Coventry Academy School – Legionella risk assessment
Acquiesce Environmental Compliance work with a number of schools, colleges and educational facilities in the West Midlands area, as well as further afield in Warwickshire, Staffordshire, Worcestershire & Gloucestershire to provide legionella risk assessment, monitoring services, sampling, remedial plumbing works, TMV servicing and consultancy.
We received an enquiry from a large Coventry based Academy school. The site had various different types of water systems over a number of buildings, including a chlorine dioxide dosing unit fitted on the incoming mains water supply to the site. Records had indicated that the unit was working correctly and chemical levels at sentinel outlets were correct. Acquiesce Environmental Compliance attended site, and found the chemical containers feeding the unit to be dry, and no detection of chemical at any outlets. There was no indication of records of why the unit was first installed. Chlorine dioxide units are often fitted in buildings with water systems that have had history of bacterial issues, such as legionella bacteria present. This is often the last resort when remedial works have been completed, disinfections, sampling and a review of the control scheme has taken place.
Acquiesce Environmental Compliance carried out a thorough legionella risk assessment spending nearly a week on the site, identifying any areas of concern within the systems that could contribute to the growth of legionella bacteria.
Once the report was issued, Acquiesce Environmental Compliance compiled a full list of remedial actions including reducing the volume of stored water in the building by either removing cold water tanks, or reducing the volume of those in place. These were completed in a timely fashion. Backflow prevention devices and fittings that matched the requirements of water regulations to prevent poor quality water (such as heating water, water containing chemical fluid etc) flowing back into the town mains supply.
Temperature issues were quickly addressed, and a sampling regime recommended to identify if the primary method for legionella control, temperature, be used rather than secondary disinfection.
After a 4 month sampling regime, and no positive legionella samples, the chlorine dioxide unit, which was now obsolete was removed. Temperature control is now the primary method of legionella control for the school, paired with an extensive flushing regime to flush all infrequently used outlets and ensure that water is kept moving, even during times of the school being closed to pupils & staff, and throughout the COVID-19 lockdown periods.
