When Is A COSHH Assessment Required?

When is a COSHH assessment required? Is it when you purchase a hazardous substance? Or when you do an activity involving it?

You need a COSHH assessment whenever you are using, creating or producing a substance within your workplace that is hazardous to health.

What is the law for COSHH assessments?

COSHH assessments are more than just good health and safety - they are a legal requirement.

Required by the Control of Substances Hazardous to Health Regulations, COSHH assessments have their own section. Section 6. With the catchy title "Assessment of the risk to health created by work involving substances hazardous to health".

The law says that you shouldn't start any work that exposes employees to substances hazardous to health unless you have:

• Assessed the risk
• Assessed the steps (controls) needed to make it safe
• Put those steps in place

6.—(1) An employer shall not carry out work which is liable to expose any employees to any substance hazardous to health unless he has—

1. made a suitable and sufficient assessment of the risk created by that work to the health of those employees and of the steps that need to be taken to meet the requirements of these Regulations; and
2. implemented the steps referred to in sub-paragraph (a).

When should you do your COSHH assessment?

So COSHH assessments are required by law, but when should you assess a substance?

• When you're using it?
• When you're ordering it?
• When it has been used?

The answer can be found within the regulations themselves:

6.—(1) An employer shall not carry out work which is liable to expose any employees to any substance hazardous to health unless he has—

1. made a suitable and sufficient assessment of the risk created by that work to the health of those employees and of the steps that need to be taken to meet the requirements of these Regulations; and
2. implemented the steps referred to in sub-paragraph (a).

The regulations say you will not carry out work that could expose employees to a hazardous substance unless you have carried out your assessment, and put in place any steps needed to control the risks.

Your COSHH assessment should, therefore, get carried out before any activity takes place that uses, involves or exposes employees to substances that are hazardous to health.

That means you can't complete work that involves the use or production of a hazardous substance until you have carried out your COSHH assessment.

So complete your COSHH assessment before you are exposed.

Well, that makes sense, if it's hazardous, it's no good assessing it when you have already come into contact with it! You may have already been harmed.

How do you know when you expose employees to hazardous substances?

Now you know that you need to carry out a COSHH assessment before exposing employees to substances hazardous to health. But sometimes, that's easier said than done.

Substances that are hazardous to health include any substance or preparation (mixture) with the potential to cause harm if they are inhaled, ingested, come into contact with, or are absorbed through the skin.

Often, it will be obvious when work involves a hazardous substance.

The easiest hazardous substances to spot are the ones that tell you they are hazardous. They give you this information when you purchase them.

Hazardous substances will have information on packaging and manufacturer's details for the hazards they present. An eye-catching red hazard symbol might tell you it is toxic or flammable.

But there could be other hazardous substances in your workplace. Ones you don't purchase.

What about the substances you create during your work? For example, if you drill concrete or sand wood, the dust you make should be assessed under COSHH.

Concete creates harmful silica dust, and some wood dust can cause cancer.

Unfortunately, these substances don't tell you about their hazards when you don't buy them in helpful packaging. You might need to take samples or find out about the material for yourself.

To help identify the substances you need to assess, keep an inventory of hazardous substances using the free COSHH register.

What information does a COSHH assessment require?

Once you have identified a hazardous substance, and know you need a COSHH assessment, you have to create one!

But don't worry, a COSHH assessment is just a risk assessment for a hazardous substance. If you know how to write a risk assessment, a COSHH assessment is very similar.

But you will need to include some extra information, like:

• The hazardous properties of the substance
• The potential health effects
• The level, type and duration of exposure
• Details of the work and amount of substances involved
• Exposure limits WELs
• How you will prevent and control exposure
• Results of monitoring
• Results of health surveillance

Find out more about what to include in what is a COSHH assessment.

By completing a COSHH risk assessment, you will be able to decide which control measures are needed to prevent or control the exposure of employees to substances hazardous to health.

Here are 7 types of COSHH control measures and how they reduce risks.

You may need to refer to the supplier's safety data sheets to help you complete your COSHH assessment. This information will give you details of the specific risks associated with the substance, and help you to assess if your existing practices are sufficient to ensure adequate control of exposure.

However, it is important to remember that simply collecting supplier data sheets will not meet the requirements of COSHH, and you must complete a COSHH risk assessment specific to the task you do.

Your assessment may be initial or conditional, if this is the first time you have introduced a new substance, for example, you may need to test control measures to confirm effectiveness.

For example, you might provide specific PPE as a result of your COSHH assessment, but on evaluating the process you may determine that this PPE is not necessary. In this case, you can then update your COSHH assessment to reflect these findings.

You can use the free blank COSHH assessment template to get an idea of the layout and format you will need.

When should you review your COSHH assessment?

Now you know when you need to complete a COSHH assessment, but that's not the end of the matter. Just because you have a COSHH assessment in place, doesn't mean you can forget about it!

You will need to review your COSHH assessment regularly, and immediately if:

• If it is no longer valid
• If there is a change to the work
• Monitoring results show it's necessary to review

You should review your COSHH assessment even if no known changes occur. The reason for regular reviews is that over time gradual changes can occur that may go unnoticed. But these changes could make the original assessment insufficient or unsuitable.

In addition to regular reviews, you should review your assessment immediately if your existing assessment becomes invalid.

An assessment could be invalid because of significant changes in the work process or circumstances, reports from supervisors about defects in control systems, or the results of testing control measures.

How often you periodically review your COSHH assessment will depend on the level of risk, and the task being carried out. It's good practice to review COSHH assessments at least annually, and more often for higher risk substances and procedures.

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If you need help producing COSHH assessments for your business, check out our COSHH assessment templates, or get started with the free blank COSHH assessment template.