Asbestos and Other Fibres M504 (replaces W504 OHTA course)

This examination aims to enhance your knowledge of occupational hygiene practice concerning fibrous dusts. The module concentrates on asbestos, but other fibres, e.g. machine made mineral fibres, aramids, carbon, etc., which are increasingly finding uses in industry are also covered.

Who is it for?

Successful completion of this examination will benefit those working in asbestos consultancy as well as in mainstream occupational hygiene, giving an understanding of the health risks associated with asbestos and other fibres as well as the means of evaluation and control. 

How to prepare

Candidates can prepare by self-study, but are recommended to follow appropriate in-company training, University course or other course provided by a reputable training provider.

Learning objectives 

On successful completion of this examination, you should be able to: 

  • describe the composition, nature and properties of asbestos, and machine made mineral and other fibres and their historical uses;
  • describe the health effects of asbestos and other fibrous materials and apply appropriate exposure limits;
  • describe the uses of asbestos in buildings and the public health risk that these may pose; 
  • understand the principles of and requirements for asbestos surveys including taking samples and identifying bulk asbestos types by microscopic techniques including relevant safety requirements; 
  • be thoroughly familiar with current good practice in the construction and use of enclosures for asbestos remediation and the use of decontamination units; 
  • understand all the principles of clearance testing, the requirements for measurement and appropriate techniques for post-remediation evaluation;
  • conduct air sampling to determine airborne concentrations of asbestos or other fibres in accordance with defined procedures including microscopic counting techniques; 
  • have the ability to advise on all the various techniques for the management of asbestos in buildings in accordance with good practice. 


There will be a 40 short answer question “open book” examination with an allowed time of 120 minutes. 

M504 is recognised for the purpose of professional training and education by the Faculty of Occupational Hygiene, the Professional Standards Body for UK Occupational Hygiene, Chartered Professional Body and statutory body for the recognition in the UK of overseas professional qualifications in Industrial/Occupational Hygiene.

BOHS is no longer an authorised examining body for the OHTA W504 module or part of the OHTA international training scheme and qualifications framework.

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