Dr Richard Graveling
Head of Human Sciences
Institute of Occupational Medicine
Heat stress is recognised as a potential problem in many industries including brick-making (kiln work); metal working (steel and precious metals); asbestos clearance and glass-making. The HSE regard the glass industry as a particular risk sector, specifically drawing attention to this in their guidance note on heat stress (GEIS1, 2003). Existing control measures within the industry frequently rely heavily on personal awareness, expecting workers to realise when they are becoming overheated and that they can (and will) withdraw themselves from the risk. However, this makes no allowance for the individual who is temporarily less tolerant (perhaps because of incipient illness) or for an aging workforce (who might not recognise their reducing tolerance). Even where they have previously been found to be effective, good working practice advocates that it should not be assumed that such measures are effective. Measurement of physiological parameters, particularly body temperature, often provides assurance that such systems are effective by demonstrating that potentially dangerous body temperatures are being avoided
In recent years, intra-gastric (IG) temperature (measured through the use of a temperature sensitive radio-pill) has increasingly replaced the use of rectal temperature as the definitive measure of core body temperature. However, practical and financial issues mean that it is not a viable method for routine industrial use. Technological advances mean that new measures, such as the use of infra-red sensors to measure tympanic temperature, theoretically provide a solution for industrial monitoring. Opinions vary as to the reliability of this outside the clinical environment. However, some work by the IOM suggests that many of these problems can be overcome by careful attention to technique; and that it might offer a viable, robust measure.
Against this background, it is proposed to carry out a study to investigate the use of IG temperature in the glass industry as a ‘gold standard’ to validate the routine measurement of tympanic temperature using a hand-held infra-red (IR) device. Measurements would be obtained of IG and IR temperatures on workers in hot conditions to allow statistically robust predictions of the levels of accuracy and reliability obtainable with IR measurement of body temperature. These will be used to provide direct evidence of the effectiveness of existing control measures and to establish a viable, practicable procedure for the routine monitoring of levels of heat strain amongst industrial workers within the industry.
The work would be carried out by a team from the Institute of Occupational Medicine (a leading centre in industrial heat stress) and Optimal Performance Ltd (recognised experts in the use of IG pill technology).
The proposed work has been extensively scrutinised by IOSH who, in recognition of the importance of this work to health and safety, have agreed to provide 50% of the funds needed to carry out this study.