Revision of body size criteria in standards - protecting people who work at height
reportposted on 2005-10-31, 17:17 authored by Victoria HainesVictoria Haines, Edward Elton, Michael Hussey
The Ergonomics and Safety Research Institute was commissioned by the Health and Safety Executive to consider whether the body size criteria in standards which are used to test Personal Protective Equipment (PPE) safety needed revision. Currently, the PPE for workers at height is tested using a mass of 100 kg (BS EN 361: 2002), this being the minimum chosen weight to test this equipment. The 100kg mass represents the 95%ile weight of the UK adult population; this weight has also been used to represent the working at height population. However, anecdotal evidence suggests that many people who work at height do not fall within the normal size distribution of UK adults on which the 100 kg was based on. The main aims of this research were to determine the actual weight distribution of individuals who work at height, also to collect basic anthropometric and demographic data, to establish whether the current relevant design standards are sufficient A total of 589 people who worked at height comprised the sample; 15 body measurements as well as demographic data were taken from each participant. Two additional dimensions were calculated (Weight of Equipment and Working Weight), to provide information on how much equipment people were carrying while working at height and to determine the total weight of the worker if they were to fall from height. Clothed Body Mass Index was also calculated for participants. Workers were allocated to one of 10 industry categories for more detailed analysis of the data. The re-sampling technique of bootstrapping was used on these data, as it provides distributions and confidence limits for any statistic. Bootstrapped confidence intervals for the 99th and 95th percentiles are given for Weight and for Working Weight. Results show that the current figure of 100 kg significantly underestimates the actual 95th percentile for workers Weight Without Equipment. It is likely (95% confidence) that the interval 112.3 kg 118.4 kg covers the true value of the 95th percentile for Weight Without Equipment and the interval 116.2 kg 122.0 kg covers the true value of the 95th percentile for Working Weight. Results also suggest that the torso dummy currently specified in BS EN 364: 1993 generally under-represents the size of people who work at height. Data that could be used in the design of a full bodied dummy or safety nets to prevent limb penetrations are presented.