Asthma
Asthma is an inflammatory disorder of the bronchial airways which results in the airways becoming inflamed, muscles in the airways tightening and too much mucus being produced.
The symptoms of asthma include attacks of coughing, wheezing, shortness of breath and a tightening around the chest. Some sufferers become so debilitated that they cannot work again.
Most occupational asthma is caused by a worker developing sensitivity to a dust or chemical. Basically the body starts to think that the substance is harming them and sets off an immune reaction. Once a worker has been “sensitised” any exposure can bring about an attack. The symptoms sometimes develop immediately after exposure, but often symptoms appear several hours later, possibly at night.
There are also other irritants found at work which can cause asthma if a person already has a pre-existing history of asthma. These include chlorine, ammonia, and sulphur dioxide. Asthma can also be triggered by cold or tobacco smoke.
Occupational Asthma can be caused by inhaling any one of over two hundred substances. The most common of these are chemicals called di-isocyanates which are used in some foams and paints. However UNISON members are more likely to develop asthma through exposure to flour, dust, latex, glutaraldehyde, animal hair or urine, certain insects, wood dust and enzymes (in detergents).
Groups particularly at risk include catering workers, school and college technicians, nursing staff and cleaners. However any member exposed to any of the known sensitisers is at risk.
Because it is often difficult to know whether a person develops asthma as a result of contact at work, in the house, or elsewhere, it is not possible to say how many cases of occupational asthma there are every year. The Health and Safety Executive (HSE) estimates 1,500 to 3,000 new cases of occupational asthma each year, but this rises to 7,000 cases a year if you include asthma made worse by work.
Occupational asthma is the most frequently reported occupational respiratory disease in the UK and costs the economy up to 1.1 billion pounds a year.
However occupational asthma is easily preventable.
THE LAW
The Health and Safety at Work Act places a general duty on employers to protect workers health. In addition the Control of Substances Hazardous to Health Regulations (COSHH) spells out what they must do to reduce the risk from chemicals and other hazardous substances. There is also an Approved Code of Practice on controlling substances that cause occupational asthma.
These provide a legal framework that employers must act under. COSHH is a legal requirement and the Approved Code of Practice on asthma should be followed by employers if they are to be confident on meeting the requirements of COSHH.
What the regulations state is that if an employer uses any substance known to cause asthma, they should undertake a risk assessment which should identify the hazards, outline who might be harmed and how, evaluate the risks, see if exposure can be prevented or reduced, record the findings, and review the assessment and revise it if necessary. If the risk assessment shows any possible exposure they should look at whether they need to use that substance. If not, it should not be used or a less dangerous substance should be substituted for it. If it cannot be removed then it should be reduced to as low a level as is reasonably practical by either reducing its use, or if that is not possible by containing it. If exposure to this substance is still possible then the employer should introduce ventilation and extractor fans, and as a last resort, personal protective equipment such as face masks.
However there are a lot of substances that also have specific exposure standards. These are called maximum exposure limits (MEL) and occupational exposure standards (OES). 
 

A MEL is set for substances which will cause the more serious health effects (including asthma) and there is no known safe limit or it is not possible to keep within such a limit. An OES is set at the level which according to current knowledge is not likely to harm workers, and employers should reduce exposure to that level if they are to comply with the law. If a substance has an MEL employers must not just meet the level of the MEL but have to reduce the exposure as far as reasonably practical, or, better still, remove the substance from use if possible.
Safety representatives should not see OES or MEL levels as being “safe” and the aim should always be to remove exposure completely, or otherwise reduce exposure as far as is possible.
Information on the various occupational exposure limits are found in a guide which is produced every year by the HSE called EH40. Many of the substances that cause asthma have either an MEL or OES. Most dusts such as wood, flour, and cotton, are so dangerous that they are covered by a MEL and workers should not be exposed to them at all if possible. However even if a dust does not appear in the list of MELs or OESs, it is still subject to COSHH if present above certain concentrations. Further details are in the HSE booklet “Dust – General Principals of Prevention” (EH44). COSHH also states that there must be health surveillance of all workers exposed to a substance known to cause asthma. Many UNISON members who are exposed to flour, or other asthma causing dusts, are not offered this by their employer. Safety representatives should ensure that there is a proper health surveillance and record keeping system whenever there is the possibility of exposure to a dust or chemical known to cause asthma. The health surveillance system must be able to detect symptoms at an early stage as removal from exposure can lead to a complete recovery.
In addition, employers must provide information and training to all their workforce on any substances they use and keep the safety data sheets on these. They should also make them available to safety representatives on request.
Where Personal Protective Equipment is used, it should be as a last resort after all other solutions have been considered, and workers should be involved in discussions on what type of Personal Protective Equipment is appropriate for them.
Where a case of occupational asthma does arise, safety representatives should ensure that the employer immediately reviews their procedures and risk assessments.
EMPLOYMENT PROTECTION
Any person who develops asthma may be covered by the Disability Discrimination Act, and the employer should make suitable adaptations to ensure they are kept working without being exposed to any substance that may trigger an asthma attack.
Ideally the substance causing exposure should be removed. However, if that is not possible the work should be redesigned or the person re-deployed to a similar job where there is no possibility of exposure. But remember that if one case of asthma has arisen then just moving the person will not protect other workers who may be exposed.
If an employer does expose a worker to a known asthma causing substance, and they develop the disease, the employer may be liable for compensation. In addition, occupational asthma is a recognised industrial disease for industrial injuries benefit purposes.
MORE INFORMATION
UNISON has produced an information sheet on dangerous substances. This is available on the UNISON website http://www.unison.org.uk or from the Health and Safety Unit - e-mail healthandsafety@unison.co.uk or telephone 020 7551 1156.
The HSE also have an Asthma section on their website. Go to: http://www.hse.gov.uk/asthma The list of substances with exposure limits is on the main HSE website at: http://www.hse.gov.uk