Hazardous substances and dangerous goods

Hazardous substances are chemicals that can harm human health. While it might be obvious that some substances, such as acids or poisons, can cause harm, some health effects may not be so readily apparent. For example, in some cases dusts or vapours can also be hazardous substances.

Substances that cause skin irritation, allergies, cancer, birth defects, genetic mutations, and other health effects are also classified as hazardous substances. Health effects may not be immediate and may occur over a long time period. A hazardous substance may be a simple chemical or it may be a mixture of several chemicals.

Chemical hazards are not limited to those substances obtained from a supplier and delivered in a labelled container with an MSDS. Industrial processes such as welding or grinding may cause toxic fumes or dusts. Toxic atmospheres, or atmospheres without enough oxygen to sustain life, may develop in confined spaces or inadequately ventilated spaces.

Examples of some potentially hazardous substances include:

paints
drugs
cosmetics
cleaning chemicals
degreasers
detergents
gas cylinders
refrigerant gases
pesticides
herbicides
diesel fuel
petrol
liquefied petroleum gas
welding fume.

Some hazardous substances are also classified as dangerous goods. Dangerous goods are those substances or articles with an immediate risk to health or safety. This includes physical risks such as flammability or corrosion

For a hazardous substance to have an effect it has to make contact with or enter the body – the way this occurs is called a route of entry. The main routes of entry are:

swallowing – for example from hand contamination or food contact
breathing in (inhalation) of atmospheric contaminants
skin or eye contact – such as contact with dust on surfaces, splashes to the skin or eyes.

Some substances are so poisonous that swallowing a small amount will cause harm. Swallowing can occur from airborne dusts and sprays, or during eating or smoking from unwashed hands or contaminated food.

There are three basic physical forms:

solids (including dusts, fumes and smoke)
liquids (including mists and vapours)
gases (including vapours).

The physical form of a substance often depends on how it has been generated or how it is being used.

Dusts

Dusts are generally formed by grinding, abrasion, or crushing of larger solids. They can be generated by processes such as grinding, sanding or polishing. Examples are asbestos, coal, cotton, wood and wheat dust. Most industrial dusts are capable of being drawn into the human respiratory system (ie breathed in).

Whether dust gets into the body depends on the size of the dust particle. The two terms used are inspirable and respirable. Inspirable dust includes larger particles that tend to lodge in the upper respiratory tract. Respirable dusts are tiny particles that become lodged deep in the lungs.

Some dusts can also be a fire or explosion hazard. In form of a dust some substances become very reactive.

Fumes

Fumes are fine, solid, dust particles that are formed when metal is melted and some of the molten metal turns to vapour (for example by processes such as MIG welding or stick welding). As these metal vapours cool they condense into fumes.

Fume particles are so small they can be carried deep into the lungs. A single exposure to the fumes of metals, such as zinc oxide, copper oxide or magnesium oxide, can cause metal fume fever. Metal fume fever has symptoms that are very like a cold or the flu, except that the symptoms often clear up when employees are removed from the area where exposure is occurring.

Fumes can arise from molten metals such lead baths and metal casting. Welding is particularly hazardous when the metal has coatings such as lead or cadmium.

Smoke

This results from the incomplete burning of materials. Smoke consists of soot, liquid droplets and ash. Smoke also occurs during processes such as spot welding or oil quenching. Smoke particles are usually smaller than dust particles and can easily move deep into the lungs. Carbon particles in smoke can have other chemicals absorbed on to them that may cause lung irritation.

Liquids

Liquids may cause poisoning and/or physical injury if they are swallowed. Some can burn your skin (acute local effect). Many other liquids used in industry, including pesticides, solvents, paints, cutting fluids/oils and liquid fuels are also hazardous substances because they are easily absorbed through the skin into the blood. They can be absorbed more quickly if your skin is weakened in some way – for example if your skin is cracked, reddened, broken or very dry.

It is important to prevent spillage of liquids since they can rapidly spread. Other risks from liquids arise because they easily change to aerosols and vapours that move even more rapidly through the air. Flammable liquids can be very dangerous if spilt, since flammable vapours result and can ignite explosively.

Liquids that change easily into gases (eg petrol, alcohol) can spread widely through a workplace if the container has no lid or seal. These vapours can cause both exposure and fire hazards.

Vapours

Vapours can form when a liquid evaporates – ie. moves into the air as a gas. Vapours can be inhaled easily. Vapours are even more hazardous in small enclosed spaces; they can form explosive atmospheres and easily reach toxic levels.

Liquids are more likely to become vapours (vaporise) when temperatures increase and/or when atmospheric pressure decreases. Liquids that vaporise easily at room temperature are said to have a high vapour pressure and low boiling point.

High vapour pressure/low boiling point liquids are also known as volatile liquids. The more volatile a liquid, the faster it will evaporate. It is difficult to control the risks for volatile liquids because they are so likely to change to vapours. Vapour from flammable liquid can be explosive.

Mists, fogs and aerosols

Mists, fogs and aerosols consist of fine liquid droplets suspended in the air. Mists can be formed in the workplace when machine and lubricating oils are used (for example oil mists from cutting and grinding operations and pesticide mists formed from spraying operations). Steam cleaning spray jets can also produce mists.

Aerosols are often generated when liquids are handled too vigorously or sprayed. Usually the size of the droplets in an aerosol are so small that they remain suspended for long enough to be widely dispersed.

Gases

Gases can be a hazard because they disperse in the air very quickly. Air is a gas made up mainly of nitrogen and oxygen with a small amount of other gases. Gases can be hazardous to your health if they are toxic or take the place of oxygen needed to breathe.

Human lungs absorb oxygen, but also can absorb other gases easily. These gases enter the blood stream and are carried directly to other parts of the body with rapid effects. Carbon monoxide is an example of a gas that readily enters the blood stream. This can be generated by vehicle engines such as forklift trucks and is a problem in enclosed spaces such as stores.

Non-toxic gases can be hazardous if they are allowed to build up to the point that they are taking up the space that would normally be occupied by the oxygen needed to stay alive. This will cause death by asphyxiation. Some gases have no detectable odour or colour thus adding an increased risk because the presence of the gas cannot be detected.

Hazardous substances that are used in the workplace without proper exposure controls may harm the health of all those exposed. These adverse health effects can be immediate, or appear days, weeks, months or even years after exposure.

Some hazardous substances produce few, if any, obvious symptoms until the onset of illness. For example, in the case of asbestos exposure, symptoms of illness usually do not show up until 20 or 30 years later.

Some other chemicals can have both short-term (perhaps coughing) and long-term symptoms (such as cancer) that do not appear until years after exposure. For example, some solvents can produce headaches, nausea and vomiting soon after exposure and increase the risk of cancer in the long term.

Typical symptoms which can indicate exposure to a hazardous substance are:

eye irritation
skin rashes
difficulty in breathing/shortness of breath
headaches, confusion, fatigue
cold or flu symptoms.

However some very serious chemical exposures have no warning symptoms.

The effects of a hazardous substance depend on:

the toxicity – the capacity to cause harm
the level of exposure to the chemical – the dose the body actually receives
individual susceptibility.

The risk of a hazardous substance is determined by a combination of dose and toxicity. See definitions for some definitions relating to hazardous substances. Also see more information for more details on the type of hazardous substances.

The disability sector is varied and diverse. Chemicals may be encountered in a range of work locations including offices, day care programs, client’s homes and disability enterprise workplaces. Not all these chemicals are classified as hazardous according to the legislation but still may have the propensity to affect an individual due to specific sensitivities. The label of the substance should indicate if the substance is potentially hazardous. However, general risk management principles apply to all chemicals and to Hazardous Substances in particular.

Legal obligations

Disability Service providers are required to do the following related to hazardous substances:

obtain a Material Safety Data Sheet (MSDS) from the supplier of the hazardous substance or dangerous goods either before, or on the first occasion, on which the substance is supplied. This mirrors the supplier’s duty to provide MSDS. These MSDS may be transmitted in electronic form. Where an MSDS has not been provided, it may be requested from the manufacturer or importer. The MSDS of a hazardous substance will assist risk assessment of the use of the hazardous substance (or dangerous goods) and any necessary controls to be established in the workplace.
Ensure that the MSDS is accessible to all employees likely to be exposed to the substance either in paper or computerised form;
Ensure that employees read and understood the contents of the MSDS
Ensure that all containers of hazardous substances are appropriately labelled
Ensure that any container into which a hazardous substance is decanted is clearly labelled with product name and any relevant risk and safety phrases if the product is to be used within 12 hours and with a full label if to be held longer.
Maintain a register of hazardous substances and dangerous goods used or produced in the workplace. ADEs may prefer to use a chemical storage register depending on type and amount of chemicals used.
Ensure appropriate placarding of tanks or bulk stores containing dangerous goods
Ensure that risk assessments are undertaken and risk controls implemented. At a minimum risk controls must be equivalent to the handling and storage requirements listed in the material safety data sheet.
Ensure that an induction and training program is implemented which incorporates the following elements:

(a) The labelling of containers of hazardous substances, the information that each part of the label provides and why the information is being provided.

(b) The availability of MSDS for hazardous substances, how to access the MSDS, and the information that each part of the MSDS provides.

(c) Information about hazardous substances to which employees are or may be exposed in the course of their work. Information should include the nature of the hazards, risks to health arising from exposure, the degree of exposure and routes of entry of the hazardous substances into to the body. This includes information on the forms of hazardous substances including dusts, fumes and other atmospheric contaminants.

(d) The risk assessment process and how the employee can contribute.

(e) The work practices and procedures to be followed in the use, handling, processing, storage, transportation, cleaning up and disposal of hazardous substances.

(f) The measures used to control exposure to hazardous substances, including any information that the employee requires for the correct use and maintenance of control measures.

(g) The proper use and fitting of personal protective equipment.

(h) The procedures to be followed in case of an emergency involving hazardous substances or dangerous goods, including any special decontamination procedures to be followed.

(i) First aid and incident reporting procedures to be followed in case of injury or illness.

(j) The nature of, and reasons for, any monitoring required and access to the results of monitoring.

(k) The nature of, and reasons for, any health surveillance required in order to detect the effects of exposure to a hazardous substance.

(l) The employees’ rights to be advised of the intention to use a new hazardous substance where they are likely to be exposed in the course of their work and the right to be consulted in the process of risk assessment of a hazardous substance.

(m) Employees’ rights and obligations in relation to health surveillance.

(n) Duties under the OHS Regulation of suppliers, employers and employees.

The amount of detail and extent of training required will depend on the nature of the hazard associated with the work activity and the complexity of the work procedures and control measures required to minimise the risk of exposure. In this regard, the risk assessment process provides important guidance.

All training should be reviewed on a regular basis and records maintained on training conducted and the contents of such training.

Risk Management and Hazardous Substances

Under the Occupational Health and Safety Act NSW 2000 (OHS Act) and Occupational Health and Safety Regulation 2001 (the Regulation) employers must ensure the health, safety and welfare of employees in relation to the use of hazardous substances.

Components of Risk Management – Reference Source ‘WorkCover NSW Hazpak Guide’

IDENTIFY – the potential exposure to hazardous substances whilst undertaking work tasks
ASSESS – the risk, the nature and severity of the potential health effects and the degree of exposure that could occur i.e. what injury can occur to the person. You will then come up with a risk ranking
CONTROL – once you have completed the assessment, you need to identify controls or measures to either eliminate the risk or reduce it to a low as reasonably practicable (ALARP)
REVIEW – controls and procedures, where manual handling is a component of ongoing care. Refer to Clause 12 OHS Regulations

If the inspection of the work shows that any risk can be, or is already, controlled in accordance with the MSDS (or the equivalent information about precautions for use and safe handling), the risk assessment is complete and no further assessment is needed.

For end use products, the MSDS should provide sufficient information on control measures, such as appropriate personal protective equipment (PPE). Examples of end use products are paints, pesticides, and adhesives.

For these simple and obvious risk assessments, the employer is required to note only the completion of the assessment in the register. No further report or record is required.

For some work a more detailed risk assessment may be necessary. These situations include those where either of the following apply:

there is uncertainty about the degree of risk
there is a significant risk to health, for example, exposure to a hazardous substance may be high and/or the nature of the health hazard is serous (this is particularly relevant for a listed carcinogen or a substance containing a listed carcinogen)
more complex chemical processes and/or exposures are involved.

A more detailed risk assessment may include obtaining additional information about health hazards, a thorough evaluation of the work to determine exposures (including atmospheric monitoring or biological monitoring) where appropriate), and examination or testing of existing control measures. In such cases, the OHS Regulation requires a written report to be prepared.

Responsibility for ensuring a risk assessment is carried out lies with the employer (or self-employed person). It is anticipated that the assessment will usually be done by a supervisor or manager of the workplace, in cooperation with the relevant employees.

The assessment must be undertaken in consultation with the employees and their representatives. A person carrying out an risk assessment should have sufficient knowledge and skills to evaluate the health risks to employees arising from operations involving hazardous substances in the workplace. A simple risk assessment would require at least an ability to interpret an MSDS.

A more complex assessment may require the assistance of relevant professionals, for example an occupational hygienist, with elements of an assessment that require special expertise.

Consultation between management, workers, clients and, if appropriate, their families or advocates is an important part of the hazard identification process.

Eliminate or control the risks. Ensure that work practices are designed to eliminate risk and if this is not possible the hierarchy of controls should be considered.

The Hierarchy of Control – ‘as low as reasonably practicable’

There are six ways to deal with hazards or control risks to health and safety

Eliminate - the hazard or risk e.g. using a physical process rather than a chemical process to clean an object, using clips, clamps or bolts instead of an adhesive, purchasing supplies of a material in a ready cut and sized form rather than carrying out a dust producing cutting process on site.
Substitute - substitute the substance or process for something that gives rise to a lesser risk e.g. replace a chlorinated degreasing solvent with a detergent, use a water-based pain in place of an organic solvent-based pain, use a substance in paste or pellet form rather than a dusty powder, applying paint by brush rather than aerosol.
Isolation – isolate the hazard, separate the hazard in time or space from the person at risk e.g. the remote operation of a process, the use of a closed work system such as a glove bag, which contains the substance within the bag and protects the employee from the substance.
Engineer – plant or process that minimise generation of a hazardous substance, suppress or contain the hazardous substance of limit the area of contamination in the event of spills or leaks e.g. enclosure or partial enclosure, local exhaust ventilation, vapour barriers, process automation.
Administration – safe work practices such as use of warning signs, reduce period of exposure by limiting access, rotation of staff, regular cleaning of work areas and removal of waste, prohibiting eating, drinking and smoking in contaminated areas, vacuuming dust, keeping lids on containers when not in use, facilities for decontamination of work clothes.
Personal protective equipment - this should not be the only control used unless it is impracticable to implement any of the above. Staff must be trained in the limitations, correct selection, application, storage etc of the equipment.

Chapter 7 of the OHS Regulation specifies measures to be taken for the following processes:

spray painting
abrasive blasting
welding
electroplating
molten metal
lead processes and lead risk work.

Consult the OHS Regulation for details.

A potentially unknown specific risk which may arise for support workers, exists when they are working with clients who are receiving cytotoxic drug therapy. A summary of issues and control strategies has been prepared.

Ongoing monitoring and review is an integral part of risk management. After applying controls to eliminate or reduce identified hazards, it is important to assess their effectiveness. Some controls might create other, unforseen hazards. It is important to continue to consultation with everybody involved.

You must review your risk assessment if:

there is evidence that it is no longer valid
an illness or injury occurs
a significant change occurs in work practices or procedures to which the risk assessment relates.

Emergency Procedures:

In spite of the implementation of all practicable control measures, a leak, spill or uncontrolled release of a hazardous substance could still occur. Established emergency procedures, procedures for safe disposal of the substance and sufficient suitable personal protective equipment should be used, where appropriate, to enable the source of the release to be safely identified and repairs made. All persons not directly concerned with the emergency should be excluded from the area of contamination. Consult the relevant MSDS for advice.

Employee Responsibilities:

Employees have a responsibility to maintain safe work practices to the extent that they are capable. This is specifically addressed in NSW occupational health and safety legislation and is dependent on adequate induction, training and supervision by the employer.

Employees should therefore use the control measures in the way that they are intended to be used, and in particular should carry out the following:

(a) Cooperate with their employer in performing the risk assessments of hazardous substances in the workplace.

(b) Participate in suitable induction and training programs.

(d) Wear, in a proper manner, the personal protective equipment provided.

(e) Store personal protective equipment in the accommodation provided when it is not in use.

(f) Remove from their person any protective equipment that could cause contamination, and wash before eating, drinking or smoking.

(g) Practice a high standard of personal hygiene, and make proper use of the facilities provided for washing, showering or bathing and for eating and drinking.

(h) Report promptly to their employer, through their supervisor, any defects discovered in any control measure, device, facility, label or item of personal protective equipment that may affect compliance with the provisions of the OHS Regulation.

(i) Cooperate with their employers in the conduct of appropriate monitoring or health surveillance programs that arise from risk assessments.

References

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