SiteSorted
Heating and ventilation · United Kingdom

Method statement for rooftop AHU replacement

By SiteSortedBuilt from HSE guidance and CDM 2015 · How we write and check theseUpdated

You must assess the risks of rooftop AHU replacement and record the significant findings if you employ 5 or more people. On CDM sites the principal contractor will ask for RAMS before you start.

RAMS cover the hazards, who could be harmed and how, the controls and the safe sequence of work, and the crew is briefed and signs. The main hazards are falling from a roof edge, falling through a fragile roof or skylight, electric shock from live wiring and public entering the work area.

Make this RAMS nowWord templatePDF

RAMS example: rooftop AHU replacement

This is a complete RAMS for rooftop AHU replacement, with 6 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.

Risk Assessment and Method Statement (RAMS)
Rooftop unit replacement · Heating and ventilation · Example
Document RAMS-001 · Rev 1

Risk assessment

#ActivityHazardsWho might be harmedRisk beforeControlsRisk after
1Plan the crane lift and close the area below
  • Crane and lifting failure
  • Public entering the work area
  • Contact with overhead power lines
Workers, Public, Children, Plant operatorsHigh (12)
  • Barricade the lift zone and keep everyone out from under the load. Isolate
  • Use a crane rated for the load at the radius, set up on firm ground with outrigger pads. Control (engineering)
  • Check slings, chains, shackles and hooks before use. Remove anything damaged or not tagged. Control (engineering)
  • Have a lift plan made by an appointed person, following LOLER. Control (procedures)
  • Use CPCS or NPORS carded crane operators, slingers and signallers. Control (procedures)
  • Fence off the site with secure temporary fencing and lock the gates when you leave. Isolate
  • Give pedestrians a safe, marked path around the work, with ramps for prams and wheelchairs. Isolate
  • Use hoarding, covered walkways or catch fans where work is above public areas. Control (engineering)
  • Put signs at each entry: site name, contact number and "No unauthorised entry". Control (procedures)
  • Make the site safe at the end of each day: cover holes, lower plant, remove ladders and lock tools away. Control (procedures)
  • Ask the distribution network operator (DNO) to turn off, move or insulate the lines before work starts. Eliminate
  • Use non-conductive (fibreglass) ladders near any power lines. Reduce / substitute
  • Mark the safe distance with flags, tape or goal posts and keep all plant and people outside it. Isolate
  • Follow HSE GS6: barriers, goal posts under the lines and a permit for work near them. Control (procedures)
  • Use a dedicated spotter whenever plant moves or raises anything near lines. Control (procedures)
  • Treat all lines as live. If plant touches a line, stay in the cab and keep everyone well away. Control (procedures)
Medium (5)
2Set up roof edge protection or harness anchors
  • Falling from a roof edge
  • Falling through a fragile roof or skylight
Workers, People belowVery high (20)
  • Do what you can from the ground or from a scaffold at the gutter line, for example pre-assemble parts on the ground. Eliminate
  • Install edge protection or guardrails on all open roof edges before work starts. Isolate
  • Use a perimeter scaffold with handrails and toe boards along the eaves where practical. Control (engineering)
  • Where guardrails cannot be fitted, use fall restraint on certified roof anchors so workers cannot reach the edge. Control (engineering)
  • Use one safe, controlled access point and keep others off the roof. Control (procedures)
  • Stop roof work in strong wind or rain, and when the roof is wet, icy or covered in dust or frost. Control (procedures)
  • Wear a harness clipped to a rated anchor when using restraint or fall arrest, and soft-soled non-slip boots. PPE
  • Work from underneath or from a MEWP so nobody stands on the fragile roof. Eliminate
  • Cover or guard every skylight and fragile sheet with a fixed, marked cover or mesh before work starts. Isolate
  • Use safety nets or a boarded platform under the work, and staging or crawl boards to spread the load on fragile surfaces. Control (engineering)
  • Use fall arrest on rated anchors when working near fragile areas. Control (engineering)
  • Treat all roof sheets as fragile until a competent person confirms they are not. Old fibre cement and plastic sheets are fragile. Control (procedures)
  • Put "Fragile roof" signs at every roof access point. Control (procedures)
  • Never walk on sheets between purlins or along skylights. Stay on boards or staging. Control (procedures)
  • Wear a full body harness clipped to a rated anchor. PPE
Medium (5)
3Isolate power and gas, lock off and label
  • Electric shock from live wiring
  • Gas and fuel lines
Workers, Occupants, PublicVery high (15)
  • Isolate the power before any work. Do not work live. Eliminate
  • Lock out and tag the isolation point with your own personal lock and danger tag. Isolate
  • Prove dead at the point of work with an approved voltage indicator (GS38), and prove the tester before and after. Control (engineering)
  • Only competent, qualified electricians do electrical work, following a safe isolation procedure. Control (procedures)
  • Check for back feeds from solar, batteries and generators that can keep a circuit live after the main switch is off. Control (procedures)
  • If live work cannot be avoided, use a permit, a safety observer and insulated tools. Control (procedures)
  • Wear insulated gloves, arc-rated clothing and a face shield when testing or working near live parts. PPE
  • Isolate and purge the line before work, with the owner's approval. Eliminate
  • Lock off and tag the isolation valve. Isolate
  • Check for leaks with a gas detector before and during work, and ventilate the area. Control (engineering)
  • Only Gas Safe registered engineers work on gas fittings. Control (procedures)
  • Remove ignition sources: no smoking, no hot work and no sparking tools near the line. Control (procedures)
  • Know where the shut-off valve is and what to do if a leak happens. Control (procedures)
  • Wear safety glasses and gloves, and keep a fire extinguisher close by. PPE
Medium (5)
4Recover refrigerant before disconnecting
  • Refrigerant leaks
Workers, OccupantsMedium (8)
  • Recover refrigerant into an approved cylinder before opening the system. Never vent it. Isolate
  • Ventilate closed spaces and use a leak detector during the work. Control (engineering)
  • Only F-gas certified engineers handle refrigerants. Control (procedures)
  • With flammable refrigerants (such as R32 or R290), remove ignition sources and use spark-free tools. Control (procedures)
  • Wear cold-rated gloves and safety glasses or a face shield. PPE
Low (4)
5Lift out the old unit and set the new one, keeping clear of the load
  • Crane and lifting failure
  • Falling tools and materials
  • Strong wind and storms
Workers, Public, People belowHigh (12)
  • Use tag lines to control loads and agree on clear radio or hand signals. Control (procedures)
  • Stop lifting in high wind or when the operator cannot see the signaller. Control (procedures)
  • Never ride on a load or hook. Control (procedures)
  • Crane and lifting failure: see step 1 for the full controls Control (procedures)
  • Barricade and sign the drop zone under overhead work so nobody walks beneath. Isolate
  • Fit toe boards, kick plates and mesh screens on scaffolds and edges. Control (engineering)
  • Use catch fans, debris netting or covered walkways where people pass below. Control (engineering)
  • Tether hand tools when working at height. Control (engineering)
  • Keep platforms tidy. Do not stack materials near edges or above toe board height. Control (procedures)
  • Check the forecast each morning and plan work at height and lifting around the weather. Eliminate
  • Tie down or weigh down loose sheets, panels, boards and rubbish at the end of each shift. Control (engineering)
  • Set wind limits for roof work, platforms and cranes, using the manufacturer's limits, and stop when they are reached. Control (procedures)
  • Stop work and get down in lightning. Wait 30 minutes after the last thunder before going back up. Control (procedures)
  • Check scaffold, fencing and edge protection after strong wind before anyone uses them. Control (procedures)
Medium (8)
6Connect, commission and clean the roof
  • Electric shock from live wiring
  • Poor housekeeping and waste
Workers, Occupants, VisitorsVery high (15)
  • Electric shock from live wiring: see step 3 for the full controls Control (procedures)
  • Order materials to size and send packaging back where you can. Eliminate
  • Put skips and waste chutes close to the work. Control (engineering)
  • Clean as you go, and do a full clean up at the end of each day. Control (procedures)
  • Keep exits, stairs and walkways clear at all times. Control (procedures)
  • Stack materials neatly on level ground, away from edges. Control (procedures)
  • Use a registered waste carrier and keep waste transfer notes for at least 2 years. Keep hazardous waste such as asbestos separate, with consignment notes (special waste in Scotland). Control (procedures)
  • Wear gloves when handling waste. PPE
Medium (5)

Method statement: sequence of work

  1. Plan the crane lift and close the area below
  2. Set up roof edge protection or harness anchors
  3. Isolate power and gas, lock off and label
  4. Recover refrigerant before disconnecting
  5. Lift out the old unit and set the new one, keeping clear of the load
  6. Connect, commission and clean the roof

PPE

Safety bootsSafety helmetFull body harness and lanyardHi-vis vestRigger glovesSafety glassesSun protection (sunscreen and neck cover)Insulated electrical glovesArc-rated clothing and face shieldFace shield

Plant and equipment

Mobile crane: CPCS or NPORS crane operator card, plus slinger signaller card; lift plan by an Appointed PersonHand toolsElectrical test equipment (multifunction tester)Extension ladder

Permits and plans

Lift plan (LOLER reg 8)Roof access permitWork at height permitPermit to work (electrical isolation)

Emergency

Call 999. Add the nearest A&E, the assembly point and the first aider for your site.

Sign-off

Supervisor and every worker sign to confirm they have read and understood this RAMS.

Free RAMS template for rooftop AHU replacement

Word (.docx) and PDF, A4 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 RAMS

Pre-start checklist for rooftop AHU replacement

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

The safe sequence of work

  1. Plan the crane lift and close the area below
  2. Set up roof edge protection or harness anchors
  3. Isolate power and gas, lock off and label
  4. Recover refrigerant before disconnecting
  5. Lift out the old unit and set the new one, keeping clear of the load
  6. Connect, commission and clean the roof

Hazards to watch on rooftop AHU replacement

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

Step 4Refrigerant leaksRefrigerant gas causes frostbite, pushes oxygen out of small rooms, and some types catch fire.
Step 2Falling through a fragile roof or skylightA worker steps on a skylight, clear sheet or old fibre cement roof and falls through to the floor below.
Step 1, 5Crane and lifting failureA load falls or swings, or the crane tips, crushing workers under or near the lift.
Step 1Contact with overhead power linesA ladder, MEWP, crane, tipper or long length of material touches or gets close to an overhead line and electrocutes people.
Step 3Gas and fuel linesDamaging or opening a gas or fuel line causes a leak, fire or explosion.
Step 5Strong wind and stormsWind blows sheets, panels and people off roofs and scaffolds, and storms and lightning make work at height and lifting unsafe.
Very likelyLikelyPossibleUnlikelyVery unlikelyHow bad it could be: Negligible to FatalBA
Highest risk on rooftop AHU replacement: Very high before controls (B), down to Medium after controls (A), on the United Kingdom 5 by 5 risk matrix (likely and fatal becomes unlikely and major 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):

  • Will anyone work at height, anywhere a fall could hurt them?
  • Will anyone use a ladder or stepladder?
  • Will anyone work on a roof?
  • Will you use a scaffold or mobile tower?
  • Will you use a MEWP (scissor lift or cherry picker)?

Licences and legal requirements in United Kingdom

Equipment on this job that needs a licence, ticket or training:

  • Mobile crane: CPCS or NPORS crane operator card, plus slinger signaller card; lift plan by an Appointed Person

Employers must assess the risks of their work and record the significant findings (required where you employ 5 or more people). On CDM projects, contractors give their RAMS to the principal contractor before starting, and brief the workers on it.

Rules that apply: Lifting Operations and Lifting Equipment Regulations 1998 (LOLER); CDM Regulations 2015; HSE GS6 Avoiding danger from overhead power lines; Work at Height Regulations 2005; Work at Height Regulations 2005, regulation 9 (fragile surfaces); Electricity at Work Regulations 1989; Gas Safety (Installation and Use) Regulations 1998; Fluorinated Greenhouse Gases Regulations 2015; Work at Height Regulations 2005, regulation 10 (falling objects).

Why RAMS get rejected

Principal contractors send documents back for these reasons. This example avoids them, but check yours too.

  • The method statement is only a list of headings that repeats the risk table and never says how the work is done.
  • The method sequence does not match the risk assessment, for example the method strips the roof before the scaffold is handed over.
  • Residual risk is still High after controls with no extra measures or explanation.
  • It reads as copied: another firm, another address, or wording that does not fit UK sites. HSE warns that copying an example and adding your name does not satisfy the law.
  • Work on an older building with no reference to an asbestos survey.
  • Plant and access equipment listed with no inspection, thorough examination or competence evidence.
  • No briefing record, no revision history, or no named supervisor.

Questions

Do I need RAMS for rooftop AHU replacement?

You must assess the risks of rooftop AHU replacement and record the significant findings if you employ 5 or more people. On CDM sites the principal contractor will ask for RAMS before you start.

Who signs the RAMS?

The person who wrote it and the person who approved it sign and date it. Every worker signs the briefing register after it is explained to them, and the principal contractor reviews and accepts it before you start.

How long do I keep it?

Keep this RAMS, every revision and the signed briefing register with the site file for the length of the job, and keep a copy in your records afterwards.

What PPE is needed for rooftop AHU replacement?

Usually Safety boots, Safety helmet, Full body harness and lanyard, Hi-vis vest, Rigger gloves, Safety glasses, Sun protection (sunscreen and neck cover), Insulated electrical gloves, Arc-rated clothing and face shield, Face shield. The site rules may add more, so check with the principal contractor.

More heating and ventilation RAMS

RAMSAir Conditioning Installation10 stepsRAMSDucted Air Conditioning6 stepsRAMSBoiler Replacement6 stepsRAMSAir Conditioning Maintenance5 stepsRAMSDuctwork Installation5 stepsRAMSF-Gas Leak Repair6 steps

Related jobs in other trades

RoofingRe-RoofingAlso involves contact with overhead power linesScaffoldingScaffold ErectionAlso involves contact with overhead power linesDemolitionSoft StripAlso involves electric shock from live wiringBricklayingBrickworkAlso involves strong wind and stormsElectricalConsumer Unit ReplacementAlso involves electric shock from live wiring

Toolbox talks for this job

Toolbox talkOverhead Power LinesToolbox talkExtension Leads and Power ToolsToolbox talkCrane and Lifting Safety

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

Sources