The essentials: dealing with hazardous substances

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Chemical substances are used in a wide and diverse number of industries. But COSHH data sheets are often confused with a COSHH assessment. Whereas lots of technical information may be available, it is essential that particular uses are considered and protective measures communicated to users in a manner they can easily understand.

A large number of companies use chemical substances in manufacturing products, others in equipment servicing and maintenance, agriculture, transport and building construction, to name but a few. Product-related hazards and their potential effects on users, the quantities involved, the recurrence of exposures and the nature of the hazard severities all need to be considered.

Understanding the technical information is very important, as many businesses in the UK employ workers whose first language is not English. There is also the case of those in supervisory positions who may receive chemical safety information written in technical terms and do not know how to best make effective use of it.

The term ‘Control of Substances Hazardous to Health (COSHH) data sheet’ is often heard in the workplace and most of the time confused with a COSHH assessment. Considering the difference between hazard and risk can make it easier to identify the distinction between a safety data sheet and a COSHH record.

The safety data sheet describes the hazards of the material and also provides information and guidance for users. Hazards are an intrinsic property of a material. For example, concentrated sulphuric acid is always corrosive – that is its hazard – and while it remains undisturbed in its container, nobody is likely to be harmed by it. However, as soon as it is being used, there is a real likelihood of harm being caused. This is the risk.

COSHH risk assessment, such as the COSHH Essentials published by HSE, on the other side, is concerned with determining the type and extent of harm that may be caused, who may be affected and how the risk of harm can be eliminated or controlled for the material being used, in the quantities being used, for activities specific to each process within each workplace. There can be no such thing as a generic COSHH assessment – which is why a safety data sheet can never be a ‘COSHH data sheet’.

COSHH risk assessment is also required for hazardous products or by-products generated during work activities, such as dusts, fumes, waste streams. Safety data sheets do not exist for these. Operatives and users of chemicals are not normally concerned with the detail of a COSHH risk assessment and they certainly do not want to read safety data sheets. Instead they usually just want to know how a hazardous material may affect them. It is up to managers to communicate this information to them as well as setting up a safe system of work.

If the safe system of work involves the use of hazard control measures such as ventilation/extraction equipment or personal protective clothing, managers must ensure that users of the hazardous material are aware of these controls and use them correctly.

Not only do users have the right to know about the hazards and risks they may be facing, they also need to know about emergency actions to take if they are accidentally exposed to a chemical. This information should be readily available because any delay in treating a casualty, for example having to find the safety data sheet for details of first aid treatments, may have disastrous consequences.

Dealing with emergencies may also be the subject of a separate COSHH risk assessment, bearing in mind that exposure to hazards could be potentially greater than during normal work processes and may involve working under pressure to deal with the situation as quickly as possible.

Any information that is communicated to the workforce must be straightforward, clear, accurate and relevant. Research has shown that the use of clear and uncluttered charts, posters and signs with minimum of text and emphasis in the pictures or symbols improve the understanding of the risks.

Safety data sheets are not COSHH sheets. Safety data sheets contain technical and chemical-specific information along with guidance for use and emergency measures.

COSHH assessment for a hazardous material is unique to each workplace and often to each activity. The risk depends on what is being used, how much is used, how it is used, who uses it, any contributing factors, e.g. temperature. The assessment includes identification of suitable control measures, which may include engineering controls and personal protective equipment.

Guidance may be obtained from the safety data sheet but the final choice rests with the employer.

Guidance on the REACH chemical registration scheme and safety data sheets can be found here.

COSHH Essentials is available here

Sam Awolesi is senior consultant at Environmental Science Limited.



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