| Occupied house: household members (Mrs Okafor, family, visitors and any pets) entering the work area, touching hot pipework, tools, open pipework or materials | Mrs Okafor and any other occupants, including children, older or vulnerable people and pets, who could be burned, cut, trip over tools, or be exposed to dust and fumes | Gas Safe registered engineer in charge; operatives wear ID | 3×3=9 | Agree the work area and the route with Mrs Okafor at the pre-start walk. Close the kitchen/utility door where possible and keep the household and pets out of the room while gas is off and while drilling or soldering. Tools, materials and chemicals are kept in the work area or the van, never left unattended. Dust sheets and floor protection are laid. No operative leaves open pipework or an unfinished appliance unattended. Safety boots and gloves worn by operatives. | Low |
| Live gas: gas escape, fire or explosion when disconnecting the old boiler, making new connections and re-establishing the supply | Operatives, Mrs Okafor, household members and neighbours, who could suffer burns, blast injuries or fatal injury | Work by Gas Safe registered engineer under the Gas Safe (Installation and Use) Regulations 1998 | 3×5=15 | Isolate at the emergency control valve and the appliance valve, and cap off open pipework straight away. Check for gas smell before starting. No naked flame, smoking or ignition sources while pipework is open. Ventilate the room. Carry out a gas tightness test and purge to the manufacturer's instructions and standards before re-lighting. Check the meter and emergency control valve are accessible before starting. Use leak detection fluid on all joints. Use the gas tightness test gauge only if calibrated and in date. Keep an extinguisher accessible. | Medium |
| Carbon monoxide and combustion products spilling from an incorrectly fitted or terminated flue, or poor combustion | Mrs Okafor and all household members, who could suffer CO poisoning from the day of installation onwards, which can be fatal | Gas Safe registered engineer; manufacturer's instructions | 2×5=10 | Fit and terminate the flue to the manufacturer's instructions, checking clearances to openings and boundaries. Seal and support all flue joints and check all seals. Use the flue gas analyser to check combustion readings and flue integrity at commissioning, and do not hand over the boiler if readings are not satisfactory. Confirm a working CO alarm is in place and tell Mrs Okafor about the symptoms of CO poisoning. Tell the household not to use the boiler if there are any problems. | Medium |
| Live electricity: contact with live conductors when isolating the boiler and making the electrical connection | Operatives and household members, who could receive an electric shock or burns, which can be fatal | 18th Edition qualified operative; Electricity at Work Regulations 1989 | 3×5=15 | Isolate at the consumer unit or fused spur and lock off with a warning notice. Prove dead with a GS38 compliant voltage indicator proved before and after use. Do not work on or near live parts. Check cable routes before drilling to avoid hidden cables. Make the connection to BS 7671 and complete dead tests before re-energising. Tell the household the supply is off and not to switch it on. Insulated tools used where a risk of contact remains. | Medium |
| Live water: scalding from hot system water when draining, flooding and damage to the house when disconnecting and refilling | Operatives and household members, through scalds and slips, and Mrs Okafor through damage to her property | Hose and bucket in the van | 3×3=9 | Allow the system to cool before draining. Isolate the water supply and agree the drain point before starting. Run the hose to a suitable outlet and secure it. Keep towels and a bucket ready, and lay absorbent sheets under joints. Drain slowly and have the second operative watch the hose. Check all joints for leaks before leaving. Dispose of dirty water as set out in the environmental section. Gloves and eye protection worn. | Low |
| Manual handling of the old and new boilers and pipework in the kitchen/utility and through the house | Operatives, who could suffer back, shoulder or other musculoskeletal injury, or trap hands or drop the boiler | Two operatives on the job | 4×3=12 | Check the weight of the new boiler in the manufacturer's instructions and plan under the Manual Handling Operations Regulations 1992. Remove the boiler casing and any other parts to reduce the load. Use a two-person lift and a sack truck where possible. Clear and check the route from the van to the boiler position. Use a lifting method that avoids awkward reaches. Take breaks between heavy lifts. Gloves and safety boots worn. | Medium |
| Working at height from a step ladder to reach the flue, the boiler on the wall and high-level pipework | Operatives, who could fall and suffer serious injury | Step ladder in good condition | 3×4=12 | Under the Work at Height Regulations 2005, keep work at height to a minimum and do as much as possible from the floor. Check the step ladder before use and use it on firm, level ground with the legs fully open. Keep three points of contact and do not overreach. Use a ladder suited to short duration work only and do not use it for heavy or two-handed tasks. Use a second operative to foot the ladder where needed. Keep the household away from the ladder. For flue termination outside, use a suitable stable platform if the step ladder is not suitable. | Low |
| Respirable crystalline silica (RCS) dust from drilling, coring or fixing into masonry, brick, block or mortar for the flue hole and bracket fixings | Operatives doing the work, and Mrs Okafor and any household members nearby, who could breathe the dust and suffer long-term lung disease | Cordless drill; dust sheets | 3×4=12 | Plan the work to reduce cutting and drilling, for example by using the existing flue hole or the minimum number of fixings. Use on-tool extraction with an M-class or H-class vacuum or water suppression on every drill, core drill or saw used on these materials. Keep others out of the room and close the door. Clean up with an H-class or M-class vacuum, never by dry sweeping or compressed air. Then wear RPE with an assigned protection factor of at least 20 (FFP3 disposable or equivalent), face-fit tested and worn clean shaven. Controlled under the Control of Substances Hazardous to Health Regulations (COSHH) 2002 and HSE guidance: Construction Information Sheet CIS36 'Construction dust'. The RCS workplace exposure limit is 0.1 mg/m3 (8-hour TWA) in HSE EH40/2005. | Medium |
| Disturbing unidentified asbestos-containing materials when drilling, cutting or removing existing building fabric, old flue pipes, boxing, or boiler insulation or gaskets | Operatives, Mrs Okafor and household members, who could breathe asbestos fibres, with serious long-term lung disease | Gas Safe registered engineer; experience of older properties | 2×5=10 | Check before work starts under Regulation 5 of the Control of Asbestos Regulations 2012: ask Mrs Okafor for any asbestos register, survey or information for the boiler area and flue route. If the house was built before 2000 or its age is unknown, and the intrusive area is not covered, a refurbishment survey of that area is needed before drilling or breaking into the fabric. Stop-work rule: if suspect material is found, stop, keep people away, close the room and report it to Mrs Okafor and Halewood Heating Services Ltd before work carries on. Do not sweep, vacuum or handle suspect material. This is a check to be made, not a finding. | Medium |
| Fire from the blowtorch when soldering copper joints near combustible materials, and flux fumes | Operatives and household members, through burns, fire spread and fume inhalation | Fire extinguisher in the van | 3×4=12 | Use press fittings where they are suitable, so no flame is needed. Where soldering is needed, use a heat resistant mat and shield, remove or protect combustibles, and keep a fire extinguisher at hand. Open windows for ventilation. Check behind the work after soldering and leave the area for a time before leaving. Keep the household out of the work area. Gloves and safety glasses worn. | Low |
| Flue termination and external wall penetration: damage to the structure, falling debris, hot flue gases and tools falling to the ground outside | Operatives, Mrs Okafor, household members and neighbours or passers-by outside, through falling tools or debris, or damage to the house | Gas Safe registered engineer; manufacturer's flue instructions | 2×3=6 | Mark out the flue position and check clearances to windows, doors, boundaries and the ground before drilling. Check for cables and pipes within the wall. Keep the ground below the work clear and the household away. Seal and make good around the flue. Tell the client about the final flue position. Safety boots and gloves worn. | Low |
| Slips, trips and falls over tools, hoses, cables, dust sheets, spilled water and materials in the hallway and kitchen/utility | Operatives and household members, who could be injured by falling | Operatives tidy as they go | 3×2=6 | Plan the work area and route before starting. Keep walkways clear and use trailing cable-free cordless tools where possible. Secure dust sheets so they do not slip. Wipe up water straight away. Tidy at the end of each task. Wear safety boots with good grip. | Low |
| Noise and vibration from drilling and coring, and dust and debris in the eyes | Operatives and household members nearby, through short-term noise exposure and eye injury | Cordless drill; short duration of use | 3×2=6 | Under the Control of Noise at Work Regulations 2005, keep drilling and coring to the minimum and tell the household beforehand. Use the correct sharp bit and keep tool use short. Pick a time of day for noisy work that suits the household. Safety glasses worn and hearing protection if noise is high. | Low |
| Cuts, scrapes and burns from sharp pipe ends, boiler casing, flue components and hot pipes | Operatives, through cuts, abrasions and burns | Hand tools in good condition | 3×2=6 | Deburr and file pipe ends before fitting. Allow hot pipework and components to cool before handling. Use the correct tool for each task. Keep a sharp blade guarded when not in use. Gloves worn as backup, and first aid kit in the van. | Low |