Fire Safety During Hot Work Operations
The Problem
Hot work operations—such as welding, cutting, grinding, and brazing—are common tasks on many sites, but they’re also one of the leading causes of fires and explosions. These activities produce sparks, heat, and molten material, which can ignite nearby combustible materials and lead to serious injury, property damage, or fatalities. Today, we’ll identify these hazards and review fire safety procedures aligned with WorkSafe NZ best practice guidance.
Identify the Hazards
- Sparks and Heat: Sparks from hot work can ignite materials up to 10 metres (35 feet) away.
- Flammable Materials: Dust, gases, or liquids near the hot work area present a significant fire risk.
- Heat Transfer: Heat can travel through metal structures and ignite combustibles on the opposite side.
- Improper Fire Watch: Skipping post-work monitoring may allow hidden fires to smoulder and flare up.
- Confined Spaces: Flammable vapours or poor ventilation greatly increase the risk of explosion.
Safety Practices and Preventative Measures
1. Authorisation and Pre-Work Inspections
- Obtain a Hot Work Permit before starting any work outside designated hot work zones.
- Conduct a hazard inspection to identify combustible materials or flammable vapours.
- Where possible, perform hot work in designated fire-resistant areas.
2. Fire Protection Equipment
- Ensure that fire extinguishers, water hoses, or buckets of sand are on hand and operational.
- Use the correct extinguisher type (e.g., Class A, B, or C).
- Train all workers and fire watchers in extinguisher use and emergency procedures.
3. Handling Combustible Materials
- Remove combustible items within a 10-metre radius of the hot work area.
- Protect immovable combustibles using fire blankets, welding curtains, or fire shields.
- Keep the work area clean—remove flammable debris and protect floors with damp sand or fire-resistant sheeting.
4. Preventing Fire Spread
- Seal gaps or cracks in walls, floors, and ceilings to stop sparks escaping.
- Shut down ventilation ducts or conveyors that may carry sparks elsewhere.
- Assign a fire watch to monitor heat transfer through metal walls or structures to adjacent spaces.
5. Fire Watch Requirements
- Assign a trained fire watch when:
- Combustibles are present
- Sparks may spread
- Heat transfer through structures is possible
- Combustibles are present
Fire watchers must:
- Be trained in fire extinguisher use
- Know emergency procedures and alarm locations
- Stay in the area for at least 30 minutes post-work to check for smouldering fires
6. Special Considerations for Equipment and Spaces
- Clean tanks, drums, or pipes thoroughly to remove flammable residues before beginning hot work.
- Ensure proper ventilation in confined spaces and monitor air quality using gas detection equipment.
- Never carry out hot work in explosive atmospheres or areas with active flammable gases or dust.
Real-Life Case or Scenario
On one site, sparks from grinding ignited sawdust and flammable materials that had built up on the floor. The fire spread rapidly, causing serious property damage and putting workers in danger. It was later determined that combustibles hadn’t been cleared and no fire watch had been assigned. The incident could have been avoided with better preparation and follow-up.
Employee Responsibilities
- Confirm all permits and inspections are completed before starting.
- Remove or shield combustible materials before starting work.
- Use fire extinguishing gear correctly and keep it nearby.
- Follow fire watch procedures, including monitoring after the work is completed.
- Report any unsafe conditions or faulty gear right away.
Employer Responsibilities
- Provide hot work permits and ensure hazard assessments are done properly.
- Supply suitable fire safety equipment and ensure workers are trained in its use.
- Appoint and train fire watchers for relevant tasks.
- Monitor ventilation and test air quality before work in confined spaces.
Discussion & Questions
- “What’s your standard routine before starting hot work to keep the area safe?”
- “Has anyone experienced a near-miss or fire incident related to hot work? What happened and what did we learn?”
Encourage your team to share experiences and raise concerns or suggestions for improving procedures.
Commitment/Action Plan
Let’s commit to checking the work area for combustibles, securing fire permits, and following every hot work safety step before starting any task. Each person on site plays a role in ensuring fire prevention.
Wrap-Up
Fire prevention during hot work is essential for protecting people, property, and productivity. By following these practices and complying with WorkSafe NZ regulations, we can reduce the risk of fire and make our worksites safer for everyone. Thanks for taking safety seriously.
Standards Overview
Under the Health and Safety at Work Act 2015 (HSWA) and WorkSafe guidance:
- PCBUs must manage risks from hot work, including fire and explosion risks.
- A Hot Work Permit must be issued for any welding, grinding, or cutting done outside designated safe areas.
- Fire watches, ventilation, and fire safety equipment must be in place and used correctly.
- Pre-work inspections and training are essential to meeting legal duties and protecting workers.
Disclaimer
These toolbox talks are provided for informational and educational purposes only and are not a substitute for professional legal, health and safety, or regulatory advice.
The content reflects recognised best practices and general industry standards as at the date of publication. However, it may not be applicable to all workplace environments or specific operational contexts.
It is the responsibility of the Person Conducting a Business or Undertaking (PCBU), as well as officers, workers, and other duty holders under the Health and Safety at Work Act 2015 (HSWA), to ensure compliance with all relevant laws, regulations, and WorkSafe New Zealand guidance.
The authors, presenters, and distributors of this toolbox talk disclaim all liability for any loss, damage, or injury arising from the use or reliance on the information provided. Users should seek advice from a suitably qualified health and safety professional or legal advisor for guidance tailored to their specific circumstances.
Always follow your organisation’s policies, procedures, and safe work practices to manage risks and maintain a safe and healthy workplace.
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