In this section, we outline the legal context for and the methods of carrying out inhalation risk assessments.
All workplaces are covered by the Health and Safety at Work etc Act 1974. This sets out the general duties that employers have towards employees and members of the public, and the duties that employees have to themselves and each other. The employer should, so far as is reasonably practicable, protect the health, safety and welfare of employees while at work.
The Management of Health and Safety at Work Regulations 1999 (as amended) gives more detail about the requirements under the Health and Safety at Work Act 1974. These regulations place duties on the employer to assess risks and, where necessary, to take action to safeguard health and safety, including health surveillance if appropriate.
Legal requirements when dealing with dangerous substances are set out in The Control of Substances Hazardous to Health (COSHH) Regulations 2002, as amended 2004. The first requirement is to prevent exposure (both inhalation and skin) to substances hazardous to health. Employers must:
- carry out a risk assessment (regulation 6)
- make sure that exposure to hazardous substances is adequately controlled (regulation 7)
- put in place appropriate control measures which are properly maintained (regulations 8 and 9)
- monitor exposure in the workplace (regulation 10)
- carry out health surveillance (regulation 11)
- provide information, instruction and training to employees exposed to hazardous substances (regulation 12)
Guidance on how these requirements can be achieved is in the accompanying Approved Code of Practice, which is available from the HSE. Appendix 3 of the Code refers specifically to the control of substances that cause occupational asthma. This states that exposure to substances with the potential to cause occupational asthma should be prevented. If this isn’t possible, then exposure should be reduced ‘so far as is reasonably practicable’.
The HSE’s A brief guide to the regulations is a good introduction to COSHH.
Workplace exposure limits (WELs) are set under COSHH to help protect the health of workers. WELs are published by the HSE in Environmental Health Guide 40 (EH40/2005). WELs are set for a hazardous substance by measuring concentrations in the air, averaged over a specific period of time-weighted average or TWA. Two time periods are used: long term (8 hours) and short term (15 minutes). Where the principles of good practice for control are applied, the amount of time a worker should be exposed to a substance will be below the relevant WEL. You can view extracts from the publication, EH40/2005, on the HSE’s Control of Substances Hazardous to Health web page. This includes a list of approved workplace exposure limits and supplementary information.
The control of exposure is only adequate where the WEL is not exceeded and the principles of good practice are applied. These principles are:
- design and operate processes and activities to minimise the emission, release and spread of substances hazardous to health
- take into account all relevant routes of exposure - inhalation, skin absorption and ingestion - when developing control measures
- control exposure by measures that are proportionate to the health risk
- choose the most effective and reliable control options that minimise the escape and spread of hazardous substances
- where adequate control of exposure can’t be achieved through other means, provide, in combination with other control measures, suitable personal protective equipment
- check and review regularly all elements of control measures for their ongoing effectiveness
- inform and train all employees on the hazards and risks from the substances they work with, and tell them about the use of control measures that have been introduced to minimise risk
- make sure that the introduction of control measures doesn’t increase the overall risk to the health and safety of employees and others
Where a substance has been assigned a specific risk phrase, other measures may also be necessary.
Just because a substance isn’t on the list of WELs doesn’t mean that it’s safe. For example, there’s no WEL for animal allergens which can cause occupational asthma. For such substances, exposure should be kept at a level that most of the working population could be exposed to, day after day, without adverse health effects. As part of the COSHH assessment, employers should decide on their own practices, and in-house standards of control. As detailed in the COSHH ACOP (Appendix 3 Control of substances that cause occupational asthma), assessing control measures and good working practices for substances which cause asthma should take account of the seriousness of the health effects which could result from control failures. Advice on appropriate in-house standards of control can be obtained from an occupational physician or occupational hygienist.
There are separate requirements for:
- asbestos, covered in The Control of Asbestos Regulations 2006 and the accompanying Approved Code of Practice (a publication from the HSE)
- lead, covered in The Control of Lead at Work Regulations 2002 - These are the main legal controls that are relevant to inhalation exposure and the prevention of respiratory problems.
The new European Union (EU) chemicals regulation, REACH (Registration, Evaluation, Authorisation and restriction of Chemicals) was brought into force on 1st June 2007 by the European Commission (EC). Under REACH, chemical manufacturers and importers are responsible for the identification and management of the risks associated with their substances. A major element of REACH is the requirement for manufacturers and importers of substances (either on their own, in preparations or articles) in annual volumes of 1 tonne to register them with the European Chemicals Agency (ECHA), with un-registered substances becoming illegal to manufacture, supply and use. Some substances are exempt from these regulations, which mainly include; waste, radioactive materials, substances under customs supervision. non-isolated intermediates, substances being transported and some naturally occurring low-hazard substances. Registration is phased over a number of years based on the manufactured/imported quantities and toxicity of the substances. Further information on complying with REACH is available from the ECHA and HSE websites.
A key aspect of REACH is the requirement for manufacturers and importers of substances to communicate down the supply chain how their substances or preparations can be used safely, through provision of a Safety Data Sheet (SDS). SDS, previously covered under the Chemicals (Hazard Information and Packaging for Supply) Regulations (CHIP), will continue to contain information on the hazards of the substance or preparation and the recommended risk management measures.
More relevant legislation
The Workplace (Health, Safety and Welfare) Regulations 1992
These aim to make sure that employers and others with responsibility meet the minimum standards for the health, safety and welfare of each member of the workforce, and reduce the risks associated with work in or near buildings.
The Personal Protective Equipment at Work Regulations 1992
Personal protective equipment means all equipment (including clothing that protects against bad weather) which is intended to be worn or held by a person at work, and which protects against one or more risks to health or safety, and any addition or accessory designed to meet that objective.
Equality Act 2010
The Act gives rights to people who have or have had a disability which makes it difficult for them to carry out day-to-day activities. The disability could be physical, sensory or mental. It must also be substantial and have a long term effect - it must last or be expected to last for at least 12 months. Severe long-term respiratory diseases may well be covered by the act.
The HSE’s web page on Asthma and other respiratory diseases gives lots of information on occupational respiratory diseases, with links to pages on asthma and chronic obstructive pulmonary disease (COPD).
The HSE also has advice on preventing asthma in high risk jobs. The jobs are:
- vehicle spray painters
- healthcare workers
- laboratory animal workers
- agriculture workers
- engineering workers
The HSE has top tips for a healthy workforce on its COPD web pages. These tips apply not just to preventing COPD but other conditions too.
Identifying the cause of the problem
It’s very important to correctly identify the cause of a respiratory problem and to consider its scale. For example, one case of asthma in a workplace doesn’t necessarily indicate a serious problem. Not all respiratory problems are due to occupational factors, although employers need to consider whether an employees condition could be made worse by work, for example if an employee has pre-existing asthma and their job involves exposure to irritants or dust.
Respiratory protection management programme
To prevent or minimise respiratory problems at work, employers should have a respiratory protection management programme in place. The programme should cover:
- risk assessment
- control measures
- monitoring of exposure
- health surveillance
- and education and training of employees.
The HSE has a questionnaire that employers can use to design a programme for managing metalworking fluids and which may help employers to design a programme for other industries.
Risk assessment tools
Under the COSHH Regulations, when employees work with chemicals, employers must carry out a risk assessment. An HSE leaflet outlines the five steps to risk assessment:
- identify the hazards
- decide who might be harmed and how
- evaluate the risks and decide on precautions
- record your findings and implement them
- review your assessment and update if necessary.
The HSE’s COSHH essentials website, developed to help firms comply with the COSHH Regulations, gives advice on controlling the use of chemicals. The user is asked for information about the process, tasks and use of chemicals before being offered advice.
If possible, the substance causing the problem should be substituted by a safer one. For example, if it’s practicable to replace a paint containing isocyanates with an alternative that has no isocyanates but contains a safer non-toxic substance, then this would be an effective way of reducing the risk of asthma among the workforce. However, substitution may not always be possible and re-designing the work process to avoid exposure to the substance should be considered. For example, if employees have to handle chemicals, exposure could be avoided by introducing an automated handling system.
To meet the COSHH Regulations you need good controls and good practice. Effective control measures for airborne contaminants include local exhaust ventilation and enclosures. For example, in laboratory animal houses, open-top cages could be replaced by individually ventilated cages.
Where an occupation has been linked with a specific health condition, additional precautionary measures may also prove useful. For example, a review published by the University of Southampton found that welders were up to six times more likely to suffer from Pneumococcal pneumonia - a disease that usually affects very young individuals, the elderly and those with impaired immunity. Therefore, offering vaccination to individuals can prevent potentially fatal lung disease in this risk group.
Finally, as a last resort, breathing protection should be used. The HSE has a publication, Respiratory protective equipment at work: a practical guide. This deals with the selection and use of breathing equipment, and describes a step-by-step approach on the best type to choose.
The only types of breathing equipment that should be used are those that have been tested to the relevant European Standards and carry the CE mark plus the European Standards and performance category markings.
Under COSHH, the Control of Asbestos at Work Regulations (CAR) and the Control of Lead at Work Regulations (CLAW) - and the associated ACOPs - employees must have a test to make sure their breathing equipment fits properly. The HSE provides guidance on fit testing of respiratory protective equipment face pieces. Testing should be carried out by an accredited professional. You can get advice on this from the British Occupational Hygiene Society, which has a Directory of Occupational Hygiene Consultants.
Employers may have to measure levels of airborne contaminants in the workplace to make sure that WELs aren’t exceeded. You can get practical guidance on measuring exposure in the HSE’s publication, Monitoring strategies for toxic substances.
You can also get information and guidance on sampling techniques and methods for different substances in the HSE’s methods for the determination of hazardous substances.
For more in-depth advice on measuring the risks of exposure by inhalation, contact the British Occupational Hygiene Society.
Under the COSHH Regulations, employers must carry out health surveillance of employees who are, or who are likely to be, exposed to substances that are hazardous to health. Health surveillance helps employers detect problems at an early stage and reduce exposure to the substances responsible for the problem. It also allows the employer to determine whether its confined to one employee who had an existing problem, such as rhinitis or asthma, or more widespread. Here, carrying out an annual questionnaire may be useful.
For workplaces where employees are exposed to substances that are known to cause asthma, COPD or any other occupational lung disease, employers should carry out regular health surveillance of the workforce. It’s also a good idea to carry out pre-employment screening.
As part of COSHH essentials, the HSE has guidance notes on health surveillance for occupational asthma and health monitoring for chronic obstructive pulmonary disease. The TUC’s workSMART site gives employees information on health surveillance.
The HSE has free samples of health questionnaires that can be used where there’s a risk of occupational asthma. There are notes for the responsible person, an initial questionnaire and a follow-up questionnaire.
Educating and training employees
Under the COSHH Regulations, employers have a duty to provide employees who could be exposed to a hazardous substance with education, instruction and training on the possible risks to health and the precautions they should take. This should cover specific signs and symptoms to be aware of. Employees who are potentially exposed to asthmagens should be given information about the typical symptoms of asthma and the substances that are likely to cause it. They should also be told about the need to report symptoms which might indicate asthma. It should also be stressed to the employees that once someone has developed occupational asthma, it’s likely to be irreversible, and further exposure could increase its severity and possibly incapacitate them.
Early identification of respiratory problems is important. The workforce needs to be aware of risk factors, what symptoms to look for and how to report them, should they arise.
Developed in partnership with: