7 Types Of COSHH Control Measures And How They Reduce Risk

If you work with hazardous substances (and most businesses do), you need to control the risks. It's one of the legal requirements of the COSHH regulations.

Because hazardous substances are called hazardous for a reason - they can harm people's health. In some cases, these substances can cause severe and permanent damage.

If people get exposed to a toxic substance, for example, it could kill them. But it doesn't even have to be toxic to cause serious harm. Materials like concrete or wood can release dust that can cause cancer or respiratory problems that, over time, are fatal.

Considering how serious the consequences are, it's no surprise that there are laws in place to protect people.

The law (COSHH) puts duties on employers to reduce the risk of exposure to hazardous substances.

(3) Where it is not reasonably practicable to prevent exposure to a substance hazardous to health, the employer shall comply with his duty of control under paragraph (1) by applying protection measures appropriate to the activity and consistent with the risk assessment, including, in order of priority—

1. the design and use of appropriate work processes, systems and engineering controls and the provision and use of suitable work equipment and materials;
2. the control of exposure at source, including adequate ventilation systems and appropriate organisational measures; and
3. where adequate control of exposure cannot be achieved by other means, the provision of suitable personal protective equipment in addition to the measures required by sub-paragraphs (a) and (b).

Specifically, COSHH says that if you cannot prevent exposure, you must control it. And in the same way that carrying out a COSHH assessment is a legal requirement, so is the need to control the hazards and risks you identify.

And the regulations even give you a clue as to the type of controls you should consider.

If you have read our post on the principles of prevention, you will know that not all control measures are equal, and that's why the COSHH regulations tell you to prioritise the control of systems over PPE.

Some controls are more effective than others.

So what protection measures are best for COSHH, and in what order of priority?

Here are 7 types of COSHH control measures, in order of priority, with details on how they reduce the risk from hazardous substances.

1. Elimination

The COSHH regulations first require exposure to be prevented. You can prevent exposure by eliminating your use of hazardous substances and getting rid of the risk in the first place.

• Remove the hazardous substance

Elimination might involve changing a process to avoid the use (or creation) of the substance. And while it sounds like a lot of work, if you can do this, the bonus is that COSHH will no longer apply - there is no hazardous substance!

(1) Every employer shall ensure that the exposure of his employees to substances hazardous to health is either prevented or, where this is not reasonably practicable, adequately controlled.

Of course, it's not always possible to eliminate a substance. Sometimes, hazardous substances need to be used, so you can't entirely prevent the risk of exposure. If you can't eliminate it, you need to start thinking about how the risk can be controlled.

2. Substitution

Another way to prevent exposure to a hazardous substance is to substitute it for a less hazardous alternative.

Instead of eliminating the risk, you are reducing it.

• Swap for lower hazard alternative
• Change the substance to a safer form

An example of this could be changing from oil-based to water-based paints. Or moving from a chemical-based cleaning product to a more natural alternative.

You might also substitute or even change a product to a safer form. For example, you could use a paste rather than a spray.

Another example would be to dampen down dust during drilling so that it doesn't become airborne. The substance is still there, but it's less hazardous now because it can't be breathed in by workers.

With thousands of products available, a review of various suppliers can often result in finding lower hazard alternatives.

3. Change Processes

Can the process be changed to reduce exposure to hazardous substances?

If you review the way you work, it might highlight COSHH problems. For example, it might be standard practice for operatives to sweep up after finishing work, causing settled dust to become airborne again.

Changing the process to damp down before sweeping or cleaning up, or using damp rags to clean up, will help prevent dust clouds and make the workplace safer (and healthier) for everyone.

4. Engineering Controls

Engineering controls are the next option on our list. This involves the design of systems and work equipment to control exposure, ideally at the source to prevent (or greatly reduce) exposure to a safe level.

You can use engineering controls to enclose the process and prevent the hazardous substance from escaping outside the enclosure. You can also use engineering controls to extract emissions at or near the source.

These controls might include:

• Segregation of people
• Local exhaust ventilation
• Dilution
• General ventilation

5. Supervisory Controls

As an employer, you must make sure that the COSHH control measures work properly through regular monitoring, checks and supervision.

You might also have rules to keep exposure minimised to a safe level.

These supervisory controls could include:

• Reduced time exposure
• Reduce the number of people exposed
• Prohibitions and rules

For example, you might say that only particular people are allowed within a COSHH enclosure, and they must have certain training and be wearing and using specific equipment.

Supervisory controls usually have to be enforced, because, unlike engineering controls, they rely on being followed and obeyed.

6. PPE

When you think about control measures, personal protective equipment (PPE) is often one of the first things that might come to mind, so why is it one of the last items on our list?

PPE is near the bottom because, while it's an important control, PPE is a last resort control measure.

• It only controls the risk to one person at a time
• Doesn't reduce the hazard
• Relies on being fitted and worn correctly

Because it doesn't reduce the hazard - if PPE fails, it exposes the wearer to the maximum health risk. So you should never rely on PPE alone. It's always best to combat the hazard at the source first to reduce the risk.

Nonetheless, PPE is still an important control measure. To be effective it should fit the user, and be comfortable and suitable for the risks they are likely to be exposed to.

7. Combined Controls

Often the best way to implement COSHH control and get the risk adequately controlled is by combining control measures.

You might use control equipment in addition to PPE.

You might substitute a hazardous substance for a lower-risk substance but still needs to have other controls in place, like dust suppression, enclosures and PPE.

For maximum risk reduction, use a combination of control measures. Each measure reduces exposure a little bit more until you are at a safe level. And if one control fails, at least you have others to fall back on.

When you are using a mixture of control measures, they all must work together. Remember to look at the process as a whole, and consider how each control impacts another.

For example, if you substitute a powder for a paste to lower the risk of inhalation, you may also need to change the user's PPE and give more protection for skin contact, rather than respiratory protection.

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Need help preparing your COSHH assessment? Use our free blank COSHH assessment template, or browse through our ready-to-use COSHH templates.