Coral Environmental services

Legionella bacteria are widespread in nature, mainly living in natural water systems, however, the conditions are rarely right for people to catch the disease from these sources. Outbreaks of the illness occur from exposure to legionella bacteria growing in purpose built systems where the conditions are such that they encourage growth, e.g. dirt and heat within storage tanks, hot water cylinders, cooling towers, spa pools and hot water systems used in all sorts of premises (work and domestic).

An integral part of the ACOP’s requirements is the need to undertake regular monitoring and checks on the systems to ensure that they are operating within the guideline parameters. By using the information gained during the risk assessment process, Coral can firstly design a bespoke monitoring and testing regime based upon the guideline parameters laid out in ACOP L8. The frequency of inspection and maintenance will depend on the system and the risks it presents. All the inspections and measurements should be recorded. A site specific water hygiene log book can then be instigated which can be used to record and collate all of the information relating to water hygiene. The upkeep of this log book will ensure your total compliance with current legislation and guidance.

In order to control the legionella risk and maintain water hygiene, domestic and cooling water systems including storage tanks, calorifiers, towers and condensers should be inspected regularly and, if necessary, physically cleaned and then disinfected. Disinfection and physical cleaning of domestic water, food processing and evaporative cooling systems is essential if water hygiene is to be maintained and the risk of Legionnaires Disease is to be controlled.

The Approved Code of Practice and Guidance L8 (ACOP L8) states that there are certain steps that you can take to prevent and control the potential threat of Legionnaires’ disease; these include; Avoid the use of materials which harbour bacteria and other micro-organisms. Maintain the cleanliness of the system and the water in it. Control all conditions to avoid the Legionella bacteria spreading and growing. Clean your system to reduce the build-up of sediments that could harbour bacterial growth.

Pre-commission cleaning is achieved through a process of flushing and chemical cleaning (where required) followed by the addition of biocides and inhibitors. Systems designed and cleaned in accordance with BSRIA’s BG 29/2012 guidance are far less likely to experience operating problems. The main contaminants found in both heating and chilled closed loop water systems are installation debris, scale, corrosion products and biological fouling. These cause various different problems but in general, to some degree detrimentally affect the operating efficiency of the system and the life of the system materials.