafe conditions arise
Fire Watcher
Monitors for sparks, smoke, or fire
Keeps firefighting equipment ready
Maintains watch during and after work
Raises alarm in case of emergency
Safety Officer
Conducts risk assessment
Ensures legal and safety compliance
Verifies gas testing and controls
Audits permit implementation
Maintenance Team
Performs the hot work safely
Uses proper tools and PPE
Follows permit conditions strictly
Reports hazards immediately
EHS Department
Develops hot work procedures
Trains employees and contractors
Monitors compliance
Investigates incidents
Area Owner
Provides area clearance
Ensures removal of flammables
Confirms isolation of equipment
Accepts area back after job completion
Permit issue procedures
Who Issues the Permit?
The permit is issued by the Shift Engineer / Shift In-charge/ Area Owner / Authorized Supervisor / Safety Officer after verifying site conditions and hazards.
Who Approves the Permit?
The permit is approved by the Competent Authority (Department Head / EHS Head / Plant In-charge) to ensure all safety controls are in place.
Who Executes the Permit?
The permit is executed by the Authorized worker or contractor performing the hot work under defined safety conditions.
Validity of Permit
A hot work permit is valid only for a specific job, location, and time period (usually one shift or same day). It becomes invalid if conditions change.
Permit Closure Process
After completion of work:
Area is inspected for fire or hazards
Fire watch time is completed
Equipment is made safe
All tools are removed
Permit is signed off and formally closed
Housekeeping restored
Components of a Hot Work Permit
- Job description
- Location details
- Equipment details
- Type of hot work
- Date & time
- Gas test requirement
- Fire watch assignment
- PPE checklist
- Area preparation checklist
- Emergency contacts
- Signatures & authorization
- Obtain valid Hot Work Permit before starting
- Conduct risk assessment of the work area
- Remove or isolate flammable materials
- Ensure proper isolation, blinding, and lockout
- Perform gas testing before and during work
- Maintain adequate ventilation
- Use approved tools and equipment
- Wear appropriate PPE
- Assign a trained fire watcher
- Keep fire extinguishers ready and accessible
- Barricade the area and restrict entry
- Display warning boards and signage
- Maintain good housekeeping
- Stop work if unsafe conditions arise
- Follow permit conditions strictly
- Conduct post-work fire watch
- Close permit after area is declared safe
Pre-Hot Work Safety Checklist
Area free from flammable and combustible materials
Oil, grease, dust, and waste removed
Drains, pits, trenches, and openings covered/sealed
Nearby containers, tanks, and pipelines isolated
No gas/vapour accumulation in the area
Fire-resistant blankets/screens installed where required
Fire extinguisher placed within reach
Safe access and escape routes available
Adequate lighting provided
Barricading and warning signage installed
Non-involved persons restricted from area
Floor dry and non-slippery
No live electrical exposure nearby
Weather condition safe (for outdoor work)
Area free from flammable, explosive, and combustible materials
All wood, paper, plastic, chemicals, solvents removed
Oil, grease, paint, sludge cleaned from floor and surfaces
Drains, pits, sumps, cable trenches covered or sealed
Nearby manholes, ducts, openings protected
No leaking valves, flanges, or joints nearby
Adjacent tanks, vessels, pipelines emptied, cleaned, and isolated
No vapor, fume, or gas smell in surrounding area
Proper natural or forced ventilation provided
Wind direction checked (for outdoor hot work)
Spark arresting screens placed where required
Fire extinguisher easily accessible
Fire hose line available if high-risk area
Clear emergency exit paths maintained
No obstruction to walkways and ladders
Adequate illumination in the work zone
Barricades, cones, tapes installed
Warning boards displayed (HOT WORK IN PROGRESS)
Restricted entry for unauthorized persons
Non-slip, dry floor condition
No water stagnation near electrical sources
Nearby equipment shut down if required
Sensitive instruments protected from heat/sparks
No overhead combustible structure exposed
Fire load minimized in surrounding 15 m area
Emergency access clear for fire team
Explosion-proof zone compliance
No combustible dust accumulation on beams, ledges, or floors
False ceilings / panels checked for hidden combustibles
Wall claddings / insulation not flammable or protected
Nearby storage racks cleared or shielded
Cable trays free from oily rags, papers, plastic
Rubber hoses, gaskets, linings protected from sparks
Nearby paint, thinner, adhesive areas isolated
Compressed gas cylinders stored at safe distance
Waste bins removed from hot work zone
Wooden pallets / crates removed
Packaging material cleared
Nearby laboratory / chemical areas isolated
Battery rooms / charging areas restricted
Vent outlets not directing fumes into confined spaces
Exhaust fans working properly
No confined space opening exposed
Sewer lines / hydrocarbon drains isolated
Static electricity sources controlled
No hot surfaces nearby that can ignite materials
Roof area checked for bitumen, tar sheets
Rainwater downpipes checked for vapors
No LPG/PNG lines passing through work zone
Nearby safety showers/eyewash unobstructed
Fire alarm call point accessible
Smoke detectors temporarily isolated (if required & approved)
Sprinkler heads not blocked
Fire doors not wedged open
Emergency assembly route clear
Public access blocked (if common area)
Sound level safe for emergency communication
No reflective glare affecting vision
Temperature and heat build-up manageable
No loose debris that can catch sparks
No flammable insulation on nearby pipes
Nearby HVAC ducts protected from spark entry
Drain covers non-sparking
Nearby stored oxygen removed
No pressurized vessels in vicinity
Fire load reassessed after housekeeping
Gas Testing & Atmospheric Monitoring
Why gas testing is required
To detect flammable, toxic, or oxygen-deficient atmospheres before they cause fire, explosion, or health hazards.
LEL and UEL
LEL (Lower Explosive Limit): Minimum gas concentration that can ignite.
UEL (Upper Explosive Limit): Maximum gas concentration above which ignition cannot occur.
Oxygen level limits
Safe range: 19.5% – 23.5%.
Below 19.5% = oxygen deficiency; above 23.5% = increased fire risk.
Toxic gas limits
Must be within permissible exposure limits (PEL/TLV). Any value above limits is unsafe for work.
Gas detectors (portable & fixed)
Portable: Used for spot checks and confined spaces.
Fixed: Continuous monitoring in high-risk areas.
Frequency of gas testing
Before starting hot work, periodically during work, and after breaks or condition changes.
Recording gas test results
All readings must be documented on the permit with date, time, location, and tester’s signature.
Emergency Response During Hot Work
Fire emergency steps
Stop work, raise alarm, use suitable extinguisher if safe, isolate energy sources, evacuate if fire spreads.
Explosion emergency steps
Stop all activities, move to safe distance, alert emergency team, avoid ignition sources, follow site emergency plan.
Burn injury first aid
Cool the burn with clean running water, do not apply ointments, cover with sterile dressing, seek medical help.
Electric shock first aid
Disconnect power if safe, do not touch victim with bare hands, check breathing, give CPR if trained, call emergency services.
Emergency communication
Immediately inform control room, fire team, and supervisor using designated emergency numbers or alarms.
Evacuation procedure
Follow marked escape routes, do not run, assemble at muster point, report to supervisor, wait for further instructions.
Fire Watcher Concept
Who is a fire watcher?
A trained person assigned to continuously monitor the hot work area to detect and respond to any fire or unsafe condition.
Responsibilities
Observe for sparks, smoke, or fire; keep firefighting equipment ready; raise alarm; stop work if unsafe; report incidents immediately.
Required training
Fire prevention, use of fire extinguishers, emergency response, hazard recognition, and permit conditions.
Equipment required
Appropriate fire extinguishers, fire blanket, whistle/communication device, PPE, and torch (if required).
Duration of fire watch
Throughout the hot work activity and as specified in the permit.
Post-work fire watch
Continue monitoring the area for a defined period after work completion to ensure no smoldering or delayed ignition.
Hot Work Permit -Legal & Regulatory Requirements
- Prevent fires and explosions
- Protect life and property
- Comply with safety laws and standards
- Avoid legal penalties and shutdowns
- Meet OSHA, Factories Act, NFPA, PESO, and GMP requirements
