Making an investment in safer water systems

These days we know quite a bit about the bacteria that can cause outbreaks of Legionnaires’ disease, but that doesn’t seem to have made us any better at stopping outbreaks. There are around 300 reported cases in the UK every year, but experts believe the figure is more like 9,000 because it is often misdiagnosed as other forms of pneumonia.

120,000 people are thought to have died in the US since the cause of the disease was established there more than 30 years ago. It was first identified and received its name following an outbreak among delegates at a meeting of the American Legion in a Philadelphia hotel in July 1976.
Around 12 per cent of cases are fatal, but the proportion is much higher among the old and infirm where up to 50 per cent die. That is why it should be such a major concern for those charged with running hospitals and other healthcare facilities.
The risks are increasing and some experts believe the bug is mutating and can, in some instances, survive in water that meets current safe temperature guidelines. It is also showing resistance to some of the chemicals designed to kill it. 

Short sighted
There are also problems with the way in which water systems in care homes, hotels, schools and a host of other establishments are monitored and treated. Reportedly some of the logbooks designed to identify areas at risk, particularly within internal pipework, are not being filled in properly. This is extremely risky and short sighted.

Cuts to building maintenance budgets were among the worst side-effects of the recession and the intense pressure on public sector spending. The whole topic of maintenance is poorly understood by some managers, who often regard it as an optional extra and struggle to understand where it can add value.

It has been widely reported that spending on water treatment designed to guard against the threat of legionella has been cut in hundreds of buildings meaning that the frequency of dosing with chemicals, for example, is reduced to dangerous levels. A risky way to deliver budget cuts, but a risk many seem prepared to take and keep on taking.
Ironically, aside from the health and safety implications, planned and well organised water treatment will also reduce building running costs by improving energy efficiency so managers could actually earn a rapid return on a modest investment. However, that requires a clear understanding of the issues and a willingness to invest for the medium to long-term.

Water systems
The greatest risk from legionella bacteria is found in the hot and cold water systems in buildings where water is delivered as an aerosol or fine spray through taps and shower heads and can, therefore, be inhaled. The bacteria is present in a great many places, it is only once it is airborne that it becomes a threat.
Legionella bacteria also thrive in water temperatures between 20-45 degrees Celsius, but some mutations are thought to be surviving in even higher temperatures – up to 60degC. The bacteria will multiply into large numbers if water is stored at these temperatures.
Hospitals are particularly vulnerable because of the amount of hot water they use and the relative old age of the equipment used to both heat and store it. ‘Dead legs’ in pipework – another common feature of old-fashioned systems – will provide ideal breeding grounds for the bacteria that can then be circulated around the rest of the system when those sections are flushed out.
Poorly maintained cooling towers and air conditioning systems can often be the source of the bacteria, which then proliferates and circulates around the piped water network of the building. There is also evidence of a growing resistance to some of the biocides designed to kill legionella bugs.

Risks are also increasing because many water heating systems are being shut down for periods, or hot water temperatures lowered, to save energy. This means the temperature of the stored water drops into the ‘danger zone’ where the bacteria proliferates.

The increased use of renewables can create problems because these systems generate hot water at lower temperatures than conventional heating. Again, without the proper controls and maintenance, these systems can create the ideal breeding conditions for legionella bacteria.
Rainwater harvesting systems are also becoming more common and they are a particular threat because they store large amounts of water that could already be contaminated.
There is a pressing need for everyone involved in building maintenance and management to understand where the risks lie. In particular, building owners and users and facilities managers must be aware of the increasing dangers posed by the disease, especially to the infirm, and must ensure that adequate steps are taken to control the circumstances in which the legionella bacterium is likely to thrive. Risk assessments are a vital starting point and these must be updated to take new factors into account as technologies and building layouts change.
One additional risk is the fact that, in many places, staff numbers have been reduced to meet budget cuts. The resultant higher workloads on those remaining mean there is more room for human error. For example, monthly temperature checking and manual flushing can be compromised. And even if monthly checks are meticulous, who knows what is happening, day-in-day-out, as temperatures fluctuate within any system?

Continuous dosing
One solution, which is becoming increasingly popular, is ‘continuous dosing’. This is designed to maintain water systems in a permanent state of excellent hygiene at all times. There are a number of dosing systems capable of releasing controlled levels of chemical treatment into the water system at a set times or in response to changing conditions in the water so removing some of the potential for human error or omission. By reducing the labour intensity of the process it can also help hard pressed managers meet their cost cutting obligations, but this time without compromising safety.
Well-planned and resourced water treatment also reduces energy consumption, another saving. For one thing, systems that are continuously maintained do not have to be run at high temperatures in order to guard against legionella build up. A number of buildings run their heating systems all hours of the day and night just to guard against the threat, but that is not necessary if the system is properly treated and monitored.

Continually running heating systems at high temperatures also increases the build-up of scale, which further reduces efficiency and shortens the operating life of expensive heating and hot water equipment. Scale acts as insulation inside pipes and heat exchangers so reducing heat transfer. Each millimetre of limescale reduces energy efficiency by eight per cent.
Also, extremely hot water – a common feature of many hospitals – increases the risk of scalding injuries to patients and staff. Many building owners have had to introduce thermostatic mixing valves at considerable expense to address the problem, but they could save themselves time, trouble and money on a number of fronts if they could maintain water at a more civilised temperature. 
Properly treated systems also suffer from fewer breakdowns, so reducing the need for costly repairs. All in all, a planned and sophisticated maintenance regime for water systems could be one of the best investments a building operator ever makes – both in terms of critical health protection and running costs.
The cost of cutting back on water treatment was demonstrated all too tragically last year at Basildon Hospital in Essex where the resulting outbreak led to two deaths, six seriously ill patients and a £100,000 fine. It appears that managers had ignored warnings from regulators and consultants and reduced their spending on chemical treatment of their water system. Pascal Bates, prosecuting the case for the Health and Safety Executive (HSE), revealed that the hospital cut spending on chemical treatment of the water system in an “inappropriate cost saving measure”.

L8 guidelines
There are of course onerous legal responsibilities on the managers and overseers of buildings charged with preserving the health and wellbeing of occupants. These legal obligations are clearly set out in a single document, published by the Health and Safety Commission (HSC), called Legionnaires’ disease – The control of legionella bacteria in water systems. This is the Code of Practice (ACoP), commonly referred to as L8.
Under L8 it is the building owner’s responsibility to put a proper control strategy in place that includes a system for managing the maintenance of water systems; regular monitoring with the records kept for five years; and training for everyone in the management chain with their skills updated periodically.
L8 is a legal document, so if a building operator does not follow its instructions they leave themselves open to legal action. They are also subject to the legal measures outlined in the Health and Safety at Work Act, which includes wider provision for protecting employees.
Accurate record keeping, corrective action and complete audit trails are essential parts of the guidance. Anyone who thinks these might be sensible things to cut back on to meet short-term budget targets is taking a huge and unnecessary risk.

Further information