8 legionella risk assessment companies for UK workplaces in 2026

Before you compare quotes, check two things: that the company is registered with the Legionella Control Association for the kinds of water system you have, and that its assessment comes with an up-to-date schematic and a written control scheme. Then shortlist by fit. Legionella Control International suits complex and healthcare systems and keeps its advice apart from treatment work. Goodwater and Swiftclean can assess your systems and then carry out the remedial work. Vectair Environmental works across multi-site portfolios, Water Logic Works and Aqua Legion UK cover London and the South East, and Arinite and Opus Safety handle legionella as part of wider health and safety support.

Whoever you appoint, the duty to control the risk stays with you.

What the law asks of you

In England, Wales and Scotland, regulation 6 of the Control of Substances Hazardous to Health Regulations 2002 requires an employer to make a suitable and sufficient assessment of the risk to health before carrying out work that could expose employees to a hazardous substance, and HSE applies it to bacteria such as legionella. In Great Britain, HSE says the duties in the Health and Safety at Work etc. Act 1974 extend to legionella risks arising from work. In Northern Ireland, the assessment duty sits in regulation 6 of the Control of Substances Hazardous to Health Regulations (Northern Ireland) 2003.

In Great Britain, the standard your assessment is judged against is HSE's Approved Code of Practice L8, fourth edition. If you are prosecuted and it is proved you did not follow it, you have to show you complied with the law some other way. L8 requires whoever carries out the assessment, and advises on preventing and controlling exposure, to be competent to do so, and it requires no particular qualification or accreditation. The technical detail sits in HSG274, HSE's guidance in three parts: evaporative cooling systems, hot and cold water systems, and other risk systems.

How to check a legionella risk assessment company

HSE's guidance on managing legionella risk says to be satisfied a contractor can do the work to the standard you require before you employ them, and it points to a Code of Conduct for service providers and to a British Standard for legionella risk assessment.

The Legionella Control Association register. The LCA is a voluntary, not-for-profit body founded in 1999. Its members commit to a Code of Conduct for service providers and re-register every year, and the LCA runs a programme of company audits by its own assessors. L8 says the Code has no legal status, and its guidance points dutyholders to it as an illustration of the service they should expect.

Registration is by category. The LCA directory shows which risk assessments each member is registered for (hot and cold water systems, evaporative cooling systems, process and other systems, and healthcare), the regions it covers and its registration number, and the LCA says a membership is active while its listing is visible. If you have a cooling tower or an evaporative condenser, check the company is registered for evaporative cooling systems.

The British Standard. BS 8580-1:2019 is BSI's code of practice for legionella risk assessments, aligned with the fourth edition of L8 and with HSG274. Ask whether the assessment will follow it.

The schematic. HSE's review checklist asks whether your risk assessment includes an up-to-date schematic showing the whole system, parts out of use included, and L8 expects one for complex systems. A quote that leaves the schematic out is pricing a different piece of work.

How this list was put together

Apart from Opus Safety, every company below appeared in web search results for UK legionella risk assessment companies that we ran on 19 October 2026. Each offers legionella risk assessments for workplaces, works beyond a single town, and says on its website or its LCA listing that its assessments follow L8 or BS 8580-1. We read each company's website and checked it against the LCA directory the same day, and left out directories, a self-published "top 10" list and companies whose pages gave little beyond a list of services. The numbering carries no ranking.

Opus Safety is on the list, and we wrote it, so read it with that conflict in mind. We have placed ourselves last and said where another company is the better choice. We did not commission assessments from any of these companies, and we have left out their prices, review scores, client numbers and claims about individual staff qualifications. Where a company states an accreditation, we report it as stated, so confirm it with the accrediting body before you sign.

The eight at a glance

Company	Based in	Coverage it states	LCA registration, checked 3 November 2026	Risk assessment categories on its LCA listing	Treatment or remedial work
Legionella Control International	Offices in London, the North West and Glasgow	All UK regions, and abroad	Yes, 2007/1721	Hot and cold, evaporative cooling, process and other, healthcare	No ongoing treatment work, per its LCA listing
Goodwater	Wokingham, Berkshire	Businesses across the UK	Yes, 2001/142	Hot and cold, evaporative cooling, process and other, healthcare	Yes
Swiftclean	Southend-on-Sea, Essex	Nationwide	Yes, 2001/1284	Hot and cold, process and other, healthcare	Yes
Vectair Environmental	Aldermaston, Berkshire	Across the UK	Yes, 2013/2281	Hot and cold, healthcare	Maintenance, cleaning and disinfection
Water Logic Works	Kent	Kent, London and the South East	Yes, 2016/2294	Hot and cold, process and other	Cleaning and disinfection
Aqua Legion UK	London	London and surrounding counties	Not in the directory	Not registered	None in house; oversees your contractor
Arinite	London	The UK and other countries	Not in the directory	Not registered	Not listed
Opus Safety	Birmingham	Across the UK	Not in the directory	Not registered	Not listed

1. Legionella Control International, for complex sites and independent advice

Legionella Control International was founded in 2005 and works from UK offices in London, the North West and Glasgow, covering every UK region and clients abroad. Besides risk assessments, it provides Authorising Engineer (water) services, water sampling with in-field and laboratory testing, compliance audits and City & Guilds accredited legionella training.

Its LCA listing describes it as predominantly a training and consultancy company that does not deliver ongoing physical water treatment or water hygiene work. The same listing covers all four risk assessment categories, evaporative cooling systems and healthcare among them.

Consider them if your site has a cooling tower, a complex hot and cold water system or a healthcare setting, or you want the people advising you kept apart from the treatment contract.

2. Goodwater, for the assessment and the treatment work from one specialist

Goodwater is a water treatment and water hygiene company in Wokingham, established in 1988, which works for businesses across the UK. It states that it is a UKAS-accredited inspection body, number 9714, under BS EN ISO/IEC 17020:2012 for legionella risk assessment of hot and cold water systems, carried out to BS 8580-1:2019. Its assessments include a site survey and schematic drawings.

Once the assessment is done it offers TMV servicing, temperature monitoring, laboratory sampling, tank and cooling tower cleaning and disinfection, dead leg removal and pipework changes, plus dosing equipment and treatment chemicals. It is LCA-registered for all four risk assessment categories, and for water treatment and for cleaning and disinfection.

Choose them if you want one company to assess your water systems and then carry out the treatment and remedial work, cooling towers included.

3. Swiftclean, for water hygiene alongside ventilation and kitchen extract work

Swiftclean, a building hygiene contractor in Southend-on-Sea, runs legionella services from risk assessment and testing to remedial plumbing, TMV testing, water tank cleaning and water treatment. The same company cleans ductwork and kitchen extract systems and tests fire dampers.

It says it works nationwide through locally based teams of directly employed staff, and that its risk assessments and control schemes follow L8 and BSRIA and CIBSE guidance. After the assessment it supplies legionella control log books and can train your own staff. Swiftclean is LCA-registered and says its work follows the LCA Code of Conduct.

Worth a look if one contractor for water and air hygiene across your buildings would simplify your maintenance contracts.

4. Vectair Environmental, for multi-site portfolios

Vectair Environmental, in Aldermaston, Berkshire, carries out legionella risk assessments across the UK and says it can deliver them consistently across multi-site portfolios, with centralised reporting. Its assessments follow ACOP L8 and cover hot and cold water systems, wet air handling systems, cold water storage tanks, calorifiers and hot water cylinders.

Each assessment includes schematic diagrams, an asset schedule and temperature measurements, and where sampling applies, the samples go to a UKAS-accredited laboratory. Vectair offers water system maintenance and monitoring too, plus indoor air quality and ventilation services. Its LCA registration covers hot and cold water and healthcare risk assessment.

A good fit if you run several similar sites and want each one assessed and reported the same way.

5. Water Logic Works, for Kent, London and the South East

From its base in Kent, Water Logic Works assesses hot and cold water systems across Kent, London and the South East, to ACOP L8, HSG274 Parts 2 and 3 and BS 8580-1:2019. Its assessments include an asset list and a basic schematic marking dead legs, blind ends and infrequently used outlets, followed by a control measures scheme and a remedial action summary.

It also offers legionella sampling with laboratory analysis, disinfection and cleaning, and legionella training. It has been an LCA member since 2016.

They suit you if your sites are in that part of the country and you want a regional water hygiene specialist.

6. Aqua Legion UK, for an independent assessor in London

Aqua Legion UK is a legionella consultancy working across London and its surrounding counties. It carries out risk assessments to ACOP L8, HSG274 and BS 8580, and offers routine temperature monitoring, audits and training. Its own consultants or technicians collect every water sample on site.

The company states that it supplies no water treatment, chemicals or remedial works in house. Where work is needed, it offers to oversee your approved contractor, or one it introduces, while the work is done. It is not in the LCA directory.

Pick them if you are in London and want your assessor to have no stake in the remedial work.

7. Arinite, for legionella inside an outsourced health and safety contract

Arinite, a health and safety consultancy headquartered in London, offers legionella compliance as a standalone service or within an outsourced health and safety package: a risk assessment to ACOP L8 and HSG274 with a risk register and a prioritised action plan, a written scheme of control, and either training for your own responsible person or an Arinite consultant acting as your appointed competent person.

Records are kept in its health and safety software, which sends reminders for monitoring, testing and reviews, and it arranges accredited laboratory testing when it is needed. It is not in the LCA directory.

Consider them if you want the consultancy that runs the rest of your health and safety to take on legionella as well, with the records held in its software.

8. Opus Safety, for sites where legionella sits alongside the rest of your health and safety

Our legionella risk assessments are made against ACOP L8, with the technical detail following HSG274. You receive the risk assessment and a written control scheme naming who does what.

We assess legionella risk for builders merchants, warehousing and logistics, manufacturing and engineering and garden centres, among others, where the systems include yard wash-down, quench tanks, process water and plant-display misting. You can book a one-off assessment or include it in the Opus Safety Partnership, and our legionella awareness course covers the risks, the legal duties and the controls for the people running your control scheme, at your premises.

Consider us if legionella is one item on a longer health and safety list for the same sites. Look elsewhere if you want the assessment, sampling, water treatment and remedial work from one company: Goodwater and Swiftclean both list all four. We are not in the LCA directory, so if your contract requires LCA registration, start with the five registered companies above. And if your systems are simple, stable and already well monitored, your own team may be able to keep the assessment under review, and we will tell you so.

How to decide between them

Five questions separate companies that look alike on paper.

Question	What it tells you
Which LCA risk assessment categories is the company registered for?	Whether its registration matches your systems. A cooling tower or evaporative condenser needs the evaporative cooling category
Will the assessment include an up-to-date schematic of the whole system?	Whether the price covers the survey work HSE's checklist asks about
Will the report end with a written control scheme and a named responsible person?	Whether your team can act on it the day it arrives
Does the company also sell treatment or remedial work, and will that be quoted separately?	Whether the recommendation and the sale come from the same place
For several sites, will each be assessed and reported the same way?	Whether you can compare sites and track actions across the estate

Frequently asked questions

Does a legionella risk assessment company have to be LCA registered? No. L8 requires whoever carries out your assessment to be competent, and LCA registration is voluntary. It shows a company has signed up to the Code of Conduct and is audited against it for the categories on its listing. HSE's review checklist names experience, qualifications, training and membership of a professional organisation or recognised trade body as ways to check a contractor's competence.

Can I carry out my own legionella risk assessment? Yes, if you are competent to do it. HSE says you may be competent to carry out the assessment yourself, and that otherwise you should call on a competent person from inside your organisation or outside it, for example a consultancy.

How much does a legionella risk assessment cost? The price follows the number and type of water systems, the size of the site, whether a usable schematic already exists and how many sites are assessed together. Ask two or three companies to quote on the same scope, schematic and written control scheme included. A water sampling visit is a different service: it tells you about one outlet on one day.

How often should a legionella risk assessment be reviewed? L8 sets no fixed interval. It requires a regular review, and a review whenever there is reason to believe the assessment may no longer be valid, for example after a change to the water system or its use, a change of key personnel, or checks showing the controls are no longer effective.

Should the company that assesses the risk also do the remedial work? It can. L8's guidance says anyone supplying water treatment or maintenance services should tell you about deficiencies in your system and about limitations in their own expertise, products or services. If one company will both assess and fix, ask for the remedial work to be quoted separately. Legionella Control International and Aqua Legion UK both say they do not deliver treatment work themselves.

Who is responsible if the assessor gets it wrong? You remain the dutyholder. L8's guidance says employing contractors or consultants does not absolve the dutyholder of responsibility for making sure control procedures are carried out to the standard required, and that you should make reasonable enquiries about a contractor's competence before you sign.

Talk to us

If your legionella risk assessment is part of wider health and safety support for your sites, tell us about your sites and water systems and we will tell you whether we are the right fit.