Legionella Overview

Preventing Legionnaires’ Disease In Emergency Showers and Safety Eyewash Equipment

As part of the routine management and maintenance of safety showers and emergency eyewash equipment, it’s imperative that steps are taken to minimise the risk of legionella bacteria growing within the system. The presence of this bacteria puts users at risk of contracting a number of respiratory infections. In particular, this group of infections includes Legionnaires’ Disease, a potentially fatal form of pneumonia.

The primary function of emergency showers and eyewash stations is to mitigate potential harm from exposure to hazardous chemicals and similar dangers. As such, while it’s important to minimise the risk of contracting legionellosis, this objective should not stand in the way of providing adequate protections against other hazards. It is important to remember that every situation is unique, so you must always consider the specific equipment being used, and the details of any risk assessments already in place.

What are the Risks.

Legionella thrives in warm water, particularly where there are contaminants to accelerate its growth. Typically, infection occurs when contaminated water is inhaled, making drench showers, where aerosols are likely to form, a particular concern.

Other conditions which amplify the risk of legionella growth include the following:

Areas where water is stagnant, or that experience low flow, as this allows the bacteria to grow undisturbed. As the very nature of emergency equipment means it may go unused for prolonged periods, this is a significant risk factor in the management of legionella in these systems.

Temperatures between 20°C and 45°C, as this provides a comfortable environment in which the bacteria can develop. Deposits such as sediment, sludge, or biofilms, which can act as nutrients for the bacteria, and provide a more stable and protective environment for its growth. Corrosion or scale anywhere in the system. This is a particularly important factor, as iron is an essential nutrient for legionella bacteria.

Cleaning, Testing, and Maintenance Procedures

According to HSE guidelines, set out in their approved code of practice for legionella control, you should aim to purge and flush through any eyewash solutions and emergency showers, at least once every six months. However, you should do so more frequently if this is suggested by your risk assessment findings or manufacturer’s recommendations.

All systems used less frequently than once a week should also be flushed weekly, to maintain optimal performance, and to check that they are still functioning correctly and is recommended that you flush to flows stipulated in ANSI Z386.1 and EN15154. Safety shower test kits are available from from Modern Plant.

You should also conduct a thorough inspection of any water tanks once a month, and full cleaning and disinfection of all tanks and components at least quarterly. Setting up a dedicated schedule for these operations is essential, as you will need to ensure alternative emergency facilities are available while those being cleaned or tested are out of action.

Finally, in order to remain compliant with government guidelines, employers with five or more staff are also required to keep records of their testing and maintenance operations, as well as any significant findings of their risk assessments. Details of any tests, checks, or monitoring inspections should be recorded with dates, and kept for at least five years.

Preparing for Every Eventuality

While these steps should greatly reduce the risk of microbial growth in your emergency showers and eyewash equipment, it’s important to be prepared in case any form of legionellosis is contracted. It’s also worth remembering that legionella is not the only microbial hazard that may develop in your water supply.

Symptoms of legionellosis can take up to two weeks to become apparent, due to the incubation period of the bacteria. If there’s any suspicion that you or anyone else has been infected by legionella, it’s essential to seek medical attention immediately. Furthermore, if such an infection is detected, any water sources used by the affected individual must be isolated for immediate cleaning and testing.

Nevertheless, while this is a serious concern, by taking the steps described above, and keeping accurate records of these procedures, you can significantly reduce the risk associated with legionella in your emergency showers and eyewash equipment.