HSE Legionella Water Treatment Contractor Inspection Programme

Published on 05/15/2020 | by Waterline Admin

As featured in waterline Spring 2020

HSE Legionella Water Treatment
Contractor Inspection Programme

By Duncan Smith, HSE

Between 2012 and 2018, HSE undertook a series of proactive interventions to reduce the risks from wet evaporative cooling systems. These interventions were impactful, as the degree of non-compliance reduced over time. However, it was evident that a small number of dutyholders struggled to achieve sustained compliance due to poor or inadequate service provision.
In early 2019, HSE carried out a novel intervention targeting Water Treatment Contractors (WTC). The aim of the intervention was twofold: to raise standards via advice, education and promotion, and also to take enforcement action where it was appropriate to do so (in accordance with HSE’s Enforcement Policy Statement and Enforcement Management Model). HSE recognise raising the standards amongst WTCs should have significant gearing effect and should also assist dutyholders to achieve sustained compliance.

Intelligence from the previous wet evaporative cooling system interventions was used in the targeting of WTCs. Head office visits were undertaken to examine the policies and procedures involved in the planning and delivery of services, as well as on demonstration of competence.
Inspectors used bespoke operational guidance drafted for the intervention. This required Inspectors to probe specific aspects of service provision and also ensuredconsistency of approach.

Main Findings
Of the 24 inspections completed, greater than 1 in 3 WTCs were judged to be in material breach of law and it was necessary for the Inspector to write to the WTC to secure improvement.
By far and away the single biggest issue found was in relation to the adequacy and suitability of respiratory protective equipment (RPE) required for system cleaning when there was a risk of aerosol generation during activities such as jetwashing. Material breaches relating to RPE accounted for more than 1 in 2½ of all the breaches found and these issues were evident at more than 1 in 4 of all WTCs inspected.
Other highlighted concerns related to the Legionella risk assessment process, cleaning techniques and training/competence of staff.
A detailed report on the intervention is being prepared and will be added to the Legionella Webpages on the HSE website soon.

Whilst the results of this intervention do not indicate the need for a larger intervention at this time, however, the quality of WTC service provision should be kept under review by HSE. Existing advice and guidance on RPE for cleaning activities needs to be more prominent and disseminated more widely within the Legionella control industry. Appendix 6 of HSG53 (Respiratory protective equipment at work. A practical guide: www.hse.gov.uk/pubns/priced/hsg53.pdf) advises that a particulate respirator with an assigned protection factor (APF) of 20 would be the minimum acceptable protection level for airborne micro-organisms and that for cooling tower cleaning using high-pressure hoses, a powered respirator with full facepiece or hood/blouse might be the most suitable because of the work rate and wet conditions. Further guidance can also be found in various COSHH Essentials direct guidance sheets:

Product Spotlight

Single Syringe Test Kit

The world’s fastest Legionella test! Get results on site for the strain of legionella that causes practically all legionnaires’ disease cases and outbreaks in only 25 minutes. On site results removes the risks associated with transportation of samples. Simple to use, no specialist training required. Why would you wait days for test results? Contact us at Wycombe Water a Hydrosense distributor.

Neptune Water Safety

Neptune is an enterprise-grade, web-based water safety monitoring system which uses discrete, wireless multi-probe thermocouple devices that are easily attached to water assets in order to help maintain the safety of an organisation’s water system. By continually monitoring and analysing temperatures and flow events over time, Neptune helps identify conditions likely to create harmful bacteria such as Legionella or cause freeze or scald risk, improving safety for building users.

PrimeLab Photometer

The PrimeLab photometer hand-held Bluetooth® device is expandable and portable, developed for ultimate flexibility for use in a range of water systems. With only one light source and the JENCOLOR multi-spectral sensor used exclusively in the PrimeLab, it is possible to measure all water parameters where the water sample is visibly discoloured after addition of a reagent. Key Features of PrimeLab Photometer: The first and only PrimeLab photometer with just 1 LED / 1 JENCOLOR sensor, covering the 400 wavelength (380nm-780nm). More than a 100 different parameters available. Activation of add-on parameters is possible even after purchase. Powerful PC-software and app with free cloud service. Creating reports and dosage recommendations by just a click, using your individual water treatment chemicals.

Huwa-San TR-50 Silver Stabilised Hydrogen Peroxide

Huwa-San TR-50 is a commercial water disinfectant and biocide designed for shock disinfection or constant dosing. Huwa-San TR-50 kills legionella bacteria and in addition removes biofilm. It is safer to use than chlorine as the disinfection breakdown products are oxygen and water. Independent testing shows that Huwa-San TR-50 provides a very wide spectrum of biocidal activity against bacteria, viruses, spores, fungi, amoebae (such as amoeba acanthus which can act as a host to legionella bacteria) and algae. Use disinfectants safely. Always read the label and product information before use.

MC1+ Protector

Formulated to prevent wear and tear and the resulting debris, MC1+ stops magnetite and other deposits forming. As it does this, it protects the central heating, keeping the boiler working efficiently and helping to ensure the system lasts for longer.

MM2050 - PT100 Thermometer

Four/three/two wire measurement, Max/min functions, Hold function, Dual display, °C/°F/°A selectable, Simultaneous display of real time and max/min/hold measurement, Self calibrating.

MD610 Photometer

The MD610 gives you a mobile device in a modern design with the analytical features of a laboratory photometer. All important water analysis parameters from A(luminium) to Z(inc) are covered. Combined with the high precision of Lovibond® reagents, a reliable and quick analysis of water samples is guaranteed. Reagent tablets, powder reagents, liquid reagents, or cuvette tests are used depending on the method.

Armitage Shanks Markwik 21


(TB H2a) an integral thermostatic bib mixer tap, single long lever mixer. Single flow fixed horizontal nozzle, sequential operation. Sequential operation ensures both hot and cold supply are purged on each use, long lever gives precise control. Insulated technology keeps the ‘hot’ side of the mixer at a safe surface temperature.

AS Shower chrome

AS Shower chrome

Legionnaires‘ disease is usually spread by the breathing in of water vapour containing Legionella bacteria which is then deposited on the lungs. The bacteria thrives in water temperatures between 25 and 45°C and so showers by their very nature create an ideal environment for the bacteria to spread. The AS SHOWER chrome filter provides reliable and immediate protection against Legionella, removing bacteria at the point of use, allowing users to shower safely.