​What are the typical health hazards on a construction site?

Common respiratory health hazards on construction sites include:

• Silica dust
• Wood and other dusts
• Asbestos
• Welding and soldering fumes
• Diesel exhaust fumes
• Bitumen/asphalt fumes
• Legionella and other biological agents
• Solvents used in paints, glues or other surface coatings
• Isocyanates, epoxy and other resin vapours and mists

Other substances, like lead, can cause ill health effects, such as organ damage and blood poisoning, and the substances that cause the most skin health problems are wet cement, epoxy resins and hardeners, acrylic sealants, bitumen or asphalt, solvents, petrol, diesel, oils and greases, degreasers, descalers and detergents.

There are also many physical hazards that can lead to ill-health, for example noise, vibration, heat and light, and manual handling and ergonomic issues.

What are the common ill-health effects from working on a
construction site?

Respiratory problems are very common amongst construction workers. These range from minor or temporary symptoms like respiratory tract irritation and rhinitis (runny nose) and metal fume fever, through to chronic sensitising conditions such as bronchitis and asthma – which once fully developed is irreversible – through to other also serious, life-limiting and sometimes fatal conditions, including various lung and nasal cancers, an increased susceptibility to pneumonias, pulmonary fibrosis (eg. asbestosis and silicosis), pulmonary oedema (fluid on the lung), and chronic obstructive pulmonary disease (COPD) which describes a number of breathing problems where there is damage to the breathing tubes and air sacs within the lung (chronic bronchitis and emphysema are common types of COPD).

Most construction workers are also at risk of skin diseases including contact dermatitis and skin cancer, noise-induced hearing loss, hand-arm vibration syndrome, and musculoskeletal disorders, in particular back problems.

Many of these chronic conditions don’t manifest until many years after exposure to the hazard, or they only gradually worsen, and so are not immediately associated with their workplace causes.

This is not an exhaustive list of health risks; there are other respiratory and skin conditions, as well as many less common but just as serious diseases (eg. blood-borne diseases like Hepatitis A, B & C, HIV, Weil’s disease, E.coli infection etc from biological hazards which can contaminate sites).

How many people die from ill health caused by their work?

About 13,000 people die every year in the UK from diseases caused by the work that they do, or used to do.   (Last year, in comparison, 148 people died from accidents at work.) 99% of deaths caused by work can be attributed to ill-health, and 1% to poor safety.

• 5000 of these work-related annual deaths are caused by exposure to asbestos fibres.
• Over 500 construction workers are estimated to die in a year from exposure to silica dust.
• The latest research suggests that around 4000 COPD deaths every year may be related to work exposures. (Smoking is the main cause of COPD, but smoking in combination with exposure to hazardous substances in the workplace increases the risk, so the causes can be blurred.)

Which construction trades are at most risk?

There are lots of different construction trades, and they all face a combination of different hazards and levels of risk.

Any worker involved in maintenance, refurbishment or demolition of premises built before 2000 is at risk of inadvertent exposure to asbestos, but those at particularly high risk are Licensed Asbestos Removal Workers, Demolition Operatives, Electricians, Glaziers, Heating/Plumbing Engineers, Painters, Pipe Fitters, Plasterers and Roofers.

Stonemasons and bricklayers are at high risk of exposure to silica dust, welders to welding fume, road workers and plant operators to diesel fume, and carpenters and form workers are at highest risk of exposure to wood dusts.

Anyone working with wet cement or epoxy resins is at risk of contact dermatitis, and all outside trades have a higher risk of skin cancer due to exposure to the sun.

The trades covered by our Respiratory Health Hazards fact sheet series are:

• Asbestos Licensed Worker
• Bricklayer
• Carpenter
• Concrete Sprayer
• Demolition Operative
• Electrician
• Form Worker
• General Site Operative
• Glazier
• Painter/Decorator
• Pipe Fitter
• Plumbing/Heating Engineer
• Plasterer
• Road Worker
• Roofer
• Specialist Site Operative
• Steel Erector/Fabricator
• Stonemason
• Wall/Floor Tiler
• Welder

Hazard vs. risk – what’s the difference?

The terms ‘hazard’ and ‘risk’ are often used interchangeably, but in the context of occupational health, there is a difference.

A hazard is a chemical or physical or biological or psychological source of potential harm to a person or persons.  Some of these sources are a bigger hazard to health than others, in that their potential to cause severe ill-health is greater: some harmful substances may cause only temporary ill-effects, others lead to chronic, debilitating or fatal diseases.

A risk is the likelihood that a person may be harmed by that hazard. Not every risk to health is a high risk. Low level exposures to some substances may cause no ill-effect at all, while a high level can cause severe problems. Some substances are hazardous only if exposure to them happens over a long time and therefore the risk to workers exposed only periodically is low. Risks can also be made negligible or increased depending on the workplace environment, the work tasks involved, the methods of working, all things which can affect exposures.

What is occupational hygiene
(and what is its relevance to the construction industry)?

Occupational hygiene is about worker health protection.  It’s about preventing ill-health caused by the workplace. Or to put it more simply, it’s about:

• recognising the hazards,
• evaluating the risks,
• and then controlling exposures.

There are many situations across a construction site in which any or all of the various trades may be at risk of exposure to substances which are harmful to health. These hazardous substances need to be identified in the risk assessment at the start of the project, and a COSHH assessment for the use of these substances should be undertaken. [See HSE: A step by step guide to COSHH assessment: www.hse.gov.uk/pubns/priced/hsg97.pdf.]

A qualified Occupational Hygienist ( click here to link to the BOHS DIrectory ) can help with the complete COSHH assessment – which must identify problems, assess the level of risk and consider appropriate control measures – or elements of it.  Often, published Workplace Exposure Limits (WELs) and guidance surrounding known hazards can provide the information you need to assess the health risk.  Sometimes though, only specialist exposure monitoring techniques, like air or biological monitoring, can determine the level of risk for particular workers to particular diseases. An Occupational Hygienist can provide this specialist service. A qualified Occupational Hygienist can also advise on ventilation design, PPE/RPE specifications and supplier recommendations for all controls.

So, occupational hygiene is as relevant to construction as it is to any industry where workers face health hazards, and as the statistics show, the construction industry is full of health hazards to which the risk of exposure is high and controls are poor.

There are a multitude of construction trades, all facing a combination of different levels of different health risks, all of the time. It’s clear that not everybody on site everywhere understands this.  But Occupational Hygienists do. Link to fact sheet ‘Occupational Hygiene in context sheet’

What is a COSHH assessment?

Where, as is likely on a construction site, there are substances hazardous to health – such as chemicals, products containing chemicals, fumes, dusts, vapours, mists, nanomaterials, gases and biological agents (germs) – then the Control Of Substances Hazardous to Health Regulations 2002 (COSHH) require a COSHH assessment for the use of those substances. The COSHH assessment, and the strategy resulting from it for managing exposure to hazardous substances, can be made as part of, or as an extension of, the more general risk assessment requirements of the Management of Health and Safety at Work Regulations 1999 (MHSW).  COSHH does not cover lead, asbestos or radioactive substances because these have their own specific regulations, but the principles of health risk assessment and control for these substances are the same.

A COSHH assessment must identify problems, assess the level of risk and consider appropriate control measures for the use of the hazardous substances in the workplace. BOHS has produced a simple overview of how to carry out a COSHH assessment and there is HSE guidance, A step by step guide to COSHH assessment:

What is a Workplace Exposure Limit (WEL) and how do I find out if a substance has one?

Many thousands of substances are used at work but only about 500 of these substances have Workplace Exposure Limits (WELs), which must not be exceeded. WELs are British occupational exposure limits (as opposed to Indicative Occupational Exposure Limit Values (IOELVs) which are European exposure limits) and are set in order to help protect the health of workers. In most cases, the British limit (WEL) will be identical or very close to the European limit (IOELV).

WELs are concentrations of hazardous substances in the air, averaged over a specified period of time, referred to as a time-weighted average (TWA). Two time periods are used: long-term (8 hours); and short-term (15 minutes).

Exposures must be reduced where possible to below the WEL, to ‘as low as reasonably practicable’ (ALARP).

The relevant substances and their WELs are listed in HSE’s EH40/2005 Workplace exposure limits: www.hse.gov.uk/pubns/books/eh40.htm

There are many substances that are harmful to health that do not have a WEL. Identifying all the potential health hazards requires, as a minimum, reference to Regulations, safety data sheets, risk phrases, packaging labels, the HSE and manufacturers directly. It can be a complicated process, requiring specific experience or specialist technical knowledge and capabilities, where an Occupational Hygienist can help.

What are engineering controls?

Engineering controls range from small, on-tool extraction such as gun solder fume collectors, through dust hoods, fume cupboards, glove boxes and spray booths, to large-scale industrial installations.  They have in common the same occupational hygiene requirements:

• to collect or contain the dust, fume, smoke, mist, vapour, gas or other substance;
• to conduct it away from the worker reliably; and
• to keep exposures below relevant exposure limits.

An engineering control may be as simple as a mechanical fan for ventilation, but normally ventilation controls will have the following elements:

• a hood, enclosure or other inlet to collect and contain the contaminant as close as possible to its source;
• a simple indicator, such as a manometer or pressure gauge fitted near the inlet, to show the system is performing adequately;
• ducts, to remove the contaminant away from the source;
• a filter or other air-cleaning device normally located between the hood and the fan;
• a fan or other air mover, to provide air-flow; and
• more ducting to discharge cleaned air to a safe place outside, although sometimes, cleaned air can be returned to the workroom.

For anything other than the most basic of controls, specialist suppliers and/or engineering designers may be required to advise on/design/install controls. An Occupational Hygienist can help with the selection of reputable control system suppliers.

Note that respiratory protective equipment (RPE) – or any other type of personal protective equipment (PPE) – is not an engineering control.

Why can’t I just issue all site workers with PPE as a blanket protective method?

Risks should be reduced to the lowest reasonably practicable level by taking preventative control measures, in order of priority. This ‘hierarchy of control’ should be followed when planning to reduce risk from construction activities, rather than simply jumping to the easiest option to implement.

PPE – which includes safety helmets and hard hats, gloves, eye protection, protective and high-visibility clothing, safety footwear and safety harnesses, hearing protection and RPE – is often the simplest to implement. It is, however, lowest in the hierarchy, after elimination, substitution, engineering controls and administrative controls and should be the last resort, used only after all the other control measures have been considered and found ineffective or impractical.

Typically PPE does not provide adequate control on its own and can also be inconsistent in its protection because it relies heavily on worker compliance at all times (which, particularly on a large construction site, is difficult to supervise and monitor), correct fitting and usage, and it does not ‘fail safe’.