An interesting study was recently completed which focused on the heat and heart risks of work emergency & rescue simulations. What this highlighted was that in these situations especially when simulating actual conditions, the physical risks on the body were much more than expected.
The researchers from the Laurentian University Centre for Research in Occupational Safety and Health measured the physiological responses of participants in an international mine rescue simulation competition. During the competition, rescue teams of five were required to descend via vehicle to an underground mine and attend to injured workers, subdue a simulated fire and load an impaling victim for transport to the surface. They wore personal protective equipment weighing 22kg and carried heavy tools and supplies weighing 100kg.
The researchers found nearly half of the study participants had dangerously high heart rates during the two-hour exercise, while more than half had mean core body temperatures of 38.6 degrees or above, well above the normal temperature of 37 degrees. The highest recorded core temperature was 39.88 degrees, which nearly meets the criteria for heat stroke. The competition participants worked for about 2 hours where the only "rest" was walking or kneeling for periods of fewer than 5 minutes, which was an accurate depiction of rescue work.
They suggest research is needed on methods to improve or maximise rescuers' opportunities to rest and hydrate, such as through a rest protocol or using back-up teams to reduce assignment time. The results also highlight the need for comprehensive heat exposure plans. The researchers indicate that previous studies showed that after increases in core temperature, cooling did not begin for about 25 minutes after rescue training ended.
While paramedics are often on hand during exercises, closer attention should be given to all participants immediately after an event; they should be tested for heat strain and monitoring should continue for at least an hour. From a perspective of these type of simulation exercises, researchers suggested that paramedics or doctors should be present at the exit and examine all workers for visible symptoms of heat illness (e.g. excessive sweating, lack of sweating, red skin, complacency, etc) and to make certain they are rehabilitating properly (e.g. drinking plenty of water, resting, etc). What happens however in actual emergencies, what are the risk for our emergency service personnel who complete this work regularly and how well do we monitor the effects of that work on them for their everyday response related tasks, especially in the heat?
The researchers indicated that future research should focus on practices to actively cool rescuers throughout an emergency and immediately upon exit from the mine, which would be beneficial and potentially lifesaving. The researchers recommend a fitness standard and mandatory fitness programs be implemented for mine rescue workers where participation is monitored.
Fitness goals should include targets for aerobic fitness, body fat percentage, core body strength and grip strength. These factors will help workers overcome the risks of a cardiac event during or after the rescue, drive down body heat retention and prevent common injuries. How much do we understand of the presence of these risks in our work where similar arduous conditions may exist- what type of monitoring happens at your workplace or is it essentially managed by incident occurrence?
Konrad, J et al; Effect of a Simulated Mine Rescue on Physiological Variables and Heat Strain of Mine Rescue Workers., J Occ Env Med,