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COSHH Essentials: General Guidance G409 ‘Exposure Measurement: Air Sampling’

21 February 2022

Bethan Stones headshot

Bethan Stones

Group Marketing Manager

In January 2022, the Health and Safety Executive issued an updated guidance document which provides practical advice on when you must measure exposure to airborne substances, how to measure exposure, the substances, demonstrating control, and what should be included in the content of a consultants’ report. 

Key Changes

The key changes to the guidance relate to: –  

  • Number of samples be taken to show compliance against Workplace Exposure Limits 
  • What demonstrates control of exposure to hazardous substances 
  • What is considered fact and what is opinion in consultants’ reports 

Following the guidance will normally be sufficient to be in compliance with the law. 

Need Support?

Envirocare has an experienced team of dedicated occupational hygienists who can competently prepare a sampling strategy as described in the guidance, and are recommended by the BOHS in their ‘Good Practice Guide for Consultants’   

We adopt the relevant HSE Methods for Determining Hazardous Substances (MDHS) and other recognised standards for air monitoring specific substances. These include, but are not limited to: 

  • MDHS 14/4  Respirable, thoracic and inhalable aerosols 
  • MDHS 25/4  Isocyanates    
  • MDHS 47/3  Rubber process dust and rubber fume  
  • MDHS 52/4  Hexavalent chromium  
  • MDHS 83/3  Resin acids in rosin (colophony) solder flux fume 
  • MDHS 84/2  Oil mist from mineral oil-based metalworking fluids 
  • MDHS 95/3  Water-mix metalworking fluid 
  • MDHS 101/2  Respirable crystalline silica   
  • MDHS 102 Aldehydes 
  • MDHS 104 Volatile Organic Compounds 
  • ISO 10882  Welding fume

Our interpretive reports compare the monitoring results with workplace exposure limits (WEL) and provide practical cost effective control measures. WELs are published in HSE publication EH40 ‘Workplace Exposure Limits’ Workplace Exposure Limits: COSHH Regulations Explained