The danger of carbon monoxide is high in the public consciousness after the Thomas Cook court case. But the risks of the 'silent killer' at work are often overlooked, warns Dominic Slingsby.
1 July 2015 | By Dominic Slingsby
Carbon monoxide (CO) is a colourless, odourless, tasteless and poisonous gas that is produced when faulty boilers, generators and other combustible appliances fail to properly burn carbon-based fuels including gas, coal, oil and wood.
But it's an issue that's often overlooked at work, despite most workplaces having a boiler and a whole host of other fuel-burning appliances.
Carbon monoxide alarms are cheap, easy to install and immediately sound an alarm if carbon monoxide is detected in the atmosphere.
Whereas there are specific legislation and Building Regulations relating to smoke and fire alarms, the regulations surrounding CO poisoning vary and predominantly focus on homes and the domestic market. But even where Building Regulations require CO alarms to be installed near heating appliances cookers are excluded, so legislation surrounding their use is far from straightforward.
CO is difficult to detect because often people don't realise they're breathing it in until it's too late, which is why it's often described as the 'silent killer'.
And although many people consider the dangers associated with CO at home, where detectors are becoming increasingly common, many don't give it a second thought in the workplace.
Inhaling CO prevents the blood from carrying oxygen around the body and although early symptoms of CO poisoning vary from person to person, they can often be confused with food poisoning, viral infections and flu. Headaches, dizziness, breathlessness, nausea, chest pains and tiredness are all common side effects and anyone exposed for a long period of time can fall unconscious and even die.
Another indicator that CO is present at work is if the symptoms ease when you go home, but then return the following day when you're back at work.
This often becomes even more noticeable when you have an extended break from work. More than one person experiencing similar symptoms is another telltale sign.
If workers are experiencing these types of symptoms the workplace's health and safety manager should be informed. He is then obliged to carry out a thorough investigation.
If CO is found to be present, employers must take action to fix the problem and greatly reduce the possibility of further exposure to it.
The main causes of carbon monoxide poisoning in the workplace are poorly maintained and defective appliances combined with inadequate ventilation. Warning signs that indicate combustion problems in appliances can include flames burning orange rather than blue, soot or brown staining and pilot lights regularly going out.
A huge range of malfunctioning appliances can typically produce CO, including boilers, water heaters, stoves, ovens, heaters, clothes dryers, furnaces and generators.
A thorough risk assessment should therefore be carried out on all relevant equipment and appliances that take into account its location, use, ventilation and service schedule.
Many commercial and industrial premises have legal obligations to get boilers and other appliances or equipment serviced regularly. But even where there isn't a definite requirement all boilers and fuel burning appliances should be serviced at least once a year to minimise the dangers.
Often with fixed appliances, problems occur as a result of poor vents and exhaust outlets. These need to be checked regularly for obstructions to ensure that gases can escape.
Similarly, with shared flues in commercial buildings, it's possible for CO to be produced in one area of a building before being transported through the ventilation system and then leaking into another part of the building. And in commercial premises it may be necessary to monitor CO that is generated in indoor parking areas caused by exhaust fumes.
As buildings become more sustainable and environmentally friendly, the risks associated with CO are also increasing. Improved installation, triple-glazed windows and the trend towards making buildings airtight all reduce the scope for air intake, which means that good ventilation systems are even more important.
Ideally, CO detectors should be installed in any areas that contain a fuel-burning appliance, or just outside boiler rooms so the alarm can be heard. In areas with combustion appliances, CO will usually rise until it cools, so it can make sense to position alarms up high. If the number of alarms is limited, priority should be given to any areas that contain a flueless or open-flued appliance or areas that are most frequently occupied. It is also good practice to install alarms in areas with extended or concealed flues passing through them.
Dominic Slingsby is managing director of workplace equipment supplier Slingsby