Legionnaires’: Is it time for tougher controls?


A training company has warned industry to react swiftly to the outbreak in Edinburgh of Legionnaires’ disease or risk losing the confidence of the public.
Tony Green, business manager for water systems at Develop Training in Linlithgow, said: “Almost every year there is a large reported outbreak of Legionnaires’ disease which raises awareness of the issue but is there more that could be done before it gets to this stage? What could be done to try and prevent or minimise outbreaks in the future? Should we focus on greater awareness or higher training requirements or even more stringent controls?”
The UK’s most serious outbreak of the disease was in Barrow-in-Furness, Cumbria, in 2002 and was traced to an air conditioning system at a council-run arts complex. Seven people died and there were 180 confirmed cases, but it was estimated 2,500 people might have been affected.
Every year there are around 300 reported cases in England and Wales but figures in Scotland are usually low, between 20 and 40 cases a year, the majority of which are contracted overseas. Newly-published statistics show 34 cases reported to Health Protection Scotland in 2011 against just 16 the year before.
An estimated 10-15% of otherwise healthy people who contract the disease will die. The number of deaths may be higher in people with pre-existing health conditions, such as a weakened immune system.
Green added: “Large buildings, such as hotels, hospitals, museums and office blocks, are more vulnerable to legionella contamination because they have larger, more complex water supply systems in which legionella contamination can quickly spread. So there is a massive potential problem. There are already strict regulations regarding the maintenance and control of water supply systems, such as either keeping the water cooled below 20ºC or heated above 60ºC to prevent an outbreak of Legionnaires’ disease.”
Current training requirements are designed to ensure that systems are maintained to standards that minimise risk and do not harbour the bacteria that cause the disease.
Health & Safety Executive investigations into the Edinburgh outbreak led to improvement notices being served on two businesses – a pharmaceutical company and a distillery – and 16 cooling towers in the south-west of the city being treated with a range of chemicals to kill bacteria.
“Interestingly one of the Edinburgh improvement notices has been served because one firm has allegedly failed to maintain their control measures for the safe operation of the cooling tower to the required standard,” said Green. “It does not indicate an immediate risk from Legionella as this was being controlled by the emergency dosing of chemicals and the company’s subsequent voluntary shutdown of the cooling tower. This is an example of how this particular outbreak has resulted in the HSE discovering other potential issues, even if this is not the actual source.
“It is expected that the Health and Safety Executive will renew its warning to companies to ensure that water storage and cooling systems are adequately treated to prevent the growth of the Legionella bacteria. But we are calling for more to be done.”
He suggested that it could be time for a review of legislation, particularly the Control of Substances Hazardous to Health 1999 which covers safety issues, such as the identification, assessment, prevention or control and management of the risk, plus matters of training and competence and good record keeping.

Image: A number of the city’s cooling towers were treated.