When Is Fire Watch Required for Hot Work in Ontario?

Fire watch may be required during hot work when an open-flame torch or another ignition source is used for hot surface applications in or on a building and combustible materials are within 5 metres. Where the cited Ontario Fire Code condition applies, the area must be toured by fire-watch personnel at least once each hour. The exact assignment should still be confirmed against the current code, site conditions, and any direction from the authority having jurisdiction.

This article explains the supplied Ontario requirements in practical terms. It is not legal advice, and it does not mean every welding, cutting, grinding, or other hot-work task automatically requires fire watch.

Quick summary

• Hot work includes activities that use open flames or produce heat or sparks, such as welding, cutting, grinding, soldering, brazing, and pipe thawing.
• The cited Ontario Fire Code rule applies when an open-flame torch or other ignition source is used for hot surface applications in or on a building and combustible materials are within 5 metres. Read the Ontario Fire Code provision.
• When fire watch is required under that rule, fire-watch personnel must tour the areas at least once each hour.
• Before work begins, confirm the work area, combustible materials, fire-system status, communication method, responsible contacts, evacuation process, and reporting duties.
• Fire watch is a defined fire-risk assignment. It is not automatically the same as a general security post.

What does fire watch mean during hot work?

Fire watch is an assigned observation and response function intended to identify fire hazards, communicate concerns, notify the right people, and support the site’s emergency procedures. The person assigned should know which areas are included, what conditions to look for, who has authority to stop or escalate work, and how observations will be recorded.

That is different from simply placing a guard near a contractor. A general security post may focus on access control, trespassing, theft prevention, or visitor management. A hot-work fire-watch assignment must also address the fire risk created by heat, sparks, flame, combustible materials, and changing site conditions.

Practical duties may include observing the work and nearby areas, touring the defined coverage zones, maintaining communication with the work crew and site lead, notifying emergency contacts, supporting evacuation coordination, escalating an incident, and documenting activity. The duties should be written before work starts rather than assumed from a job title.

When hot-work conditions create an elevated fire risk, arrange appropriate fire watch coverage with clearly defined observation, notification, evacuation, and reporting responsibilities.

When does the Ontario Fire Code require fire watch for hot work?

The supplied Ontario Fire Code excerpt identifies a specific condition: a fire watch is required whenever an open-flame torch or another ignition source is used for hot surface applications in or on a building, and combustible materials used in building construction or its contents are within 5 metres of people using that torch or ignition source. The same excerpt states that the relevant areas must then be toured by fire-watch personnel at least once each hour.

The 5-metre condition is important because it prevents a broad assumption that every hot-work task has the same fire-watch requirement. A responsible site stakeholder should assess the work, the building, the nearby materials, and the boundaries of the affected area. Other provisions, local requirements, permit conditions, insurer expectations, or fire-department direction may also apply.

Ontario construction-project rules also require precautions to prevent fire when a blow torch, welding or cutting equipment, or similar equipment is used. That reinforces the need to plan the work area and controls in advance, but it does not turn this article into a complete statement of every construction or fire-safety obligation. Review the applicable construction-project regulation and obtain current site-specific guidance where necessary.

Which activities count as hot work?

The Ontario Fire Code hot-work section supplied for this article applies to work that uses open flames or produces heat or sparks. Examples include cutting, welding, soldering, brazing, grinding, adhesive bonding, thermal spraying, and thawing pipes. An activity that does not use an obvious open flame can still create ignition concerns through heat, sparks, or hot surfaces.

Do not decide on fire watch by looking only at the tool. Consider what the tool is doing, where the work is taking place, what materials are nearby, whether the area changes during the job, and how a concern would be reported or escalated.

Hot-work activities and site decisions

Activity	Potential concern	Site decision to confirm
Welding or cutting	Flame, heat, sparks, and hot metal	Are combustible materials within the relevant area, and who will observe and tour it?
Grinding	Heat and flying sparks	Where can sparks travel, and are nearby materials, openings, or work zones protected?
Soldering or brazing	Open flame and heated surfaces	Is the work being performed in or on a building, and what materials are within 5 metres?
Thermal spraying	Heat and potentially ignitable particles	What boundaries, communication method, and escalation instructions apply?
Pipe thawing	Heat applied near building materials or contents	Who checks the surrounding area and records concerns or changes?

This table is a planning prompt, not a substitute for applying the current regulation to the specific task. A row does not automatically establish that fire watch is required. The work method, building conditions, combustible materials, and applicable requirements must be confirmed together.

What must fire-watch personnel do?

Where the cited fire-watch rule applies, the area must be toured at least once each hour. Before assigning that duty, define the area to be toured and make sure the person assigned can identify hazards, communicate promptly, and reach or contact the responsible site lead.

Written post orders or site instructions should clarify:

• Which work areas, adjacent spaces, levels, openings, and material-storage locations are covered.
• What fire, smoke, heat, sparks, odours, damaged equipment, or unsafe conditions must be reported.
• How the fire-watch person communicates with contractors, supervisors, building representatives, and emergency contacts.
• Who can pause the work, initiate escalation, contact emergency services, or coordinate evacuation.
• What activity and incident information must be documented, and where it is sent.
• How changing work conditions are communicated during shift handoffs or contractor changes.

Personnel assigned to hot-work environments should be prepared for hazard recognition, evacuation coordination, and incident reporting. Accure Security describes fire watch protocol training covering those areas, including assignments in hot-work environments. Any provider should be asked how personnel preparation matches the duties and risks of the particular site.

Pre-work hot-work fire watch checklist

Use this checklist with the site supervisor, contractor, building representative, and anyone responsible for emergency coordination:

• Identify the work: Record the task, equipment, location, schedule, contractor, and expected changes to the work area.
• Assess nearby materials: Identify combustible construction materials, contents, waste, packaging, insulation, stored equipment, and concealed or adjacent areas that may be affected.
• Confirm the boundaries: Mark the work zone, nearby areas to observe, access points, floors, openings, and locations that must be toured.
• Check building systems: Confirm the status of fire detection, alarm, sprinkler, suppression, and communication systems, and identify who must be notified about an impairment.
• Assign responsibility: Name the site lead, contractor supervisor, fire-watch personnel, emergency contacts, and the person who can stop or escalate the work.
• Set communication: Agree on radios, phones, check-ins, emergency notification, backup contacts, and the process for reporting a missed communication.
• Define emergency actions: Explain notification, evacuation coordination, access for responders, and escalation steps without relying on informal assumptions.
• Plan documentation: Decide what observations, tours, incidents, instructions, handoffs, and changes will be recorded.
• Brief the team: Review the work area, hazards, boundaries, responsibilities, and changing conditions before ignition, heat, or spark-producing work begins.

How fire watch fits into construction site security

Active construction sites can change from one shift to the next. Contractors may move between work zones, materials may be stored temporarily, access points may change, and equipment or debris may introduce new hazards. A fire-watch plan therefore needs to be updated when the work area or surrounding conditions change.

Fire watch can complement construction site security, but the two assignments are not interchangeable. Construction security may address contractor access, perimeter checks, equipment, materials, patrols, and incident reporting. Fire watch focuses on defined fire-risk observation and the associated communication and emergency procedures.

A project may need both when the site has active hot work and broader security concerns. One plan may assign fire-watch duties around the work area while other personnel manage access points, patrol the perimeter, or protect equipment and materials. The proposal should separate these responsibilities so no one assumes that a general patrol automatically satisfies the fire-watch assignment.

When should you arrange dedicated fire-watch coverage?

Dedicated or contracted coverage may be appropriate when fire systems are impaired, repairs or construction create elevated risk, multiple work zones must be observed, internal staff cannot maintain the required assignment, or the owner needs documented coverage. It may also help after a fire or other high-risk incident when the property needs additional observation and controlled access.

The decision should be based on the site conditions and defined duties, not only on the label “security guard.” Ask the provider to confirm the assignment’s boundaries, touring frequency, communication process, emergency escalation, reporting expectations, and how coverage will adapt if the work moves or conditions change.

Before hot work starts: final decision check

1. Identify whether the work uses an open flame or produces heat or sparks.
2. Determine whether the cited Ontario Fire Code condition applies, including the building setting and combustible materials within 5 metres.
3. Check current code requirements, local direction, work permits, insurer conditions, and any impaired-system procedures relevant to the site.
4. Define the fire-watch area, at least hourly touring requirement where applicable, observation duties, communication method, and escalation authority.
5. Brief the assigned personnel and contractor before the work begins.
6. Document the plan, tours, observations, changes, incidents, and handoffs according to the site’s requirements.

Frequently asked questions

Does grinding count as hot work in Ontario?

Grinding is listed among the supplied Ontario Fire Code examples of hot work that can produce heat or sparks. Whether the cited fire-watch rule applies depends on the work and site conditions, including the building setting, ignition risk, and combustible materials in the relevant area.

Can a regular security guard perform hot-work fire watch?

Not automatically. The person must be suitable for the defined fire-watch duties and prepared to recognize hazards, communicate concerns, support evacuation coordination, follow escalation instructions, and document activity. A general security assignment does not by itself prove that the person has been briefed or prepared for hot-work fire watch.

Is fire watch required when a building’s fire alarm or sprinkler system is impaired?

An impairment can create a separate reason to arrange fire-watch or contractor-watch coverage, but the answer depends on the system, site conditions, applicable requirements, and instructions from the responsible authority or building representative. Confirm the required procedure rather than assuming that the hot-work rule alone answers the question.

Conclusion

Hot-work fire watch in Ontario is a site-specific decision. Start with the work method, then assess the building, ignition source, combustible materials, work-zone boundaries, fire-system status, and responsibilities of everyone involved. Under the cited Fire Code condition, combustible materials within 5 metres of an open-flame torch or other ignition source used for hot surface applications can trigger fire watch, with at least hourly touring of the relevant areas.

If your project needs defined observation, communication, reporting, and escalation duties for hot work, request a site-specific quote from Accure Security for fire-watch coverage in Ontario.