Every year, nearly 13,000 deaths are associated with past exposure to hazardous substances in the UK workplace. Whether its root cause is chemicals, dust, or something else, the result is the same. With awareness rising around the negative consequences that hazardous substances can cause, it is important to remember that most of these ill health effects are avoidable. Throughout this article I will be discussing how using the correct control measures, procedures and emergency equipment can ensure these risks are nullified.

Throughout my career, I have witnessed all levels of hazardous substance management. From those companies with little to no understanding of the risks, to those that invest heavily in controlling and minimising exposure to chemicals. The key area that I have most commonly seen lacking is education and awareness of the substances. Even though it’s a legal requirement for companies to control hazardous substances and inform workers of the risks, controls and emergency procedures associated with the materials they use at work, there is still more work to do around education and awareness of hazardous substance usage.

“the key area most commonly seen lacking is education and awareness of substances”


Compliance with these regulations is often seen as a niche or difficult part of health and safety, but it makes a significant contribution to the large number of work-related ill health cases registered every year. While it can be difficult with more complex substances, achieving general compliance is just a case of taking it step by step. The first step is always to identify all the hazardous substances that you have on site; this can include chemicals, dust, cleaning substances and fuel. It may sound simple, but this is vital, as each of these substances will likely have different hazard classifications, meaning they will require different control measures and emergency precautions.

The hazard classifications of substances can vary widely but should all be supplied in the same format. Thanks to the Classification, Labelling and Packaging (CLP) regulations, all formal classifications must be in the form of “Hazard Statements”.

“before resorting to the use of PPE, there must be an effort made to prevent exposure to the substance”

These are displayed with a code and associated statement, e.g. H314 – causes severe skin burns and eye damage. This information should be readily available on the substances Safety Data Sheet (SDS), which again, comes in a standardised format to ensure they provide all that is needed to correctly risk assess its use. To comply with the REACH (registration, evaluation, authorisation and restriction of chemicals) regulations, SDS must come with 16 defined sections, outlining all the necessary information to evaluate, classify and control the material it regards. Using this information, you can then undertake your COSHH risk assessment for the use of the substance, allowing the necessary controls to be put in place. These controls can take many different forms, from using Personal Protective Equipment (PPE) to make a physical barrier between the skin and substance to extraction systems that remove the hazard at source.

Hierarchy of control

The control of hazardous substances follows the “hierarchy of control,” similar to many other areas of health and safety. This means that before resorting to the use of PPE, there must be an effort made to prevent exposure to the substance, therefore, negating further assessment. The first to be considered should always be elimination of the hazard. Is there a way in which the task can be modified or changed to remove the hazardous substances altogether? For example; using pre-coated materials instead of painting, or riveting instead of welding.

If the material cannot be eliminated, then its substitution must be considered, exchanging it for an alternative that has a lesser hazard classification. These two initial steps are vital; reducing the number and quantity of hazardous substances in the workplace should be our ultimate goal. It becomes of particular importance when using those substances classified as carcinogenic (cancer causing), mutagenic (capable of changing DNA) or reprotoxic (toxic to the reproductive system, both male and female). These groups of substances are capable of causing such dramatic and life changing effects, that they must be controlled as much as possible. The best way to do this is to not use them at all.

However, many of the substances that are classified this way will need to be used. This is mainly due to them being highly effective at the task they were designed for. One key example of this is dichloromethane, an extremely effective solvent that is used in many paint strippers. While many efforts have been made to remove this chemical from UK workplaces, it has proven itself imperative in many industry sectors. The possibility of swapping it out for another, less volatile chemical, was made impractical by the impact its absence would have on the quality and timescales of the work. In this case and many others, substances cannot be eliminated or substituted, so high-level controls must be put in place to prevent the user and those nearby from being exposed at a dangerous level.

Once the control of a substance is required, there are many different factors to consider, each of which can be affected by the nature and chemistry of the substance that is being used. Much of this information is easily accessed, with many suppliers providing at least some basic information on the protection needed. This can include recommended PPE such as gloves, respirators and eye protection.

The last line of defence

Gloves and respirators are two types of protective equipment that are dependent on the chemistry of the product that is being used, it is not a case of one size fits all. Respiratory Protective Equipment (RPE), if filter based, will be designed to protect against a particular group of chemicals. Whether it is for organic vapours, inorganic vapours, acid gas or particulates, you must select the correct type, as each only protects against the aforementioned substance. This selection of inappropriate filters is a very common error, one which I have witnessed in many companies across multiple sectors. Selecting the wrong filter for a mask will not only result in an under protected user, but it will also have given them a false confidence, which may in some cases be more dangerous. If operatives believe they are protected and safe, they will spend more time in risky situations. If you ever find yourself in doubt about the type of mask that you or a member of staff may need, either seek guidance from a manufacturer, the supplier of the chemical or use a combination filter, designed to protect against more than one type of substance.

Similarly, gloves can also be difficult to select. There appears to be a common misconception that blue nitrile gloves will protect against all hazardous substances, having encountered this across multiple industries. Nitrile gloves are a good middle ground, offering sufficient protection against many substances while retaining a level of dexterity, making them comfortable to wear. However, there are many substances that will not be protected against by wearing nitrile gloves. Unfortunately, there is no one glove that will protect against all hazardous substances.

This means that as a simple matter of good practice, you should always have a selection of glove materials to use, whether this is butyl, PVA, PVC or Viton. Safety data sheets will often give an indication of the type of gloves that can be used, alternatively, glove matrices are available from many leading PPE manufacturers to help. Something that should also be taken into account when selecting PPE is the task that is going to be
done. Many tasks may require heavy duty gloves to prevent splitting or abrasion, while welding requires heat resistance. All these aspects must be considered when undertaking your COSHH risk assessments. One item to always remember is to, as far as possible, avoid latex gloves. An increasing number of the population is allergic to latex and as a sensitising material, this number will only grow over time.

Be prepared

Even with all the levels of protection that you put in place for the use of a substance, unfortunately, there will always be accidents and incidents involving them. This means that we must always prepare for these eventualities, ensuring that swift and effective action can be taken to combat any potential ill health effects. When considering hazardous substances, an emergency should include any situation that will expose operatives to an excessive or dangerous level of the substance, including a fire, spillage and of course first aid.

Due to the nature of many chemicals, they will react in ways that could surprise those who are unfamiliar with them. For example, in a fire, you should always know what substances you have and where they are located as items like aerosol cans can explode when heated and should therefore be kept cool. Oils and other hydrocarbons will float on water, meaning that if you try and use a water-based extinguisher it is more likely to exacerbate and spread the fire than put it out. You should always understand the firefighting needs of the products you use and if possible, create an index showing their location on site, to help the emergency services if they are required.

Act fast

A first aid situation with a hazardous substance is an occurrence that noone wants to find themselves in, the ability to react quickly often being the difference between complete and incomplete recovery. With eye-wash, showers, burns treatment and neutralising solutions, there are many ways to treat over exposure to a hazardous substance, so long as you understand the type of substance that caused the ill health. Neutralising solution for example can be key in the treatment of acid and alkali burns, which get more serious the longer the substance is still active. Hydrofluoric acid is used in many industrial processes, including glass etching and metal cleaning. Being one of the most potent mineral acids and one of the few that can etch glass, it is highly effective in these roles, so is still found in industry. While it is nearly always stringently controlled, unintentional exposure can occur. At this point, the highly toxic and corrosive nature of this chemical can cause life changing injuries in a short amount of time. The best way to treat the person involved is to use a neutralising agent such as calcium gluconate, which neutralises the acid and limits the damage it can cause. The importance of reacting quickly cannot be overstated, if these injuries are left untreated even until an ambulance arrives or the person is seen at hospital, the outcomes would be far more severe.

Eyewash stations

While calcium gluconate is maybe a touch niche, there are some very common and easy to use items that can be used in the treatment of hazardous substance injuries, the notable one being eye wash stations. This simple tool has been responsible for saving the sight of many workers, both from chemical splashes and particulates alike. Corrosive materials will have the same effect on eyes as they do skin, causing burns and ocular lesions should they make contact. However, it is not just these corrosive chemicals that can cause damage to the eyes, with many substances being ocular irritants.

There are many particulates that can get into your eyes and cause irritation or scratches to the surface of the eye. If you include all the potentially hazardous substances that can cause damage to the eyes, almost all workers within the UK will at some point be exposed to one. It is therefore important for all workplaces, even office environments, to ensure that eyewash is available. The stations can come in many shapes and sizes to suit the situation. In many cases, bottles of eye wash solution with an applicator will be sufficient to cope with the situation. However, in industries and areas with a high risk of eye/chemical contact, a more immediate solution may be required. A station that is designed to drench and flush out the area for a prolonged period will be of more use, to either remove the entirety of the substance from the eyes, or to dilute its concentration to a point where it is no longer hazardous.

This can be a key element in treating hazardous substance over exposure, drench and dilute. If you have the facilities to overwhelm the substance with water, this can be a great tonic. All hazardous substances will have concentration gradients that govern their toxicity, if you can bring this concentration down, the hazardous properties will also diminish. This does have the obvious exception of materials that react violently with water such as the alkali earth metals.

Emergency showers

Emergency showers can be just as valuable for the same reason, just treating the skin and body rather than the eyes specifically. Much like the eye wash, it is designed to drench the area and flush out any unwanted substances. When working with strong acids and alkalis such as on a plating line, emergency showers can quite literally become a life saver. Should an operative be exposed to a chemical that can cause large-scale damage very quickly, removing that substance is a necessity. However, while they are designed to help in an emergency, showers can in fact themselves become hazardous. This is due to the possibility of stagnant water, which can act as breeding ground for biological agents which are also governed under the COSHH regulations. Bacteria such as Legionella and Leptospirosis can contaminate stagnant water tanks and showers should they not be flushed, treated or tested regularly. Both bacteria can lead to serious illness that may require hospitalisation.

This will often depend on whether the shower is plumbed in or not, showers that are fed from tanks are more likely to become contaminated if not maintained correctly. However, with correct treatment and regular flushing, emergency showers can be a vital piece of response equipment.


Maintenance is key with all items of emergency and protective equipment. One of the common failings in health and safety is the implementation of controls that are then not maintained. All levels of control, from PPE to extraction systems, if left to deteriorate, will become less effective. I have attended many sites where they have failed to keep on top of the 14-month maintenance schedule for their local exhaust ventilation systems. This meant that they had slowed down and were not achieving the draw rate that they promised, leaving much higher levels of airborne dusts in the area than expected. This is particularly dangerous as many companies use these systems to justify the removal of masks and respirators. If people believe they are protected when they are not and do not use the correct PPE, it can only result in ill health and injury. If you are issuing RPE, ensure that operatives understand if they are using disposable masks they must be changed after each use, or for non-disposable that the filters will have a defined lifespan and must be changed regularly.


Of course, with all of this in mind, in my opinion the single biggest factor in the success of your control of substances hazardous to health is awareness. Correct training and instruction of operatives using these substances is imperative. If they don’t fully understand the hazardous nature of the products, they won’t understand how important it is to protect themselves and others. While PPE shields just the operator, the incorrect use of engineering or emergency controls will affect others in the local area. Just as many people have now become aware of the negative effects of passive or secondhand smoking, a high percentage of those affected by occupational lung disease were not those directly using the substances. Particulates, fumes and vapours can carry a surprising distance if there is not sufficient ventilation or intervention. In 2018/19, there were 18,000 new cases of breathing or lung problems caused or made worse by work.

Preventing exposure to hazardous substances in the workplace is a crucial factor in reducing the high numbers of both acute and chronic work-related ill health in the UK. By understanding and implementing both our legal and moral duties in this area, the UK workplace will soon become safer, healthier and stronger.