Decoding EH40 Workplace Exposure Limits: Safeguarding Workers’ Health

Understanding EH40 workplace exposure limits is an important factor to consider for compliance, health and safety. That’s because, ultimately, workplaces are responsible for upholding mandatory compliance measures in line with occupational health and hygiene. Today, we’re going to explore what EH40 is, what it entails and how you can carry out a COSHH assessment to ensure your workplace is compliant.

What does EH40 mean?

EH40 Workplace Exposure Limits is a publication by the Health and Safety Executive (HSE) in the UK. The specific document is titled “EH40/2005 Workplace Exposure Limits”, though is more commonly referred to as EH40 in the workplace. 

The EH40 regulations document is designed to provide guidance on exposure to hazardous substances that could be detrimental to employees if they aren’t handled correctly. These limits are updated regularly with the advancement of new technologies, research and changes in legislation. In fact, the latest update to the EH40/2005 Workplace Exposure Limits publication was made back in January 2020. It goes without saying that all employers must comply with EH40 to ensure employees work in a safe environment.

What do workplace exposure limits mean?

As we touched upon briefly, workplace exposure limits (WELs) are a set of guidelines used to protect employees from harmful substances. These guidelines detail occupational exposure limits which are approved (and regularly reviewed) by the HSE. The types of substances detailed in the EH40/2005 Workplace Exposure Limits include:

• Dust (including combustible dust, silica dust, wood dust and more)
• Harsh chemicals
• Vapours
• Mists
• Nanotechnology
• Biological agents
• Germs and microbes
• Fumes

These form part of a wider COSHH workplace regulation system. However, the three main exceptions to standard WELs are:

• Lead
• Asbestos
• Radioactivity

Updates to EH40/2005 workplace exposure limits

As of the 17th January 2020, 13 new substances were added to the document by the Carcinogens and Mutagens Directive (EU) 2017/2398 amending Directive (2004/37/EC) and guides those responsible for controlling exposure to hazardous substances at work. It’s also worth noting that the 2020 EH40 edition replaces the previous version (published in 2018) and accounts for the new and amended occupational exposure limits. New substances include:

• Hardwood dust (including mixed dust)
• Chromium (VI) compounds
• Refractory ceramic fibres
• Respirable crystalline silica
• Vinyl chloride monomer
• Ethylene oxide
• 1,2-Epoxypropane
• Acrylamide
• 2-Nitropropane
• O-Toluidine
• 1,3-Butadiene
• Hydrazine
• Bromoethylene

Why are workplace exposure limits important?

EH40 workplace exposure limits are important for safeguarding employees from hazardous substances damaging their health. This is why ventilation is important in the workplace, among other systems which we’ll dive into shortly. Though WELs are approved measures by the HSE, they are regularly reviewed to ensure the concentration of these substances in the workplace (over a set period of time) is under control.

The way in which these substances can harm workers include:

• Breathing in spaces where dust, fumes, gases or mist are present
• Direct skin contact 
• Injecting into the skin
• Swallowing

How do workplace exposure limits affect the workplace?

If the place of work handles hazardous substances, they’re going to affect workers’ health if they aren’t managed correctly. By having the right measures in place, you can ensure:

• A safer place for people to work
• Happier and healthier staff
• Reduced sickness rates
• Avoid the fee of intervetion (FFI) – which is currently set at an hourly rate of £166 since April 2023

That last point is particularly important. An FFI must be paid if HSE inspectors find a breach when they suspect non-compliance. The fee is designed to cover the costs in identifying the problems and the steps to rectify any issues. You won’t be charged if nothing is found during their inspection.

How EH40 workplace exposure limits work

As we’ve already established – EH40 WELs are designed to protect workers from hazardous substances in the workplace. But how are these limits set and how do they work?

EH40 is set out into two separate measurements: short-term exposure limits (STELs) and long-term exposure limits (LTELs). Essentially, LTELs are set by analysing the concentrations of hazardous substances over an eight-hour working day and are then set as a time-weighted average (TWA). The same can be said for STELs (and ceiling limits), but the TWA is measured over a 15-minute period. 

Ceiling limits are the maximum concentration of a hazardous substance to which a person can be exposed. There is no set exposure time limit when it comes to ceiling limits because it’s designed to represent a concentration that is immediately hazardous and should be avoided altogether.

How are workplace exposures measured?

Every substance listed in the HSE has its own levels and limits set by the HSE. These are noted in parts per million (ppm) and milligrams per cubic metre (mg/m3). You can find the full list of exposure limits in the EH40 Workplace Exposure Limits document.

For a place of work to comply with EH40 – the employer needs to identify what the hazardous substances are, and where they could occur within the workplace. They then must measure the concentration of these substances in the air. If the exposure limits exceed the WELs for a particular substance, steps must be taken to reduce the exposure. 

How to reduce EH40 exposure limits in the workplace

In order to comply with EH40 regulations, particularly when exposure limits have been exceeded, workplaces will need to implement particular measures, provide personal protective equipment (PPE) and the like. Here are some examples of ways you can reduce exposure limits:

Conduct a COSHH assessment

What is COSHH? The Control of Substances Hazardous to Health is a legal assessment employers must carry out. They not only identify the areas where hazardous substances are present, but they also ensure the safety of yourself and your employees. Ultimately, high exposure limits are harmful to health, and without assessing and regulating the atmosphere in which employees work in, it can land you in some serious legal trouble.

The COSHH assessment of your work will involve analysing every area of business operations, to identify where hazardous substances listed in EH40 might be present. Once the assessment has been carried out, you can determine which substances can (or are) affecting workers’ health and how. The final part of the assessment will look at preventative measures to ensure the health of employees – whether that be reducing the risks or eliminating them altogether.

Consider ventilation solutions

Industrial ventilation solutions and other types of control equipment will need to be considered to reduce and/or prevent hazardous substances in the air. Some of the more common units considered include dust extraction or bespoke ductwork systems. You’ll then need guidance on how to maintain extraction and ventilation systems in order to remain compliant with EH40 regulations. This could involve regular testing, maintenance and emergency procedures in the case of contamination, spills, combustion and the like.

Conduct regular training

Whilst implementing control measures to reduce EH40 workplace exposure limits helps with compliance, keeping staff trained on maintenance and emergency procedures is important too. Try to determine if extra training is required – whether this is in the form of regular workshops, qualifications and/or training certificates. The competencies in maintaining EH40 compliance can also help set a chain of command and allocate dedicated staff to go to in regard to workplace exposure limits.

Follow the hierarchy of control

Generally, PPE should only be utilised as a last resort to protect against exceeded EH40 workplace exposure limits, accidents, non-compliance and any other faults that put workers at risk. The recommended hierarchy of controls against high exposure limits include:

• Elimination: This involves physically removing the hazard
• Substitution: replacing it with a safer alternative to the source of the hazard
• Engineering controls: isolating people away from the hazard
• Administrative controls – change the way people work in the form of new training or job rotations
• PPE: to protect the worker with specialist equipment

It goes without saying, that all staff must be trained on the above to ensure everyones’ safety, as well as know the procedures to report breaches, faults and failures.

Want to reduce WELs and effectively comply with EH40 workplace exposure limits? Airmatic provides a host of solutions for a variety of sectors. Plus, if you need any maintenance, our team of highly trained extraction specialists are always ready to help. Contact Airmatic for air and dust extraction solutions today.