According to statistics from The Home Office, Fire and Rescue services in the UK attended 14,308 fires in non-dwelling buildings in 2020. The effects of fires in the workplace can be devastating, causing injury as well as significant damage to property and the surrounding environment. However, most fires are preventable when employers implement the correct preventative measures. Here Clive Jones, managing director of thermal fluid specialist Global Heat Transfer, outlines the three key steps to managing thermal fluids in accordance with regulations.
Any facility that uses heat transfer systems containing thermal fluid must proactively maintain them to mitigate for potential risks associated with explosive atmospheres in the workplace. These atmospheres can be caused by dangerous substances like flammable gases, mists or vapours, or by combustible dust — if any of these mix with air under atmospheric conditions, they can ignite and cause significant damage.
Thermal fluids are heated to very high temperatures for extended periods of time, so if they are not properly managed, they will begin to degrade. As they degrade, the bindings of hydrocarbon chains will begin to break, causing the flash point, the minimum temperature at which a fluid’s vapours will ignite in the presence of an ignition source, to decrease. If fluid condition continues to deteriorate and the system is not regularly maintained, it can increase the risk of fire.
For example, if degraded fluid is leaking from the system, the hydrocarbons produced during degradation are released as vapours, known as volatile light ends. Leaks can also produce a spray of fine material — the greater the pressure, the higher the risk.
The Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) of 2002 and the Explosive Atmosphere Directive (ATEX 137) are mandatory requirements for minimising safety risks and protecting workers from fire and explosion where flammable or explosive materials are present.
This legislation sets out the legal requirement for thermal fluid systems and representative fluid analysis and requires that employers provide a safe working environment. Employers have a legal obligation to comply with this legislation and maintain documentary evidence.
New thermal fluid does not go from being fit for use to needing replacement overnight, but it will degrade over time and create by-products that reduce the efficiency of the system.
Closely monitoring thermal fluid condition is key to reducing the risk of fire in facilities. Engineers should take a sample when the system is hot, closed and circulating to gain an accurate representation of what is happening inside the system. Engineers can use the analysed samples to monitor flash point temperature, intervening if the temperature lowers.
Installing a remote condition monitoring system alongside regular sampling enables manufacturers to monitor and manage fluid condition more closely. For example, Thermocare® 24/7 Live Condition Monitoring is a cloud-based remote monitoring system that continually monitors fluid condition, sharing real-time data with the cloud. The platform can determine the presence of degradation factors and warn maintenance personnel with an alert to smart devices if it detects anomalies.
Under DSEAR legislation, employers must carry out regular risk assessments of any work activities involving dangerous substances, like thermal fluids, and implement measures to eliminate these risks.
A system audit and survey includes a thermal fluid and system risk assessment to check the condition of different system components like the heaters and pumps, storage and dump tanks and insulation. Auditors will also carry out fluid analysis and check maintenance and training procedures, making any recommendations to improve these areas and ensure compliance.
Staff will have varying degrees of knowledge of heat transfer systems, with some having operated steam versions before and others never having encountered a heat transfer system at all.
Plant managers should ensure that the facility always has members of staff available on site that have been trained in thermal fluid systems and fluid management to ensure site and staff safety. Training should cover the basic system operations, like start-up and shut down procedures. Training should also include a comprehensive list of what maintenance staff should check on a regular basis, including potential leaks, wear and tear, faulty gauges, heat and flow. If manufacturers don’t want to handle the training themselves, they can outsource it to a thermal fluid expert.
Although businesses cannot predict whether fires will occur, they can take preventative measures to minimise risk. Thorough training, site safety procedures and regular thermal fluid analysis ensures that facilities with heat transfer systems have taken all the steps required to comply with DSEAR legislation and make employees feel safe.