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  • Writer's pictureDale Allen

Top 5 COSHH Assessment Mistakes You May Be Making

Updated: Sep 21, 2022

Unfortunately, even today, there are a lot of employers who still don't understand the COSHH regulations and what is required of them.

Employers whose company uses dangerous chemicals, or produces hazardous substances through a work process, are required to perform COSHH assessments on every one of those work activities.

However, they get confused by the assessment process and often use inadequate assessment techniques. This usually means that the control measures they decide on during the assessment process aren't sufficient to control the risk presented by the hazard.

Here are the top 5 COSHH assessment mistakes you may be making:

Allowing untrained, incompetent staff to conduct your COSHH assessment

This is an important question to ask yourself, whether you're working with a high or low-risk situation. It doesn't matter how much of an enthusiast you are, if you don't have the right training and experience with specific processes, your assessments are going to be incomplete.

It's very easy for inexperienced assessors to miss critical points, endangering your workplace and the rest of your employees due to uncontrolled risks.

The most common mistake inexperienced COSHH assessors make is concentrating on the completely wrong thing, usually because they're confused about the difference between a risk and a hazard.

This generally means the assessor concentrates on the substances instead of properly assessing the work process. An assessment should cover the task as a whole, what is used during it, how long for, and what may be created by the process.

For example:

You've just installed a new workstation for dressing aluminium castings.

You need several tools to do your task, all of them requiring an oil to ensure the blades operate as intended when dressing the surface of the casting.

The work process itself also creates hazardous substances as it is being carried out. In the form of fumes, vapours, dust, and fine-particulates made up of the oil and tiny pieces of the blades and aluminium.

Before your work can begin you need to perform a chemical risk assessment.

You choose to do a substance assessment of the oil and the hazards it presents because it's the only substance you currently know of being used for your task.

Because you lack training in a proper COSHH assessment methodology you neglect to assess the task itself, including how the oil will react as you proceed.

You also don't take into account the hazardous substances that are likely to be produced as you do your work, where they will go and how they can affect the entire workstation.

Using Safety Data Sheets as COSHH Assessments

I was looking through the results of my surveys I conducted several months back.

One of them was called 'Is your business compliant with chemical safety law? (COSHH).

Why did I do it?

Well, that's easy to answer. I did it because, at the time, I needed to know which areas of chemical safety people are struggling with.

I let the survey run over the course of a week. It contained 14 multiple-choice, COSHH related questions.

When I closed down the survey and looked through the results, I was completely shocked by what I was reading!

230 people started that survey.

Alarmingly, though, 414 started it!

The questions - as you might expect with them being COSHH related - were meant to assess the compliance of the person's business based on the principles of the Health and Safety Executive's COSHH Regulations.

Honestly, though, I messed up. The survey was completely flawed (more on this later.)

It became evident from the results that one simple misunderstanding on their part could lead to huge breaches of safety.

And worse still, at the time I believed they were doing the right thing!

So, this is where we get back to my flawed survey and the reason I believed they were right at the time.

I decided to check through the people who had scored a compliance pass.

Everything was looking great, and because I work backwards (as in ending to the beginning) it wasn't until I got all the way to question 4 that I realised my mistake.

The question was: 'How do you create your COSHH assessments?'

I noticed that a lot of people had chosen the answer, 'We use Safety Data Sheets as our COSHH assessments!'

Oh no! Really?!

And this is the worst part, the mistake I made. My survey told the people who gave this answer, 'Congratulations, you are compliant!'

Uh oh! How on Earth?!

I obviously know that safety data sheets can't simply be used as a chemical risk assessment, but I had weighted my survey to give them a pass if they correctly answered a certain amount of questions.

It didn't matter which questions they got right or wrong, once they hit that magic number of correct answers, they got a message saying they had passed.

Even when it's likely their assessments were incomplete.

What I should have done is instantly tell them, 'You are breaking the law!'

Now, are you ready for this?

Alarmingly, of the 230 people who completed that survey, 23.33% of them chose this answer!

You got that right.

That's up to a quarter of businesses in the UK who need to comply with the COSHH regulations may actually be breaching them.

What really needs to be done regarding safety data sheets and COSHH assessments is to take the information from the SDS and use it to conduct a full chemical risk assessment. See the example below:

Neglecting to review your COSHH assessments, especially following workplace changes

This is potentially the most dangerous mistake you can make. Assuming that everything is as safe as it was when you conducted the assessment 18 months ago is asking for trouble.

Nothing ever stays the same.

The work process might be identical but 18 months after you installed them, the control measures may be showing signs of age. Control measures that aren't doing their job are not adequate control measures.

This is obviously a very simple example, but it's important to regularly review your COSHH assessments. And while there is no legal requirement, the HSE (us too) recommend that you review any assessment annually, at the very least.

There are other reasons to take your assessments under review, however.

Ask yourself these questions:

  • Were new hazards introduced?

  • Has there been any change in the level of exposure your employee faces?

  • Have new hazards introduced new risks?

  • How likely is it that the hazard can cause harm, and what would be the severity of that harm?

  • Have any changes been made to the known hazards, and do those changes modify the likelihood, and severity, of a harmful event?

  • Are the existing control measures still adequately controlling the previously known risks?

  • How would you prioritise the new risks?

  • Does that affect your previous priority of the known risks?

  • Can you control the new risks with existing control measures?

  • If no, what control measures can you implement?

Making your COSHH assessments far too complicated

Aren't they supposed to be complicated?

No, they aren't! It's completely unnecessary to over-complicate your chemical risk assessments.

Keep in mind who will be reading it down the line. It needs to be understandable to anyone. Including anyone who might not be very clued up on the COSHH regulations or risk assessments in general.

Anyone not understanding your jargon is going to skim over it and miss the really important information.

When recording your COSHH assessments, you should be clear and concise.

There is nothing worse than seeing a group of ticked check-boxes, but no details on why they were ticked, when they ticked, or even who did the ticking!

Failing to engage your employees in your COSHH assessment and control processes

Your employees are obligated to follow the chemical safety guidelines, just like you. They hold a legal responsibility to use the control measures that you or your managers implement.

While you do, indeed, play the critical role of risk assessor, their jobs are probably more important.

Your employees spend most of their time on the shop floor, with eyes on the hazards that they work around. A very important part of COSHH safety is the reporting of incidents, near-misses or new hazards.

Your employees are the best people to spot those failures or potential new hazards because they're doing the job on a daily basis. Have they take the new COSHH Risk Assessor Certification™.

The New International Chemical Safety Accreditation Course

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Sayem Ahmed kosru
Sayem Ahmed kosru
Aug 31, 2022

As I read through this post on Coshh Stand, It will be amazed at all the fascinating details I'm learning. Each new fact makes me even more excited to learn more about this topic. You've written so well that I feel like I could actually understand Coshh Stand now!

There are other great resources out there for learning reheat prawns, so I'm going to check them out now. But before I go, I just want to say thank you for sharing all of this information with us. It's really helped me understand math in a whole new way.


Apr 13, 2020

Nice Article


Apr 12, 2020

I need to study please can you send me full information COSHH Risk Assessor course.


Apr 12, 2020

I need to study please can you send me full information COSHH Risk Assessor course.

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