Plumbing · Canada

FLHA for water heater replacement

By SiteSortedBuilt from provincial OHS law and CCOHS guidance · How we write and check theseUpdated November 9, 2026

Provincial OHS law requires hazards to be assessed and controlled before work starts. A field level hazard assessment (FLHA) for water heater replacement is done on site at the start of the shift and again whenever conditions change.

It lists the tasks, hazards and controls, and every worker signs on before starting and signs off at the end of the shift. The main hazards are electric shock from live wiring, fire from hot works, lifting and carrying heavy loads and gas and fuel lines.

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FLHA example: water heater replacement

This is a complete FLHA for water heater replacement, with 10 job steps. Open it in the builder to add your site, crew and signatures, change anything, and download a PDF. Or download the free Word template below and fill it in by hand.

Field Level Hazard Assessment (FLHA)

Replace a water heater · Plumbing · Example

Document FLHA-001 · Rev 1

Job steps, hazards and controls

#	Job step	Hazards	Risk before	Controls	Risk after
1	Check access to the unit and plan the removal route through stairs, roof spaces or tight cupboards	Tight spaces: attics and crawl spaces Lifting and carrying heavy loads	High	Do as much of the work as you can from outside the tight space. Elimination Turn the power off at the panel before entering where you can, as damaged wiring may be live. Engineering (guarding) Lay crawl boards across the joists so you cannot step through the ceiling. Engineering Set up ventilation and lighting in the space. Engineering Limit time in hot attics and take breaks somewhere cool. Administrative Tell someone when you go in and when you are out. Administrative Wear a dust mask, knee pads, gloves and a bump cap. PPE Plan to avoid carrying: have materials delivered, and old items picked up, as close as possible to where they are used. Elimination Use lighter or smaller loads: order smaller bags and shorter lengths, and drain or break down old items before moving them. Substitution Use trolleys, pallet jacks, hoists, vacuum lifters or equipment instead of carrying by hand. Engineering Use a two-person lift for anything heavy, long or awkward. Plan the route first and clear it. Administrative Keep the load close, back straight and no twisting. Turn with your feet. Administrative Rotate tasks and take breaks on long lifting jobs. Administrative Wear gloves for grip and safety boots to protect your feet. PPE	Medium
2	Isolate power at the electrical panel and gas or water at the meter, apply lockout and tags	Electric shock from live wiring Gas and fuel lines Stored energy	Critical	Isolate the power before any work. Do not work live. Elimination Lock out and tag the isolation point with your own personal lock and danger tag. Engineering (guarding) Test before you touch: prove dead at the point of work with a tested voltage tester. Engineering Only licensed electricians do electrical work, to the Canadian Electrical Code and provincial rules. Administrative Check for back feeds from solar, batteries and generators that can keep a circuit live after the main switch is off. Administrative Isolate and purge the line before work, with the owner's approval. Elimination Lock off and tag the isolation valve. Engineering (guarding) Gas and fuel lines: see step 8 for the full controls Administrative Release or block all stored energy before work: release the pressure in pipes, tanks and hoses, bleed hydraulics, release springs, lower loads. Elimination Lock out and tag all energy sources with personal locks. Engineering (guarding) Put mechanical blocks or props under raised parts like buckets, tipper bodies and doors. Engineering Test that the system is dead and nothing can move before you start. Administrative Follow the maker's procedure, for example for garage door and roller door springs. Administrative	Medium
3	Drain the old unit, watching for scalding water and steam	Hot water and steam Burns from hot surfaces Slips and trips	Medium	Turn the system off and let it cool before work. Elimination Isolate and lock off the heat source and valves, and release the pressure. Engineering (guarding) Hot water and steam: see step 9 for the full controls Administrative Isolate heating systems and let parts cool before you touch them. Elimination Fit guards or insulation on hot pipes and equipment. Engineering Mark hot items with chalk or a "HOT" sign so others know. Administrative Keep a first aid kit and cool running water nearby for burns. Administrative Wear heat-resistant gloves and long sleeves. PPE Plan walkways and keep them clear of materials, hoses and leads. Elimination Run leads and hoses overhead on hooks or stands, or along walls, not across walkways. Engineering Fill or cover holes, and lay boards or mats on muddy access paths. Engineering Clean up offcuts, packaging and spills as you go, not at the end of the day. Administrative Keep work areas, stairs and access paths well lit. Administrative	Low
4	Disconnect pipes, flue and wiring, and cap the gas line	Gas and fuel lines Electric shock from live wiring Cuts from sharp edges	Critical	Check for leaks with a gas detector before and during work, and ventilate the area. Engineering Only licensed gas fitters work on gas lines. Administrative Gas and fuel lines: see step 8 for the full controls Administrative If energized work cannot be avoided, use a permit, a safety observer and insulated tools, following CSA Z462. Administrative Wear insulated gloves, arc-rated clothing and a face shield when testing or working near live parts. PPE Electric shock from live wiring: see step 2 for the full controls Administrative Deburr or cover sharp edges, and fit edge protectors on exposed sheet metal. Engineering Use knives with retractable or self-retracting blades. Engineering Cuts from sharp edges: see step 5 for the full controls Administrative	Medium
5	Remove the old unit using a trolley and two people	Lifting and carrying heavy loads Cuts from sharp edges	High	Lifting and carrying heavy loads: see step 1 for the full controls Administrative Deburr or cover sharp edges, and fit edge protectors on exposed sheet metal. Engineering Use knives with retractable or self-retracting blades. Engineering Cut away from your body and keep your other hand clear. Administrative Put used blades in a blade bin or sharps container. Administrative Use two people to handle large sheets of metal or glass. Administrative Wear cut-resistant gloves and long sleeves. PPE	Medium
6	Position and secure the new unit on a level base	Lifting and carrying heavy loads Tight spaces: attics and crawl spaces	High	Lifting and carrying heavy loads: see step 1 for the full controls Administrative Tight spaces: attics and crawl spaces: see step 1 for the full controls Administrative	Medium
7	Make pipe joins, with a hot work permit and an extinguisher at hand if soldering or brazing	Fire from hot works Burns from hot surfaces	Critical	Use cold work methods where you can, such as bolting, press fittings or cutting with a saw instead of a torch. Elimination Move anything that can burn at least 10 metres away, or cover it with fire blankets. Engineering (guarding) Use fire-resistant screens to stop sparks reaching people or gaps in walls and floors. Engineering Get a hot work permit before starting. Administrative Keep a charged fire extinguisher and fire blanket at the work spot. Administrative Keep a fire watch during the work and for at least 60 minutes after you finish. Administrative Check for smouldering behind walls, in ceilings and under floors before you leave. Administrative Wear flame-resistant clothing, welding gloves and eye or face protection. PPE Burns from hot surfaces: see step 3 for the full controls Administrative	Medium
8	Reconnect gas (by a licensed gas fitter) and power (by a licensed electrician), then leak test	Gas and fuel lines Pressure testing Electric shock from live wiring	Critical	Isolate and purge the line before work, with the owner's approval. Elimination Lock off and tag the isolation valve. Engineering (guarding) Check for leaks with a gas detector before and during work, and ventilate the area. Engineering Only licensed gas fitters work on gas lines. Administrative Remove ignition sources: no smoking, no hot work and no sparking tools near the line. Administrative Test with water instead of air or gas where the system allows it. Never put water in refrigerant pipework, which is tested with dry nitrogen. Substitution Keep people out of the test area with signs and barriers. Engineering (guarding) Pressure testing: see step 9 for the full controls Administrative Electric shock from live wiring: see step 2 for the full controls Administrative	Medium
9	Fill and purge air, check the relief valve, commission and set the temperature	Hot water and steam Pressure testing	Medium	Turn the system off and let it cool before work. Elimination Isolate and lock off the heat source and valves, and release the pressure. Engineering (guarding) Check the temperature, and open fittings slowly while facing away. Administrative Keep a first aid kit and cool water ready for burns. Administrative Wear heat-resistant gloves, long sleeves and a face shield. PPE Test with water instead of air or gas where the system allows it. Never put water in refrigerant pipework, which is tested with dry nitrogen. Substitution Keep people out of the test area with signs and barriers. Engineering (guarding) Use a calibrated gauge and a relief valve set to protect the system. Engineering Test to the pressure the system calls for and hold it for the set time. Never go over. Administrative Release the pressure fully before tightening anything or fixing leaks. Administrative Wear safety glasses or a face shield. PPE	Low
10	Take the old unit off site and clean up	Lifting and carrying heavy loads Poor housekeeping and waste	High	Lifting and carrying heavy loads: see step 1 for the full controls Administrative Order materials to size and send packaging back where you can. Elimination Put waste bins and chutes close to the work. Engineering Clean as you go, and do a full clean up at the end of each day. Administrative Keep exits, stairs and walkways clear at all times. Administrative Stack materials neatly on level ground, away from edges. Administrative Wear gloves when handling waste. PPE	Medium

PPE

CSA green triangle safety boots (CSA Z195)Work glovesSafety glasses (CSA Z94.3)N95 respiratorKnee padsHard hat (CSA Z94.1)Face shieldCoverallsWelding glovesCut-resistant gloves

Plant and equipment

Hand toolsPress fitting toolPropane torchTrailer

Permits and plans

Lockout permitHot work permit

Emergency

Call 911. Add the nearest hospital, the muster point and the first aid attendant for your site.

Sign-off

Supervisor and every worker sign to confirm they have read and understood this FLHA, then sign off at the end of the shift.

Free FLHA template for water heater replacement

Word (.docx) and PDF, Letter landscape, no email needed. Fill in your site details, then print or send it.

Word template (.docx)PDF template

Make yours in 2 minutes

Same document, filled in for your job. Answer a few yes or no questions, the crew signs on the phone, and you send the PDF.

Start this FLHA

Pre-start checklist for water heater replacement

Tick these off before work starts. They come from the hazards, permits and equipment in this job.

FLHA read, explained and signed by everyone on the job
Lockout, tagout and test before touch done before work starts
Hot work permit issued, extinguisher at hand, fire watch arranged
First aid attendant, first aid kit and emergency number (911) confirmed
PPE checked and worn: CSA green triangle safety boots (CSA Z195), work gloves, safety glasses (CSA Z94.3), N95 respirator

The safe sequence of work

Check access to the unit and plan the removal route through stairs, roof spaces or tight cupboards
Isolate power at the electrical panel and gas or water at the meter, apply lockout and tags
Drain the old unit, watching for scalding water and steam
Disconnect pipes, flue and wiring, and cap the gas line
Remove the old unit using a trolley and two people
Position and secure the new unit on a level base
Make pipe joins, with a hot work permit and an extinguisher at hand if soldering or brazing
Reconnect gas (by a licensed gas fitter) and power (by a licensed electrician), then leak test
Fill and purge air, check the relief valve, commission and set the temperature
Take the old unit off site and clean up

Hazards to watch on water heater replacement

The hazards most specific to this job, and the step where each one comes up.

Step 3, 9Hot water and steamOpening hot water systems, boilers or steam lines scalds workers.

Step 1, 6Tight spaces: attics and crawl spacesCrawling through attics, crawl spaces or tight ceilings leads to falls through the ceiling, heat stress, shocks and cuts.

Step 3, 7Burns from hot surfacesTouching hot pipes, tools, bitumen, solder or freshly welded metal burns the skin.

Step 8, 9Pressure testingA pipe, fitting or cap fails under test pressure and blows apart, hitting people nearby.

Step 2Stored energyEnergy left in springs, hydraulics, compressed gas, raised loads or capacitors releases suddenly and crushes or injures workers.

Step 7Fire from hot worksSparks and heat from welding, grinding or flame torches set fire to timber, insulation, rubbish or fuel nearby.

Highest risk on water heater replacement: Critical before controls (B), down to Medium after controls (A), on the Canada 5 by 5 risk matrix (possible and fatality becomes unlikely and lost time injury).

What changes on your site

This example covers the job itself. Your site may add more. Add controls for any of these that apply (the builder asks you these as yes or no questions):

Could anyone fall 3 metres or more, or fall any distance into machinery, water, a hazardous substance or through an opening?
Will anyone use a ladder or stepladder?
Will anyone work on a roof?
Is there a fragile roof, skylight or clear roof sheet?
Will you use a scaffold or mobile tower?

Why FLHAs get rejected

Prime contractors and COR auditors send documents back for these reasons. This example avoids them, but check yours too.

End of shift boxes already say "None" when the form was signed at the start of the shift.
One FLHA reused for days or weeks, or a "review by" date a month away, when the work and conditions change daily.
No time of assessment and no record of any revision, which Alberta s.7(3) requires.
Workers signed that they "read" it, but nothing shows they took part, which Alberta s.8(1) requires.
Work at height with no fall protection plan where the province requires one, or no written rescue procedure for workers using fall arrest.
Permits or locates required on site but no permit or ticket numbers recorded.
No re-assessment entry after an obvious change such as weather, a new task or a new crew member.

Rules by province for water heater replacement

Province or territory	Key local rule	Regulator
Ontario	Fall protection (O. Reg. 213/91 s.26) applies at a fall of more than 3 m, more than 1.2 m where the work area is used as a path for a wheelbarrow or similar equipment, and at any height into operating machinery, water or other liquid, a hazardous substance, or through an opening.	Ontario Ministry of Labour, Immigration, Training and Skills Development
British Columbia	Fall protection is required where a fall of 3 m or more may occur (s.11.2). A written fall protection plan is required at 7.5 m or more where there are no permanent guardrails (s.11.3).	WorkSafeBC
Alberta	A hazard assessment must be done before work begins, and before a new work site is built (OHS Code s.7(1)). The results must be written down with the controls (s.7(2)).	Alberta Occupational Health and Safety
Quebec	Guardrails (Safety Code s.2.9.1, as amended by Decret 63-2025) are needed where a worker could fall into liquid or a hazardous substance, onto moving parts or dangerous equipment, 1.2 m or more when using a vehicle, 1.5 m or more when handling a load, and more than 3 m in all other cases.	CNESST (Commission des normes, de l'equite, de la sante et de la securite du travail)
Manitoba	A prime contractor is required whenever more than one employer or self employed person works on the site at the same time (Act s.7).	Manitoba Workplace Safety and Health Branch
Saskatchewan	An occupational health committee is required at 10 or more workers of one employer (Act s.3-22).	Saskatchewan Ministry of Labour Relations and Workplace Safety, OHS Division
Nova Scotia	Workers must be trained in fall protection before using it or working in, supervising or planning work in a fall protection area, with a refresher at least every 3 years (WHSR s.21.19).	Nova Scotia Department of Labour, Skills and Immigration, Safety Branch (OHS)
New Brunswick	Fall protection is needed from 3 m above water or the nearest permanent safe level (Reg 91-191 s.49(1)(a)(i)).	WorkSafeNB
Newfoundland and Labrador	Give written notice to the minister before starting a construction project that will last 30 days or more, with the site, location, type of work and number of workers (Regs s.8).	Government Services, Occupational Health and Safety Division
Prince Edward Island	Fall protection is needed from 3 m above the nearest safe surface or water (Fall Protection Regulations s.2(1)(a)).	Workers Compensation Board of PEI, OHS Division
Yukon	Every employer must do hazard assessments with the committee, representative or workers, and redo them after significant changes or incidents (Regs s.1.03.01).	Yukon Workers' Safety and Compensation Board
Northwest Territories	Fall protection is needed from 3 m, or lower if there is a risk of injury (s.119(1)). Guardrails are needed for falls of 1.2 m to 3 m at permanent work sites (s.119(2)).	Workers' Safety and Compensation Commission (WSCC)
Nunavut	No 911. To reach the RCMP in an emergency, dial your community's first three digits then 1111 (Iqaluit: 979-1111). Put the local fire, ambulance and RCMP numbers on every FLHA.	Workers' Safety and Compensation Commission (WSCC)

Questions

Do I need an FLHA for water heater replacement?

Who signs the FLHA?

The supervisor and every worker take part in the assessment and sign on before work starts, then sign off at the end of the shift. Review it and re-sign whenever the task or conditions change.

How long do I keep it?

Keep completed hazard assessments for at least 3 years (COR auditors sample the last 12 months). Review this FLHA and re-sign whenever the task, crew or conditions change.

What PPE is needed for water heater replacement?

Usually CSA green triangle safety boots (CSA Z195), Work gloves, Safety glasses (CSA Z94.3), N95 respirator, Knee pads, Hard hat (CSA Z94.1), Face shield, Coveralls, Welding gloves, Cut-resistant gloves. The site rules may add more, so check with the general contractor.

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Blank FLHA template: free FLHA templates. Also for other countries: Australia (SWMS) · United Kingdom (RAMS) · United States (JHA)