Legionella prevention

The Health and Safety Executive (HSE) state that legionellosis (illnesses caused by the legionella bacteria) are preventable.

A sequence of events leads to people catching diseases and these ‘links in the chain’ can be interrupted, avoided or minimised. In this regard legionella prevention can be achieved.

The Approved Code of Practice known as ACoP L8 covers this on pages 10 – 13 in the section ‘Preventing or controlling the risk from exposure to legionella bacteria’ in paragraphs 52-65.

Once the risk has been identified a written scheme is required for preventing or controlling it. This should have information on how to control the risk from exposure on each site or premises.

It should be acknowledged that legionella prevention is NOT the correct technical term.

Legionella means the bacteria which are common in water and soil and they cannot be prevented at source. Hence they will at some point come into buildings via the mains water system and it is impractical to remove them.

It is crucial that a legionella risk assessment identifies the risk and (subsequently if not already in place) that adequate control measures are carried out. This is very likely to result in prevention of legionellosis which is achievable i.e. prevention of illnesses.

The primary objective is to avoid conditions which permit legionella bacteria to proliferate and also to avoid creating a spray, mist, aerosol or other type of droplet formation.

This in practice means avoiding water temperatures of 20-45°C, stagnant water, any materials that promote organic growth and limiting the systems that produce droplets.

All these steps combine to reduce the risk by effective legionella control measures thus achieving the goal of legionella prevention.

No one wants cases of Legionnaires’ disease or other legionellosis because of the huge negative outcomes associated with the publicity. It is critical therefore to have appropriate systems and procedures in place. Archer + Stone can help you achieve this.