COSHH and safety data sheets: what they mean for laboratory reagents

COSHH stands for the Control of Substances Hazardous to Health Regulations 2002. It is the UK law that requires employers to control exposure to hazardous substances at work, including the chemicals and reagents used in laboratories. A safety data sheet (SDS) is the document a supplier provides with a chemical. It is the main source of information for a COSHH assessment. This guide explains both, and how to read the hazard pictograms on a label.

Terms are defined in the glossary.

What COSHH covers

COSHH applies to substances that can harm health when people are exposed to them at work. That includes:

• chemicals and products that contain chemicals,
• dusts, fumes, vapours, mists and gases,
• substances produced by a process, such as dust from cutting or fumes from welding, and
• biological agents, such as bacteria and other micro-organisms.

It doesn't cover:

• lead and asbestos, which have their own regulations: the Control of Lead at Work Regulations 2002 and the Control of Asbestos Regulations 2012,
• hazards that come only from physical properties, such as being radioactive, explosive, flammable, very hot, very cold or under high pressure. Flammable and explosive substances are covered by other regulations (DSEAR) (COSHH regulation 5).

A substance doesn't need a hazard label to come under COSHH. The HSE points out that harmful substances can also be produced during a process, and that any substance with a workplace exposure limit counts as hazardous to health (HSE).

Who is responsible

COSHH duties fall on employers. In a laboratory that means the university, company or institute running it. Employers must assess the risks, put controls in place, and make sure staff are trained and supervised. Employees have a duty to follow the controls and use the equipment provided.

In practice, labs usually have a named safety lead and a set of COSHH assessments for the substances and procedures they use. A new reagent normally needs checking against that before first use.

How a COSHH assessment works

The HSE sets out the process in five broad steps (HSE):

1. Identify the hazards. Read the label and safety data sheet for each substance. Think about substances your process creates, such as dust when weighing powders.
2. Assess the risks. Who could be exposed, how (breathing it in, skin contact, swallowing) and how much.
3. Control the risks. Work through the options in order of effectiveness, listed below.
4. Record your findings. Employers with five or more employees must write the assessment down.
5. Review your controls. Check they work, and update the assessment when something changes.

Controls, from most to least effective

• Elimination or substitution. Don't use the substance, or use a less hazardous one.
• Changing the process. For example, buy a solution instead of weighing out a dusty powder.
• Containment. A fume cupboard, enclosed balance or glove box keeps the substance away from the person.
• Systems of work. Limit who handles it, for how long and where.
• Cleaning. Clean up spills and dust promptly and safely.
• Personal protective equipment (PPE). Gloves, lab coat and eye protection, chosen to suit the substance. PPE is the last line of defence, not the first.
• Information and training. Everyone who handles the substance should know its hazards and the controls.

The HSE's principles of good control practice set out the same thinking in more detail.

What a safety data sheet contains

A safety data sheet has 16 sections, always in the same order (UK REACH, Annex II):

For a COSHH assessment, sections 2, 7, 8 and 13 do most of the work. Always check the revision date in section 16, and use the latest version.

When a supplier must provide one

A supplier must provide a safety data sheet when a substance or mixture is classified as hazardous, or meets certain other criteria for persistent or very harmful substances (UK REACH, Article 31). Many suppliers provide one for unclassified products too, so that buyers have the information in a standard format.

"Not fully tested"

Many research chemicals, including most research peptides, have not been fully tested for health effects. Their safety data sheets often say so in section 11. That is not the same as being safe. The usual approach is to treat a substance with unknown effects with care: avoid making dust, avoid skin contact, and work in a way that limits exposure.

Hazard pictograms

In Great Britain, chemical labels and safety data sheets use the hazard pictograms set out under GB CLP, based on the UN's Globally Harmonised System (GHS). Each is a black symbol in a red-bordered diamond (HSE):

Labels also carry a signal word, either "Danger" for more severe hazards or "Warning" for less severe ones. Hazard statements (H-codes, such as H315 "Causes skin irritation") describe the hazard. Precautionary statements (P-codes, such as P280 "Wear protective gloves") describe what to do.

Laboratory reagents in practice

• Weighing powders is often the step with the most exposure, because fine powders can become airborne. An enclosed balance or a fume cupboard helps. For handling freeze-dried peptides, see hygroscopic powders.
• Solvents such as acetic acid carry their own hazards. The acetic acid guide covers it as a solvent, and its supplier's safety data sheet covers its hazards.
• Storage should follow section 7 of the safety data sheet and the product page. See how to store lyophilised peptides.
• Disposal should follow section 13 and your organisation's waste procedures. Don't pour chemicals down the sink unless the safety data sheet and local rules allow it.
• Records. Keep the lot number with each COSHH record and experiment. See lot numbers and batch numbers.

Our safety data sheets

Each product page has a "Safety data sheet" link in its resources. Where a sheet isn't yet published, the page says it is available on request and links to our contact page. A safety data sheet is separate from a certificate of analysis (COA): the SDS covers hazards and safe handling, and the COA covers the tested quality of one lot. See what a certificate of analysis tells you.

This guide gives general information about the law. It isn't legal advice, and it doesn't replace your organisation's own COSHH assessments. For the full requirements, see the HSE's COSHH guidance.

Related guides

For what "research use only" means, see are peptides legal in the UK. Every lot has its own COA, published on the product page and on that lot's own page. See Quality.