Risk Assessment for Working with Hazardous Substances on Irish Construction Sites

How do you carry out a risk assessment for hazardous substances on an Irish construction site?

Construction sites in Ireland use a wide range of hazardous substances, from the obvious ones like solvents and paints to the less obvious ones like silica dust generated by cutting concrete and wood dust generated by sawing timber. Many contractors have reasonable control measures in place for the obvious hazards, but the less visible ones, particularly the dusts and vapours that workers breathe in every day, are often poorly managed.

The risk assessment for hazardous substances is a specific legal requirement in Ireland, separate from the general risk assessment required by the Safety, Health and Welfare at Work Act 2005. It is governed by the Safety, Health and Welfare at Work (Chemical Agents) Regulations 2001 (as amended), and it has specific requirements that go beyond the general risk assessment process.

This post covers the legal requirements for hazardous substance risk assessment in Irish construction, the key hazardous substances that construction contractors need to assess, and the practical steps for carrying out a compliant COSHH assessment.

The Legal Basis: Chemical Agents Regulations 2001

The Safety, Health and Welfare at Work (Chemical Agents) Regulations 2001 (S.I. No. 619 of 2001) implement the EU Chemical Agents Directive in Ireland. They apply to any workplace where workers may be exposed to chemical agents, including construction sites.

The Regulations require employers to carry out a risk assessment of any work activity that may involve exposure to chemical agents. The risk assessment must consider the nature of the chemical agent, the level, type, and duration of exposure, the circumstances of the work, and the occupational exposure limit values (OELVs) set for the substance.

If the risk assessment shows that there is a risk to health, the employer must take preventive and protective measures to eliminate or reduce the risk, following the hierarchy of control: eliminate the hazard, substitute a less hazardous substance, engineer out the hazard, use administrative controls, and provide personal protective equipment as a last resort.

Key Hazardous Substances on Irish Construction Sites

Silica dust: Silica is found in concrete, mortar, stone, brick, and many other construction materials. When these materials are cut, ground, drilled, or polished, respirable crystalline silica (RCS) dust is generated. RCS is a serious health hazard that can cause silicosis, a progressive and irreversible lung disease, as well as lung cancer and other respiratory conditions. The occupational exposure limit for RCS in Ireland is 0.1 mg/m³ as an 8-hour time-weighted average.

Wood dust: Wood dust is generated by sawing, sanding, routing, and machining timber. Hardwood dust is classified as a carcinogen and is associated with nasal cancer. Softwood dust can cause occupational asthma. The occupational exposure limit for hardwood dust in Ireland is 3 mg/m³ as an 8-hour time-weighted average; for softwood dust it is 5 mg/m³.

Isocyanates: Isocyanates are found in two-pack polyurethane paints, spray foam insulation, and some adhesives. They are one of the most common causes of occupational asthma in Ireland. Once a worker is sensitised to isocyanates, even very low levels of exposure can trigger a severe asthma attack. The risk assessment for isocyanate-containing products must consider the method of application, the ventilation of the work area, and the respiratory protective equipment required.

Solvents: Solvents are found in paints, varnishes, adhesives, and cleaning products. Many solvents are flammable and can cause narcotic effects at high concentrations. Some solvents, such as benzene and trichloroethylene, are carcinogens. The risk assessment for solvent-containing products must consider the vapour pressure of the solvent, the ventilation of the work area, and the personal protective equipment required.

Cement: Wet cement is a serious skin hazard. It contains calcium hydroxide, which is highly alkaline and can cause severe chemical burns if it remains in contact with the skin for extended periods. Cement also contains chromium compounds, which can cause allergic contact dermatitis. The risk assessment for cement work must consider skin protection measures, including the use of waterproof gloves and barrier creams.

Lead: Lead is found in older buildings, particularly in paint applied before the 1970s. Workers involved in demolition, renovation, or maintenance of older buildings may be exposed to lead dust and fumes. Lead is a cumulative toxin that can cause serious neurological damage. The risk assessment for work involving lead must consider the method of work, the ventilation of the work area, and the personal protective equipment required.

Asbestos: Asbestos is found in many older buildings, particularly those built before 1980. It is a serious health hazard that can cause mesothelioma, lung cancer, and asbestosis. Before any work begins on a building that may contain asbestos, a survey must be carried out to identify and assess the condition of any asbestos-containing materials. Work involving asbestos must be carried out by licensed contractors using specific control measures.

How to Carry Out a COSHH Assessment

A COSHH assessment for a hazardous substance on a construction site should follow these steps:

Step 1: Identify the substance. Obtain the Safety Data Sheet (SDS) for the substance from the manufacturer or supplier. The SDS contains information about the hazards of the substance, the occupational exposure limits, the control measures required, and the personal protective equipment needed.

Step 2: Identify who may be exposed. Consider all workers who may be exposed to the substance, including those who are not directly using it but who may be in the vicinity when it is being used.

Step 3: Evaluate the risk. Consider the level, type, and duration of exposure, and compare it to the occupational exposure limit value for the substance. If exposure is likely to exceed the OELV, or if the substance is a carcinogen or sensitiser for which no safe level of exposure can be established, the risk is significant and control measures must be implemented.

Step 4: Implement control measures. Follow the hierarchy of control: eliminate the hazard if possible, substitute a less hazardous substance, engineer out the hazard (for example, by using wet cutting methods to suppress silica dust), use administrative controls (for example, by limiting the time workers spend in the hazardous area), and provide personal protective equipment as a last resort.

Step 5: Record the assessment. The COSHH assessment must be written down and kept available for inspection by the HSA. It should include the name of the substance, the work activity, the workers exposed, the control measures in place, and the personal protective equipment required.

Step 6: Review the assessment. The COSHH assessment must be reviewed whenever there is reason to believe it is no longer valid, or when there has been a significant change in the work activity or the substances used.

Personal Protective Equipment for Hazardous Substances

Personal protective equipment (PPE) is the last line of defence against hazardous substances, not the first. However, it is often the most visible control measure on a construction site, and it is important that the right PPE is selected and used correctly.

For respiratory hazards such as silica dust, wood dust, and isocyanates, the appropriate respiratory protective equipment (RPE) must be selected based on the nature of the hazard and the level of exposure. A simple dust mask (FFP1 or FFP2) may be appropriate for low-level dust exposure, but for higher levels of exposure or for carcinogenic dusts, a higher-specification respirator (FFP3 or a powered air-purifying respirator) may be required. RPE must be face-fit tested to ensure it provides an adequate seal.

For skin hazards such as cement and solvents, the appropriate gloves must be selected based on the nature of the hazard. Nitrile gloves provide good protection against many solvents and cement, but the specific glove type must be selected based on the SDS for the substance.

Conclusion

A COSHH assessment for hazardous substances is a specific legal requirement for Irish construction employers, separate from the general risk assessment required by the Safety, Health and Welfare at Work Act 2005. The key hazardous substances that construction contractors need to assess include silica dust, wood dust, isocyanates, solvents, cement, lead, and asbestos. If you are unsure whether your COSHH assessments meet your legal obligations, contact Safety Check for a review.