Legionella is a type of bacteria that is naturally found in freshwater environments such as lakes, rivers, and reservoirs. While generally harmless to wildlife in these settings, it can pose a serious health risk to humans when it grows in man-made water systems and is spread through contaminated droplets.
In this blog post, we will explore the risks of Legionella, common sources of the bacteria in the workplace, legal responsibilities for prevention, and how our expert service can keep businesses safe and compliant.
Why Legionella bacteria poses a serious risk: Legionnaires’ disease
Legionnaires’ disease is a severe, life-threatening lung infection caused by Legionella bacteria.
It is contracted by inhaling tiny water droplets containing the bacteria, which can be found in contaminated water systems such as cooling towers, air conditioning units, hot tubs, and plumbing systems.
Symptoms of Legionnaires’ disease usually develop within 2 to 10 days after exposure. Early signs include fever, chills, muscle aches, and headaches.
As the infection progresses, individuals may experience a persistent cough (which can produce mucus or blood), shortness of breath, chest pain, nausea, diarrhoea, and confusion. In severe cases, the disease can lead to complications such as respiratory failure, septic shock, and organ failure.
Certain groups of people are more vulnerable to Legionnaires’ disease. Older adults, particularly those over 50, are at higher risk, as well as smokers and individuals with chronic lung conditions.
Those with weakened immune systems, including people undergoing chemotherapy, diabetics, and those with chronic illnesses, are also more susceptible to severe infections.
The severity of Legionnaires’ disease varies. The fatality rate is around 10%, but this increases with hospital-acquired infections. Early diagnosis and antibiotic treatment are critical for reducing the risk of serious complications and improving recovery outcomes.
Infrequently used taps are more likely to house legionella bacteria due to ideal bacterial growth conditions.Common sources of Legionella in workplace water systems
Several workplace water systems can become breeding grounds for Legionella if they provide the right conditions for growth. These include:
Hot and cold water systems
A plumbing system that supplies hot and cold water to a building can provide the perfect environment for Legionella to develop if not properly maintained.
These systems often include complex pipe networks, water storage tanks, and areas where water can sit for long periods of time, providing ideal conditions for bacterial growth.
Legionella thrives when water temperatures range between 20°C and 45°C, particularly in sections of the system where water stagnates due to infrequent use, poorly designed pipework, or dead-end pipes. Stagnant water allows disinfectant levels, such as chlorine, to drop, reducing the system’s ability to prevent the development of the bacteria.
Proper water monitoring and control measures are required to prevent bacterial growth and reduce the risk of exposure in the workplace.
Showers and taps
Infrequently used showers and taps allow water to stagnate in the system for long periods.
Stagnant water not only reduces disinfectant levels but also increases the likelihood of Legionella bacteria multiplying, making exposure more dangerous when the water supply is eventually used again.
When shower and tap outlets are used, they release tiny water droplets (aerosols) into the air. If contaminated with Legionella, these droplets can quickly spread and infect building occupants.
Regular flushing and maintenance of these outlets are essential for businesses to prevent bacterial proliferation.
Decorative fountains and water features
Water features, such as ornamental fountains, decorative ponds, and indoor waterfalls, can become sources of Legionella if not properly maintained.
These systems produce mist or fine water spray, which can carry bacteria into the air and be inhaled. If the water is not regularly treated with appropriate biocides or disinfectants, bacteria will multiply.
Routine cleaning, water circulation, and chemical treatment are essential for preventing contamination.
Hot tubs and spas
Hot tubs and spas provide the perfect environment for Legionella growth due to their consistently warm temperatures, typically maintained between 30°C and 40°C, which is well within the ideal range for bacterial growth.
These systems accumulate organic matter such as skin cells, body oils, and cosmetic residues, which can serve as a nutrient source for Legionella.
Since these systems are frequently used in enclosed spaces, such as indoor spas or leisure facilities, the risk of Legionella exposure is even higher.
Regular cleaning, effective disinfection with chlorine or bromine, and proper filtration to remove contaminants are essential to preventing contamination.
“Non-compliance with Legionella control measures can result in formal enforcement actions, such as substantial fines and even prosecution.”
Legal obligations for Legionella control
Businesses in the UK are legally required to assess and control the risk of Legionella in their water systems.
UK regulations, including the Health and Safety at Work Act 1974 and the Approved Code of Practice (ACoP) L8, outline strict requirements for identifying, managing and monitoring these risks.
We have outlined the legal responsibilities businesses must meet to ensure safe water management and regulatory compliance below.
The importance of a Legionella risk assessment
A Legionella risk assessment is an important first step towards effectively managing the risk of Legionnaires’ disease.
These assessments include a thorough evaluation of water systems to identify potential sources of Legionella growth, examine the level of risk, and determine the necessary control measures to prevent it.
Employers are legally required to conduct Legionella risk assessments to protect employees, visitors, and the general public from exposure.
They should be carried out by a competent person with the knowledge and expertise to identify risks and recommend appropriate actions.
Regular assessments are essential and should be conducted at least every two years. However, they must also be carried out whenever there are significant changes to the water system, building use, or occupancy levels, as these factors can directly impact the risk of Legionella.
The need for a written control scheme and regular monitoring
To effectively manage Legionella risks, businesses must establish a comprehensive written control scheme. This document serves as a structured plan for controlling and managing risks while ensuring compliance with legal requirements.
It should outline key measures such as water treatment processes, temperature monitoring protocols, routine system maintenance, and the specific roles of key personnel involved in risk management.
Regular monitoring is necessary to verify that control measures remain effective. This includes regular temperature checks, water sampling, and thorough cleaning and disinfection procedures.
Record-keeping requirements
Employers must keep accurate and detailed records of their Legionella risk assessments, ongoing monitoring activities, and any corrective actions taken to address identified risks.
These records provide critical evidence of compliance with health and safety regulations, demonstrating a proactive approach to risk management.
Documentation should include details of water system inspections, temperature monitoring results, water sampling data, cleaning and disinfection schedules, and any maintenance or remedial actions carried out.
Records must be kept for a minimum of five years to ensure businesses can provide proof of compliance if requested by HSE.
Consequences of non-compliance
Failure to comply with Legionella regulations can have severe consequences for businesses.
Noncompliance with Legionella control measures can result in formal enforcement actions, such as substantial fines and even prosecution.
In a recent case, Sanctuary Housing Association, a sheltered accommodation, located in Birkenhead were fined £900,000 for breaching Legionella regulations.
An HSE investigation into the incident, which occurred in 2018, revealed they inadequately managed the risks of Legionella, provided insufficient employee training, and gave misleading communications to residents about water safety, leading to this huge financial penalty.
Beyond legal repercussions, a Legionella outbreak can severely damage a business’s reputation, leading to a loss of customer trust, negative media coverage, and financial losses.
Public scrutiny and legal action can undermine an organisation’s credibility, making compliance and proactive risk management critical to maintaining a responsible and trustworthy operation.
Preventing Legionella in your workplace water systems
Employers and employees share responsibility for preventing the risk of Legionella in the workplace.
Employers have a duty to follow the legal compliance mentioned throughout the section above. They should also provide employees with clear information and training so that they understand the risks and how to prevent Legionella growth.
Employees are expected to remain vigilant and report any concerns related to water quality, such as unusual odours, discolouration, or stagnant water in workplace systems. Reporting maintenance issues, such as malfunctioning taps, showers, or heating systems, is encouraged to help prevent conditions that encourage bacterial growth.
Employees should also report any symptoms of illness that could be caused by Legionella exposure, such as persistent coughing, fever, or difficulty breathing.
Where necessary, employers should engage professional Legionella control services to test and treat water systems and conduct regular Legionella assessments, helping them stay compliant with health and safety regulations.
How ClearFlow Water Treatment can help
At ClearFlow Water Treatment, we specialise in comprehensive water treatment solutions designed to help businesses manage and control the risk of Legionella effectively.
Our expert team offers a range of services that align with legal requirements and best practices, ensuring your workplace remains safe and compliant.
We offer detailed Legionella risk assessments, tailored water treatment solutions, and professional cleaning and disinfection of water systems. To maintain ongoing compliance, we also provide routine monitoring, temperature checks, and water sampling.
As well as this, our employee training services equip your team with the knowledge they need to maintain safe and hygienic water systems.
Get in touch today to find out how we can help you prevent the spread of Legionella bacteria in your workplace.
