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RR836 - Perception and understanding of how local exhaust ventilation (LEV) works and how effective it is: Phase 2

Background: Health and Safety Executive (HSE) inspectors had anecdotal evidence that employers and employees had misperceptions and overconfidence in LEV systems. Therefore, HSE commissioned the Health and Safety Laboratory (HSL) to gain insight into these users' current understanding and perceptions relating to different types of LEV systems as well as compare and contrast the results of these two groups.

Methodology: A HSL researcher devised a bespoke methodology using a qualitative approach that consisted of semi-structured questionnaires, a series of 2D line drawings and cut-out LEV hood pictures. These were applied together in face-to-face interviews with a purposive sample of employers and employees from the manufacturing sector who owned/used LEV systems within the UK.

Results: Participants had an adequate understanding of the basic principles of LEV systems. However, many had limited training on LEV and most of their information came from manufacturers, suppliers and installers. There were many misperceptions and overconfidence in the use and effectiveness of LEV that were found specifically in relation to the capture zone (area of air suction around the hood).

Conclusion: Although employers and employees knew the basics of LEV use and operation there was a cluster of misperceptions and overconfidence in relation to the interpretation of the capture zone. Therefore, the results could be used by HSE as part of its wider communication strategy and in order to dispel misperceptions and overconfidence amongst employers and employees perhaps by showing them how a capture zone works and how contaminants interact with it.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the author alone and do not necessarily reflect HSE policy.

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Updated 2021-04-23