Many types of industrial equipment can potentially produce an explosive oil mist if a fault develops. This includes almost all equipment in which oil is under pressure, such as hydraulic systems, pressurized lubrication systems, and oil-based heat transfer systems, among others. These are widely used and found in many industries, including service plant rooms and production facilities.
As part of controlling the risk, the Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) require risk-based ‘area classification’ in places where oil mists can be produced. However, information on the conditions under which a mist can ignite and continue to burn is limited.
This report summarises work carried out within the MISTS2 project. MISTS2 followed an earlier Joint Industry Project, MISTS [RR980 (2013), RR1107 (2017), RR1108 (2017), RR1109 (2017), RR1110 (2017), RR1111 (2017)]. Both MISTS and MISTS2 projects were set up to improve understanding of the conditions required for mist ignition and flame propagation. Such understanding is important for assessing the risks in each area where mists could be produced and determining where specific control of the risks is required.
Unlike the MISTS project, which considered more fundamental aspects of mist cloud formation and ignition, MISTS2 focused on situations where simple experimental results could be used directly to give the greatest improvement in understanding of mist explosion safety. The project programme was broken down into three work packages, each of which is more fully described in its own separate Research Report [RR1208, RR1209 & RR1210].
The research was carried out by specialists from HSE’s Buxton laboratory and Cardiff University’s Gas Turbine Research Centre in Port Talbot.