Legionella

Location

In this course, the following programme is followed -
• Legionella - what it is
• The need for a risk assessment
• Who should carry out the risk assessment
• The risk assessment
• Understanding domestic water systems

Completion of this course can be counted as 5 hours continuous professional development for the London Landlord Accreditation Scheme or for any other body which accepts our CPD courses.

Legionella - What It Is
Legionellosis is a collective term for diseases caused by Legionella bacteria including the most serious Legionnaires’ Disease, as well as the similar but less serious conditions of Pontiac Fever and Lochgoilhead Fever. Legionnaires’ Disease is a potentially fatal form of pneumonia and everyone is susceptible to infection. The risk increases with age, but some people are at higher risk, eg people over 45, smokers and heavy drinkers, people suffering from chronic respiratory or kidney disease, diabetes, lung and heart disease or anyone with an impaired immune system.

Sources Of The Bacteria
The bacterium Legionella Pneumophila and related bacteria are common in natural water sources such as rivers, lakes and reservoirs. They may also be found in purpose-built water systems, such as hot and cold water systems and spa pools. If conditions are favourable, the bacteria may multiply, increasing the risks of Legionnaires’ Disease, and it is therefore important to control the risks by introducing appropriate measures.

Contracting Legionella
Legionnaires’ Disease is normally contracted by inhaling small droplets of water (aerosols), suspended in the air, containing the bacteria which is why showers and spa baths are higher risk. There is no risk from drinking contaminated water nor can it be passed person to person.

Annual Cases
There are around 300 - 500 cases per year although around half of those are associated with travel rather than being contracted in England or Wales. The mortality rate is around 12% and in particular people who become affected have a weak immune system. Males appear to be more affected than females.
Contributory factors are:
• compromised immune
• elderly
• smokers
• lack of exercise

Annual cases of legionella

Causal Chain
A chain of events must take place for a person to be affected by legionella.
The table below shows the causal chain.

Causal Chain Legionella

In order for the bacteria to multiply, there needs to be a period of stagnation of water at the right temperatures with nutrients for the bacteria to feed off. Then, there must be some generation of an aerosol. Next, the aerosol must be inhaled. Finally, some people are more susceptible than others (such as elderly, smokers etc.)
The below table looks at what an assessment of the risk should be looking at in this causal chain.

Means of control

As can be seen, the primary means of control is the multiplication part of the chain. If that can be stopped , the next link in the chain wouldn’t be reached.
A landlord or agent has limited control over the aerosol being produced (people will always want showers) and inhaling can’t be prevented. Also, it’s out of a landlord or agents control whether a person has a compromised immune system or is in some other way at a higher risk.
Conditions Increasing Risk
Some of the conditions that increase the risk of the bacteria multiplying which will be covered in detail later include -
• water temperature between 20 and 45 degrees (the highest rate of multiplication is 37 degrees)
• water droplets that can be inhaled
• water that is stored
• water that is circulated
• deposits in water storage such as -
? rust
? sludge
? scale
? organic matter
? biofilms

Golden Rules
When carrying out an assessment the following golden rules should be kept in constant mind -
• keep the hot hot
• keep the cold cold
• keep the water moving
• keep the water clean

Keeping to these golden rules will ensure the risk of multiplication is reduced to a minimum if not eliminated altogether.

The Need For A Risk Assessment
In this section we will consider the statutory background and show the legislation which requires an assessment of the risk to be carried out.
The legal framework -
• Health and Safety at Work etc. Act 1974
• Control of Substances Hazardous to Health Regulations 2002 (COSHH regulations)
• Approved Code of Practice L8 (Fourth Edition) - Legionnaires’ disease. The control of legionella bacteria in water systems (ACOP)
• Technical Guidance HSG274 - Part 2: The control of legionella bacteria in hot and cold water systems 

Health and Safety at Work etc. Act 1974
Section 2(1) of the Act provides - 
(1) It shall be the duty of every employer to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all his employees.
This section would ordinarily apply to letting agents and provides the duty to ensure all employees are reasonably safe (including from legionella - see later).
Section 3(1) titled General duties of employers and self-employed to persons other than their employees provides -
(1) It shall be the duty of every employer to conduct his undertaking in such a way as to ensure, so far as is reasonably practicable, that persons not in his employment who may be affected thereby are not thereby exposed to risks to their health or safety.

This subsection of section 3 provides that all employers must ensure all persons not in his employment are safe. This will include tenants and would again ordinarily apply to letting agents as they are more likely to employ persons (but it also applies where a landlord employs).
Section 3(2) goes onto to provide -

(2) It shall be the duty of every self-employed person to conduct his undertaking in such a way as to ensure, so far as is reasonably practicable, that he and other persons (not being his employees) who may be affected thereby are not thereby exposed to risks to their health or safety.

This subsection provides that all self-employed persons* must ensure he and other persons* are safe. This is what typically affects landlords. Ordinarily they will be a self-employed person and any other person will include the landlord’s tenants. This sub-section also catches smaller letting agents working on a self-employed basis with or without employees.

The Health and Safety at Work etc. Act 1974 provides a general overarching duty and then regulations made under the Act will narrow down what is ‘reasonably practicable’ in respect of particular duties.

For legionella purposes, the regulations narrowing down the duty are the Control of Substances Hazardous to Health Regulations 2002.
Control of Substances Hazardous to Health Regulations 2002 (COSHH)
Regulation 3(1) of the COSHH regulations provides (highlights added) -
(1) Where a duty is placed by these Regulations on an employer in respect of his employees, he shall, so far as is reasonably practicable, be under a like duty in respect of any other person, whether at work or not, who may be affected by the work carried out by the employer except that the duties of the employer— 

These regulations catch all persons with a duty but uses the term ‘employer’ throughout. Therefore, whenever the term ‘employer’ is used, it includes any other person, whether at work or not who has a duty.
Regulation 6 continues -
An employer shall not carry out work which is liable to expose any employees to any substance hazardous to health unless he has— 

This is the regulation that requires a ‘suitable and sufficient assessment of the risk’ by all persons with a duty. We call this a ‘risk assessment’ for short.
Although the term ‘employer’ is used, remember back to regulation 3 which provides that ‘employer’ means any other person with a duty (so will include self-employed persons for example).

Regulation 6 then goes on to define what is a suitable and sufficient assessment of the risk and provides that the risk assessment shall include consideration of -
• the hazardous properties of the substance;
• information on health effects provided by the supplier, including information contained in any relevant safety data sheet;
• the level, type and duration of exposure;
• the circumstances of the work, including the amount of the substance involved;
• activities, such as maintenance, where there is the potential for a high level of exposure;
• the effect of preventive and control measures which have been or will be taken;
• such additional information as the employer may need in order to complete the risk assessment.

Approved Code of Practice L8 (Fourth Edition) - Legionnaires’ disease. The control of legionella bacteria in water systems (ACOP)
The ACOP guidance gives guidance and help on producing a risk assessment in respect of legionella. The guidance is approved by the board of the Health and Safety Executive and although not specifically legislation - if followed will be a discharge of the duty provided for by the Health and Safety at Work Act and the COSHH regulations. A landlord or agent doesn’t have to follow the guidance if they can show what they are doing is better than that provided for within the guidance.

The guidance was amended in May 2013 and this brought smaller residential properties into the duty by removing the 300 litre size of water storage. Since May 2013, the guidance applies to all water systems (not just those with greater than 300l water storage).
HSG274 Technical Guidance
HSG274 is the accompanying set of guidance which is more technical in nature and is split into three parts.

For most landlord or agent duties, Part 2: The control of legionella bacteria in hot and cold water systems will be the required part.

Who Should Carry Out The Risk Assessment
In respect of who should carry out the assessment, there are ‘dutyholders’ and ‘responsible persons’.
Dutyholders
The dutyholder is the person who has a ‘duty’ under the Health and Safety at Work Act as shown earlier.
The landlord will always be a dutyholder because they will either be an employer or self-employed and their work can potentially affect the safety of any other person i.e. their tenants.
Where there is also a letting or managing agent the position becomes less clear. Is the landlord the dutyholder or is the agent? It is respectfully submitted that in this situation there are two equal dutyholders. An agent is a dutyholder because they are an employer (or self-employed person) with a duty to ensure any other person is safe from their work i.e. the tenants that the agent puts into a property. In respect of the letting agent, not only does their duty extend to tenants placed in properties but also to their staff when conducting viewings or contractors when requesting work be carried out.
The position becomes difficult for an agent if a landlord has been told about their need to carry out a legionella risk assessment but refuses. What should the agent do? Is that a discharge of their duty just be informing the landlord of their duty? No is the answer. It is submitted the agents duty still remains to ensure all persons affected by their work are safe and that a suitable and sufficient assessment of the risk be conducted.

Where a landlord refuses to carry out the risk assessment, it is submitted the agent should think along the same lines as to what action they would take if the landlord refused to carry out a gas safety check. In principle there is no difference as they are both statutory duties.
Responsible Person
The dutyholder can nominate a ‘responsible person’ to carry out a risk assessment and then monitor its revisions and work requested. The dutyholder and responsible person can be the same person.
Commonly a landlord might nominate the letting agent as the responsible person which is fine. A letting agent might nominate itself or use an outside body such as a plumber to carry out an assessment or any works found to be necessary after an assessment has been completed.
Inventory clerks appear to be getting heavily involved in providing a legionella risk assessment service.
Knowledgeable And Competent
Ultimately, the person who carries out the risk assessment (or any works sought after the assessment is completed) must be knowledgeable and ‘competent’.
The ACOP guidance provides -
The appointed competent person or persons should have sufficient authority, competence and knowledge of the installation to ensure that all operational procedures are carried out in a timely and effective manner. Where the dutyholder does not employ anyone with the necessary competence, they may need to appoint people from outside the organisation. In such circumstances, the dutyholder should take all reasonable steps to ensure the competence of those carrying out work who are not under their direct control and that responsibilities and lines of communication are properly established and clearly laid down.
It is hard to define precisely what is ‘competent’. It will include (but not be limited to)
• adequate training
• understanding of water systems
• understanding of water heating and storage
• real life experience

The ACOP guidance defines competent as including -
Training is an essential element of an employee’s capability to carry out work safely, but it is not the only factor: instructions, experience, knowledge and other personal qualities are also relevant to perform a task safely. 
The Risk Assessment
In this section the following are considered -
• when to carry out the assessment
• low risk
• identifying the risk
• preventing and controlling the risk
• recording the risk
• reviewing the risk assessment
• video of a risk assessment

When To Carry Out The Assessment
There are many opportunities to carry out a risk assessment. It could be done at the next periodic inspection of the property. If the property is empty, it could be done before re-letting. If a plumber is to carry out the assessment and the gas safety record is due soon, the assessment could be done at the same time.
The tenancy agreement should be consulted as to what notice a tenant will need to be given before entering but as a general rule, at least 24 hours’ notice in writing will be needed.
Tenants have responsibilities too and an information leaflet should be provided explaining when they should regularly discharge unused outlets for example.
Low risk
All systems require a risk assessment, however not all systems will require elaborate control measures. A simple risk assessment may show that the risks are low and being properly managed to comply with the law. In such cases, you may not need to take further action, but it is important to review your assessment regularly in case of any changes in your system, and specifically if there is reason to suspect it is no longer valid. (para 25 ACOP guidance)
An example of low risk given by the ACOP guidance is -
• in a small building without individuals especially ‘at risk’ from legionella bacteria;
• where daily water usage is inevitable and sufficient to turn over the entire system;
• where cold water is directly from a wholesome mains supply (no stored water tanks);
• where hot water is fed from instantaneous heaters or low volume water heaters (supplying outlets at 50 °C);
• where the only outlets are toilets and wash hand basins (no showers).

Importantly note from above if a property has a shower or is not a combination boiler it will NOT be classed as ‘low risk’ for the purpose of the ACOP guidance and instead WILL possibly need more measures to be considered. These measures may not be much but nonetheless necessary to comply with the duty.
Identifying the risk

What should the assessment include
A risk assessment should -
• identify the system
• identify all risk factors
• provide recommendations
• record the assessment
• be regularly reviewed

Identifying the risk
The risk assessment should identify and evaluate potential sources of risk and:
• the particular means of preventing exposure to legionella bacteria;
• or if prevention is not reasonably practicable, the particular means of controlling the risk from exposure to legionella bacteria.

There are a number of factors that create a risk of someone acquiring legionellosis, such as:
• the presence of legionella bacteria;
• conditions suitable for growth of the organisms, eg suitable water temperature (20 °C–45 °C) and deposits that are a source of nutrients for the organism, such as sludge, scale, rust, algae, other organic matter and biofilms;
• a means of creating and spreading breathable droplets, eg the aerosol generated by showers or spa pools;

The following list contains some of the factors to consider in a simple residential property, as appropriate, when carrying out the risk assessment:

• Look for dead legs (a water pipe that has been capped off). If there are any these they should be recorded as the stale water contained in them can be a source of multiplication at the right temperatures. Ideally the plumber should be engaged to remove these deadlegs.

Deadleg

• What temperature is the hot water set at on the boiler and / or cylinder? (Legionella breeds at between 20 and 45 degrees)
? What are the temperatures of the water from the outlets? No risk assessment can be completed successfully without measuring these temperatures in our view. For a small landlord or agent, a simple £20.00 thermometer probe should be sufficient but if doing more, a more professional thermometer will be more appropriate.


Preventing And Controlling The Risk
The following list will assist with recording the risk assessment recommendations for preventing and controlling legionella.
When considering what action might be needed to reduce the risk, the first consideration must always be to eliminate the risk entirely. If the risk cannot be removed entirely, it must then be managed by recommendations (for example tell the tenant to keep the hot water set at 60 degrees). Any recommendations must be effective and should be proportionate to the risk.
For example, it is proportionate and effective to visually inspect for dead-legs and require removal. That is both effective and proportionate to eliminate the risk from dead-legs entirely. However, it would not necessarily be proportionate to require a new oak floor be lifted to check whether any dead-legs are present under the floor.
Water storage
• If a water tank is present, this should be recorded. Tanks should have a well fitted lid to prevent contamination. They should be clean inside and lagged to prevent heating above 20 degrees in the summer months. The temperature of the water in the tank should be recorded on the assessment. Take care when inspecting in lofts.
• Fortic tanks pose a higher risk and should be recommended to be removed at the earliest available opportunity (where proportionate).

Dead-legs
• If there are dead-legs (pipes that are capped off), these should be noted and then removed. The stale water contained within the dead-leg can assist the breeding of legionella and as the bacteria has a tail, it can swim out and into the water system.

Temperatures
• What is the temperature of the hot water set at? Legionella breeds at between 20 and 45 degrees so ideally the temperature on the cylinder or combination boiler should be set at 60 degrees (but no more than 60 for fear of scalding)
• The temperatures from the cold water taps should be recorded on the assessment and be below 20 degrees. Legionella does not multiply below this temperature. Include all outlets for example outside taps and unused utility rooms.
• The temperatures from hot outlets should be recorded on the assessment and be above 50 degrees. This temperature and above kills the legionella bacteria. The temperature should not exceed 60 degrees for a fear of scalding (somewhere around 55 is about perfect).
• Hot tip: when testing showers, it’s difficult because the spray produces inaccurate results. Take the head off the shower and then test the water temperature. You will save lots of time! Remember too that many showers have thermostatic valves which may prevent the water coming out of the hose without it mixed with cold water. It would be reasonable and proportionate to use the water in a nearby tap in this is a problem.
• Hot tip 2: when checking temperatures from a combination boiler you may find the hot is below 50 degrees. This might be because the flow rate of the cold going into the boiler is too fast. This in turn means it’s going through the boiler too quickly to heat up to temperature. In this case ask your plumber to turn down the flow rate on the cold inlet until you can achieve 50 degrees when the tap is turned on full.

Tenant’s information
• Are there outside taps or unused rooms with taps? The tenant should be advised to run unused outlets at least weekly.
• Do the tenants go away for extended periods of time? If so, they need to be advised if away longer than a week to heat the hot water to 60 degrees for one hour and then run the water through for 5 minutes. When tenants have been away for a period, tenants should be advised to put the shower head in the bath before running the water through.
• Showers are the highest risk because of the droplets that can become stagnant in the head and because they cause a spray. It is the inhalation of the spray that infects people (you can’t become infected by drinking contaminated water). As a result, shower heads should be dismantled, disinfected and cleaned thoroughly at least quarterly or as indicated by the rate of fouling.
• Tenants can be given a leaflet explaining all of these recommendations at the time of the assessment if not already done and then all new tenants should be given an information leaflet. The providing of such information is sufficient for the purpose of the ACOP guidance.

Spa pools
Spa pools, whirlpool baths, spa baths or hot tubs should ideally be removed altogether as they pose the highest risk due to their operating temperatures and spray produced. The occupiers must be advised to disinfect according to the manufacturers instructions.
See for example a case where three people died after a display Hot Tub in a garden centre wasn’t cleaned properly.
Void periods
• During void periods, outlets should be run at least weekly during viewings. If the property is empty for longer than 6 weeks, the hot water should be heated to at least 60 degrees for one hour and then all hot outlets run through for at least 5 minutes. The cold water should be run through for 5 minutes. For a period of longer than 6 weeks, consideration should be given to having the system professionally cleaned.

Change of tenancy
• At a change of tenancy, the void period guidance should be followed and the temperatures on the boiler and hot water cylinder (if one) should be checked to ensure the previous occupiers didn’t turn the temperatures down. At each change of tenant you should consider if the new tenant is significantly more vulnerable and if the existing control measures are appropriate. The temperatures and cleanliness should still be checked regardless of a change in the vulnerability of the occupier.

Recording The Risk
All of the above and anything else referenced in the ACOP guidance should be entered onto the risk assessment form along with any remedial action recommended and taken. For example, the risk assessment could identify a water tank in the loft which has no lid. This is an increased risk and the assessment should recommend a lid be fitted. The assessment can be further updated once the lid has been fitted thus reducing the risk.   There are apps for phones and tablets such as this one to make the entering of the information much easier and quicker. A sample report produced by that app is available here.   The ACOP guidance provides:
Once the risk has been identified and assessed, a written scheme should be prepared for preventing or controlling it. In particular, the written scheme should contain the information about the water system needed to control the risk from exposure. However, if it is decided that the risks are insignificant and are being properly managed to comply with the law, you may not need to take any further action. But it is important to review the risk assessment regularly and specifically if there is reason to suspect it is no longer valid, for example changes in the water system or its use.
Reviewing the risk assessment
A review of the risk assessment should be carried out regularly and whenever there is reason to suspect that it is no longer valid for example if there is:
• a change to the water system or its use;
• a change to the use of the building where the system is installed;
• new information available about risks or control measures;
• the results of checks indicating that control measures are no longer effective;
• changes to key personnel;
• a case of legionnaires’ disease / legionellosis associated with the system.

Video of risk assessment

Understanding Domestic Water Systems
Here we provide some images and diagrams of typical water systems - see if you can understand them.
Part 2 of the HSG274 should be consulted for more diagrams and more in-depth information about each type of water system.
Smaller Hot And Cold Water Systems

Combination and instantaneous hot water

Combination boilers or instantaneous water heaters provide hot water directly from the cold water supply by heating the water as it passes through the heater. These units supply continuous hot water at a rate that is usually limited by their power rating. High flow rates through the units can result in warm water leaving the heater before reaching the target temperature. 
Fortic Tank

Fortic tank

In some combination units, the header tank is split into two sections: one feeding the water heater below and the other supplying cold water to the closed heating system. Possible cross-contamination and poor temperatures should be considered as part of the risk assessment. 
Gravity-Fed

Gravity fed system without recirculation

Gravity systems without recirculation are generally installed in domestic dwellings and small buildings. Cold water enters the building from a rising main and is stored in a cold water tank. The cold water tank provides backflow protection to the mains supply and a stable pressure and reserve in the system if the mains pressure fails or demand exceeds the capacity of the mains supply. Cold water from the tank is fed to the calorifier (hot water cylinder) where it is heated and drawn via pipes that branch to sinks, washbasins, baths, showers etc. In contrast to recirculating systems, the water only flows when it is being used and is usually allowed to become cool in the pipes after use.
Pressurised Systems

Pressurised system

These systems are fed directly by a pressurised supply (sometimes via a break tank and booster set) connected to the water heater or heat exchanger. In these systems, water expands when heated, requiring an expansion vessel, safety temperature and pressure relief valve (in a pressurised hot water system there is no open vent to a high level).

---

Venue Facilities

---

Directions