COSHH: The Complete Guide to Chemical Safety in the Workplace.

When you hear the word chemicals, you might picture bubbling test tubes in a lab, and maybe a mad scientist mixing green liquids with purple liquids to create a new lethal substance that they can use to take over the world. (Just me?)

In reality though, hazardous substances are part of almost every workplace. Dust, fumes, vapours, paints, adhesives, cleaning products, even printer ink – these all fall under COSHH.

But what exactly is COSHH, why does it matter, and how can both employers and employees play their part in keeping people safe? Let’s go full mad scientist and find out. 

What is COSHH?

COSHH regulations UK (Control of Substances Hazardous to Health) are a legal framework designed to protect employees from the risks of hazardous substances at work.

The scope is far wider than just liquid chemicals in bottles; COSHH covers dusts, vapours, gases, biological agents, and even harmful by-products created during work, such as welding fumes or silica dust from cutting concrete.

If a substance can damage health, a COSHH assessment is required.

Why COSHH Matters

Hazardous substances can cause anything from mild eye or skin irritation to long-term respiratory conditions, cancers, or other life-altering health issues. COSHH exists to prevent these outcomes by ensuring risks are identified, understood, and controlled.

For employers, COSHH compliance is central to creating a safer workplace, reducing sickness absence, boosting productivity, and protecting your reputation. On the other hand, failure to comply with COSHH regulations can result in heavy fines, legal action, and long-term reputational damage. 

So while COSHH can feel like a box-ticking at times, it’s not something you want to brush to the side. It will spare you a lot of grief in the long run and, in some environments, could save lives. 

COSHH Assessments: The Starting Point

The foundation of compliance is the COSHH risk assessment. This works like a general risk assessment but focuses specifically on hazardous substances.

Employers must identify every hazardous substance used or produced in the workplace, then review the Safety Data Sheet (SDS) provided by suppliers. SDS documents outline hazards, workplace exposure limits, and safe handling requirements – but an effective COSHH assessment also considers how substances are actually used in practice.

For example, paint that is brushed onto a surface carries different risks compared to paint that is sprayed, because spraying produces airborne particles. These details directly influence which COSHH control measures are needed, such as local exhaust ventilation, restricted work areas, or PPE under COSHH.

Assessments must always be documented, shared with staff, and reviewed regularly.

Storage, Handling, and Disposal

As well outlining how to use chemicals safely, COSHH also governs how they are stored and disposed of.

Hazardous substances must be kept in secure, clearly labelled containers that prevent leaks or spills. COSHH storage cabinets are widely used as they are lockable, fire-resistant, and bunded (able to catch any leakage). Employers must also ensure incompatible substances are not stored together – for instance, oxidisers and flammables should always be separated.

When it comes to handling, only trained employees should manage hazardous substances, using the correct protective equipment for each task. Cutting corners – such as decanting chemicals into unlabelled bottles – is a dangerous practice that has led to serious workplace accidents.

Finally, disposal must be handled responsibly. Hazardous waste cannot go down the drain or into general waste. Instead, businesses should work with licensed waste carriers to ensure safe and legal disposal.

Training, Labels, and PPE

COSHH training is essential for compliance. Employees need to understand the hazardous substances they work with, how to use control measures effectively, and what to do in an emergency. Refresher sessions, toolbox talks, and scenario-based training help reinforce this knowledge and keep awareness high.

Clear labelling is another cornerstone of COSHH. The system of globally recognised hazard pictograms allows workers to instantly recognise whether a substance is corrosive, toxic, flammable, or an environmental hazard. Employers must ensure staff can read and understand these labels correctly.

In some cases, Personal Protective Equipment (PPE) will be required. PPE might include gloves, goggles, face shields, or respirators, depending on the risks. Under COSHH, PPE is always considered the last line of defence – employers should first aim to eliminate or substitute the hazard, or control exposure through engineering and organisational measures.

Employee Responsibilities Under COSHH

Employers carry the legal duty under COSHH, but employees also have responsibilities. They must use controls correctly, wear any PPE provided, and follow safe handling procedures. They also need to maintain good hygiene, such as washing hands before eating or drinking and avoiding contaminated areas.

Another key responsibility is reporting COSHH concerns. If PPE is damaged, if labels are missing, or if a spill occurs, employees must alert supervisors immediately. Active participation by employees ensures COSHH compliance becomes part of day-to-day culture, rather than a paper exercise.

Emergency Preparedness

No matter how carefully substances are controlled, accidents can still happen. COSHH requires employers to have an emergency plan in place for spills, leaks, or exposures. This means having the right equipment on site (spill kits, eyewash stations, first aid supplies) and ensuring staff know exactly what to do.

Training should also extend to first aiders, who need to be prepared for chemical-related incidents with the correct knowledge and equipment.

iSAFE: Your Partner in COSHH Compliance

Managing hazardous substances is not optional. COSHH regulations UK are a legal requirement, but more than that, they are a way to protect your people and your business. Done well, COSHH compliance reduces risk, improves productivity, and ensures your workplace runs safely and smoothly.

At iSAFE, we provide expert support in every aspect of COSHH compliance – from carrying out detailed assessments and delivering practical COSHH training, to developing emergency procedures tailored to your workplace.

If you want peace of mind that your business is COSHH-compliant, contact iSAFE today.