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Exposure Assessment & Control                      July 2018

Effect of hood size on a qualitative fit test

Presentation on the effect of
hood size on a qualitative fit test

Alison Bowry from HSL’s occupational hygiene team gave a presentation on hood size effects on 25 April 2018 at the ISRP European Section Spring Seminar and AGM.  


RPE can't protect the wearer if it leaks. A major cause of leakage is poor fit.  Fit testing will ensure that the equipment selected is suitable for the wearer.  One such method of fit testing is the qualitative fit test method.


A qualitative fit test (QLFT) kit comprises a hood, which is worn over the head during the test, sensitivity and fit test solutions and two nebulisers. It has been observed that the range of hoods varies in construction, shape and size, and therefore in volume.  HSE282/28 (HSE, 2012) specifies the dimensions of the hood that was used in the validation testing of the qualitative taste method. 


Concerns have been raised whether hoods with larger volumes are having an effect on the concentration of the aerosol in the hood space, and therefore possibly also having a bearing on the quality and consistency of taste-based QLFT fit test results.


To investigate whether there was cause for concern, a sample of the range of hoods from the UK market was obtained, their volumes were measured and a series of preliminary aerosol concentration tests were conducted.  Results showed a general trend in the reduction of the number and mass of particles per unit volume with increasing hood space volume. 


Click here for further information on the RPE services offered by HSL.  

Exposure to Crystalline Silica Dust

Dr Steve Forman speaks about exposure to crystalline silica dust at the SOM/FOM's 2018 conference

The Health and Safety Executive (HSE) has urged organisations to review their health surveillance programmes for workers who have a high risk of developing respiratory diseases to ensure that screening is sufficient. 


Speaking to the Society and Faculty of Occupational Medicine’s annual scientific conference this week, Dr Steve Forman, HSE's Principal Medical Adviser, said workers who are exposed to, or at risk of exposure to, crystalline silica dust should regularly undergo both x-ray screenings and lung function tests – not one or the other.  


Read the full article here.


More on respiratory crystalline silica from HSE's Dr Liz Leese...

Also on the topic of respiratory crystalline silica, Dr Liz Leese of the Biological Monitoring team gave a presentation at the 19th Biennial National Atomic Spectroscopy Symposium (BNASS) on some novel research that HSE have done looking at silica particles in exhaled breath condensate. 

This technique could improve exposure assessment and worker awareness in the future.  The preliminary findings have been published.

Training courses

LEV - Practical Management of Local Exhaust Ventilation Controls  - 31 July 2018

RPE Essentials – 25-26 September 2018

RPE Fit Test – Introduction – 27 September 2018

Management of Hand Arm Vibration in the Workplace - An Introduction – 3 October 2018

Biosafety - concepts and working practices at Containment Level 3 – 8-12 October 2018

Hand-Arm Vibration Syndrome (HAVS) Refresher – 17 October 2018


A full list of available training is available on HSL’s website here.