14 Alder View

1 Recommendations

In priority order. Each carries the standard it comes from, where it applies, and the evidence photographed on the day.

1

Adjust the cylinder thermostat so stored water is maintained at 60 °C, and check any immersion heater thermostat separately

Stored hot water was recorded at 53.4 °C. Hot water should be stored at 60 °C. Below this, Legionella is suppressed but not reliably killed, and cooler layers within the cylinder sit inside the range in which the bacteria multiply.

Confirm the heating runs long enough to reach it, then retest.

ACoP L8 · HSG274 Pt2 para 2.82

High · 30 days

2

Fit a close-fitting lid to the cistern

The storage tank lid was loose or ill-fitting. An unsealed tank allows dust, debris, insects and light to enter, all of which support bacterial growth.

HSG274 Pt2 Table 2.1

High · 30 days

3

Remove, clean and descale the head and hose, or replace if heavily fouled

Heavy scale was present on the shower head in the bathroom (first floor). Showers are the only outlets in most homes that produce a respirable spray, and scale provides both shelter and nutrients for bacteria.

Then descale quarterly.

Location: Bathroom (First floor)

HSG274 Pt2 Table 2.1

High · 3 months

5

Cut the redundant section back to the nearest point of flowing water, leaving no dead end

Redundant pipework was identified in the Kitchen — Capped feed under the sink where a dishwasher was removed. Water within it never moves and cannot be flushed by normal use. A length exceeding twice the pipe diameter is sufficient to hold water indefinitely.

Capping the pipe close to the fitting does not remove the stagnant volume.

Location: Kitchen

HSG274 Pt2 Table 2.1

Medium · 3 months

6

Establish why turnover is low: the tank may be oversized for the property's actual use

The stored water in the tank was 18.6 °C against an inlet temperature of 14.1 °C — a gain of 4.5 °C over the incoming supply. Water that has warmed this far above its own feed is standing in the tank long enough to gain heat from its surroundings, which indicates poor turnover.

Where the stored capacity is not needed, consider removing the tank and converting the outlets it serves to mains supply, ensuring no redundant pipework is left behind.

HSG274 Pt2 Table 2.1 — stored water turnover

Medium · 3 months

7

Disconnect the filling loop at one end and store it, reconnecting only when the system needs repressurising

The heating system filling loop at the boiler in the kitchen was found connected. The flexible hose links the mains drinking supply to the sealed heating circuit; left in place it is both a stagnant length of pipework that will not be replenished in normal use, and a route by which inhibitor-dosed heating water could be drawn back into the drinking supply if the mains pressure drops.

Confirm a double check valve is fitted where it tees off the mains cold supply.

Water Supply (Water Fittings) Regulations 1999 · HSG274 Pt2

Medium · 3 months

8

Shorten the branch so the filling loop connection sits as close to the live mains pipe as practicable

The mains branch serving the heating system filling loop measures 18 cm. This branch tees off the live cold water supply but carries almost no flow, so the water within it stands still and is not replenished by normal use — the same condition as any other dead leg, at the point where the drinking supply meets the heating system.

Ideally within 10 cm. Where it cannot be shortened, flush it through by opening the filling loop briefly on a regular basis, and record when this is done.

HSG274 Pt2 Table 2.1 — redundant pipework

Medium · 3 months

9

Disconnect and drain the hose after each use and store it off the ground

A hose was left connected to the outside tap. Water standing in a hose warms quickly in sunlight and is discharged as spray at first use; if the open end lies in a water butt, pond, puddle or container, a drop in mains pressure can draw that water back toward the drinking supply.

Confirm a double check valve is fitted to the outside tap.

Water Supply (Water Fittings) Regulations 1999

Medium · 3 months

10

When these are next disturbed or replaced, use WRAS-approved hoses or rigid copper

Braided flexible connector hoses serve the fittings in the Kitchen. The rubber lining of many flexible connectors is EPDM, a material bacteria colonise readily as it ages and pits. Braided flexible connector hoses serve the fittings in the Bathroom (First floor). The rubber lining of many flexible connectors is EPDM, a material bacteria colonise readily as it ages and pits.

No urgent action is needed — check their condition at routine visits and replace any that are perished, kinked or past their stated life.

Applies to: Kitchen, Bathroom (First floor)

HSG274 Pt2 — materials of construction; WRAS

Low · 6 months

11

Insulate the visible run of the incoming main, and check the insulation remains continuous and undamaged at routine visits

The visible pipework at the incoming main is not fully insulated. The incoming supply is the coldest water in the house, and bare pipework lets it warm towards room temperature before it reaches a single tap.

HSG274 Pt2 — insulation of cold water services

Low · 6 months

2Assessment of the Risk

This property has a traditional stored-water system: cold water held in an open storage tank in the loft, above the landing, and hot water stored in a vented cylinder fed from it. Water stands still in two places here rather than passing straight through, and the cold store is open to its surroundings — which is why a system of this design starts from a higher baseline than one where little or no water is stored, or where the store is sealed, before anything is found wrong with it. Storage alone does not make a system high risk: a modern sealed cylinder held at 60 °C, for example, can assess as low risk. It simply means the condition and temperatures of the stores decide the outcome.

What raises it above that baseline is specific to this visit: sediment in the cistern, which gives bacteria something to feed on; hot water stored at 53.4 °C rather than 60 °C, which suppresses Legionella without reliably killing it; and redundant pipework holding water that never moves.

Legionella causes illness only when several things line up: bacteria get in, the water sits at a temperature that lets them multiply, that water is then broken into a breathable spray, and somebody breathes it. At this property the first two links are present — water is stored, and it is not being held at the temperatures that would keep numbers down — and the third is the shower in the bathroom (first floor). That sequence, rather than any single reading on its own, is what this assessment is about.

It is worth saying what has not been found. Legionella multiplies between 20 °C and 45 °C, and fastest in the upper half of that range. The stored water here was measured at 53.4 °C and 18.6 °C — outside the limits, but not inside the range in which numbers build quickly. That is the difference between a system that needs correcting and one that is actively dangerous, and it is why the rating is moderate rather than higher.

Completing the three priority actions above breaks the chain at the point where it is easiest to break — the conditions that let numbers build. The remaining actions reduce what can get in and what can stand still.

3Property and Water System Description

The property is a semi-detached house, built between 1970 and 2000, arranged over two floors, with three bedrooms, of brick construction. It was occupied at the time of the survey by two residents.

Water enters the property from the public mains, with the internal stop tap located under the kitchen sink. The incoming supply pipe is copper, and the supply was recorded at 15.2 °C.

Cold water is stored before use. A cistern is located in the loft, above the landing, holding approximately 68 litres at the water level recorded, calculated from its measured dimensions. The stored water was 18.6 °C, against 14.1 °C at the inlet — a difference of 4.5 °C.

Hot water is stored in a vented cylinder, fed from the cold water cistern rather than directly from the mains. The cylinder is located in the airing cupboard, holding approximately 143 litres calculated from its dimensions, and stored water was recorded at 53.4 °C.

Water is distributed to six fittings across two rooms (Kitchen, Bathroom (First floor)). Of these, the shower in the bathroom (first floor) produces a breathable spray, and is therefore the point at which the system could expose anyone to airborne water.

5Water System Assets

Each asset that supplies, stores, heats or treats water, with the detail and photographs recorded at the survey. Values outside the standards applied are shown in red.

Incoming Mains Supply

Stop tap	Under the kitchen sink
Stop tap operation	Turns freely
Pipe material	Copper
Insulation of visible run	Bare — no insulation
Supply temperature	15.2 °C

See recommendation 11.

Cold Water Storage Cistern

Location	Loft, above the landing
Stored volume	≈68 litres, calculated from the measured water level
Lid	Loose or gapped
Insulation	None
Internal condition	Light sediment
Stored water temperature	18.6 °C
Temperature at inlet	14.1 °C

See recommendations 2, 6.

Hot Water System

Type	Vented cylinder, fed from the storage cistern
Location	Airing cupboard
Capacity	≈143 litres, calculated from its dimensions
Stored water temperature	53.4 °C
Insulation	Partial
Immersion heater	Fitted

See recommendations 1, 4.

Other Plumbed Equipment

Outside tap and hose

6Hot and Cold Water Distribution

Hot water should reach 50 °C within one minute at the outlet and be stored at 60 °C; cold should be below 20 °C within two minutes. Throughout this document a reading or note shown in red falls outside those limits or needs attention; green marks a reading in range or a protective feature present.

7Satisfactory at This Assessment

Not Established at This Assessment

These do not change the risk rating, but should be captured at the next visit.

8Standards Applied

The standards this property's water system is judged against — only those applying to the system actually found here are listed. These are the figures set out in the guidance named beside each, not house rules.

A domestic property is not required to hold a temperature monitoring regime in the way a commercial building is. These figures are the standard against which the system was judged on the day, and the target any corrective work should achieve.

9Scope and Limitations

What this document is. This is a Legionella risk assessment for an ordinary domestic dwelling. It identifies and categorises the risk from Legionella bacteria so that it can be managed, based on what could be seen and measured at the property on the date of the survey. It is not a certificate, not a guarantee of safety, and not confirmation that the system is free of Legionella. No such document exists: the risk from Legionella can be controlled, but never wholly eliminated.

Who carried it out, and on what footing. HSE guidance for residential landlords states: "Most landlords can assess the risk themselves and do not need to be professionally trained or accredited", and that this duty "does not require an in-depth, detailed assessment" (hse.gov.uk — Legionella and landlords' responsibilities; Crown copyright). This assessment was carried out on that basis by the person named below, using the DwellFlow platform. DwellFlow structures the survey, applies the temperature and control thresholds set out under Standards Applied, reads the completed survey back in full to check that it holds together, and produces this document from what was recorded. It does not attend the property and it does not verify what was recorded there.

What was not examined. The survey was non-intrusive and limited to accessible, visible areas. Pipework concealed within walls, floors, boxing or the roof void was not inspected, so further redundant sections may exist. No water samples were taken — routine Legionella sampling is not normally required for a domestic property of this type, and HSE guidance states that health and safety law does not require a landlord to obtain a "legionella test certificate". Temperatures were recorded on one occasion and represent conditions at that moment. Any item recorded as not established is listed in this document, and is a limitation of the assessment rather than a finding of safety.

Premises outside this scope. This assessment is for a domestic dwelling. Premises registered as a care home or a children's home are commercial premises and require assessment by a trained, competent Legionella risk assessor; this document is not suitable for them. Neither is it suitable for communal or shared water systems serving more than one dwelling, such as the storage tanks, booster sets or communal hot water plant of a block of flats. Where any of those were identified they are recorded here for referral, not assessed.

Where the duty sits, and the limits of our liability. Under the Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations 2002, the duty to assess and control the risk rests with whoever is responsible for the property. That duty cannot be transferred — not to the person who surveyed, and not to DwellFlow. This document exists to inform the duty holder; acting on it remains theirs. The assessment reflects the property as found on the date of survey, and alterations, changes of use or changes of occupancy after that date are not covered by it. DwellFlow provides the platform and the method, and is not liable for loss arising from information recorded inaccurately or incompletely at the property, or from recommendations in this document not being acted upon. Nothing in this document limits or excludes liability for death or personal injury caused by negligence, for fraud, or for anything else which cannot lawfully be limited or excluded.

11About Legionnaires' Disease

Legionella bacteria occur naturally in rivers, lakes and groundwater, and in very small numbers in mains drinking water. At those numbers they are harmless. They become a risk only when conditions in a building's own water system allow them to multiply, and the water is then inhaled as a fine spray.

Three conditions have to coincide. The water must sit somewhere between 20 °C and 45 °C, the range in which the bacteria multiply. It must remain there long enough for numbers to build — stagnation in a little-used outlet, a redundant length of pipe, or a storage vessel that turns over slowly. And it must then be dispersed as a breathable aerosol, which in a home means principally a shower, a spray tap or a spa bath.

Legionnaires' disease is a form of pneumonia. It cannot be caught from another person, and it cannot be caught by drinking water. People over 45, smokers, and those with a weakened immune system or an existing lung or heart condition are more susceptible than the general population, which is why the vulnerability of occupants forms part of the risk score. Anyone concerned about their health should speak to their GP or NHS 111.

12References and Further Reading

This assessment cites the clause behind each recommendation. The full documents are available as follows, and are worth reading in full by anyone responsible for a property.

14Document Control