Dust

Dust can simply be described as particles in the air. The harm it can do to you depends on what the material is, don’t call into the misconception that all dust does the same thing.

Dust can be a problem in almost any industry. The hazards of dusts from silica and wood are especially common but there are many more substances that generate dusts which are hazardous to health. Construction workers have a high risk of developing diseases because many common construction tasks can create high dust levels.

Silica dust is a common hazard in construction work. Click here for more specific information on Silica hazards.

Health Effects of Dust:

Exposure to dust usually doesn’t lead to health problems until later in life. If you protect yourself now then you won’t suffer in future years, but if you do nothing, then by the time you feel the ill health effects it will be too late. Studies have linked dust in workplaces to asthma, bronchitis, lung, sinus and throat irritation, shortness of breath and skin problems. Frequent exposure over many years can be extremely serious. Infrequent exposure much less so.

Regularly breathing construction dust can cause diseases like lung cancer, asthma, Chronic Obstructive Pulmonary Disease (COPD) and silicosis. Construction workers have a high risk of developing these diseases because many common construction tasks can create high dust levels.

Recognizing Hazards of Dust in the Workplace:

There are three main types of construction dust: 

• Wood Dust: Created when working on softwood, hardwood and wood-based products like MDF and plywood

• Silica Dust: Created when working on silica containing materials like concrete, mortar and sandstone (also known as respirable crystalline silica or RCS); 

• Lower Toxicity Dusts – created when working on materials containing very little or no silica. The most common include gypsum (eg in plasterboard), limestone, marble and dolomite. 

Harmful construction dust is generated by many different work types. Some of the most common are:

• Cutting: eg wood, metal, concrete or paving stones; 

• Demolition work

• Grinding concrete or metal

• Sanding wood

• Sanding taped and covered plasterboard joints

• Dry sweeping

• Filling or emptying bags, especially cement 

• Handling or weighing loose powders such as cement powder

• Sieving sand or soil 

• Carrying or transporting materials in the back of a vehicle

• Stockpiling and moving large volumes of processed materials

• Crushing and grading

• Cleaning and maintenance work

Freshly cut trees contain large amounts of microbes, mainly moulds. The number of these increase if the logs are stored outside and under moist or humid conditions. The microbes can cause inflammation of the airways during debarking, sawing and transport.

Wood dust is combustible, and build-up around the workplace can increase the risk of fire or a dust explosion. 

Engineered wood products such as plywood, fibre boards, particle boards and laminated products contain formaldehyde, which can cause irritation of the respiratory system and eyes, a sore throat and runny nose. 

Dusts from second hand timbers may contain toxic paints, preservatives or lead.

Be aware:

Look around and ask yourself:

• Is the material you are about to use, naturally dusty?

• Is dust liable to be disturbed? 

• Is your work likely to create dust by mechanical or other means?

• Have any trees been freshly cut and debarked?

• Are you creating sparks or flames where there is dust build up?

• Are you cutting wood products such as plywood, fibre boards, particle boards and laminated products which may contain formaldehyde?

Again, be aware:

Is dust visible dust on pipes, surfaces, ledges, etc. This may indicate the presence of airborne dust. However, many dust particles are too fine to be visible under normal lighting conditions. A dust lamp, which provides a powerful beam of light, can be used as a quick method to show whether a fine dust is present, and helps to pinpoint the sources and movements of such dust. 

Assessing the Risks:

Consider the following:

• • Identify the hazardous substance or its potential development.

  • What is it’s source or how is it used?

  • In what quantities, where, how often and by whom?

  • What is the nature of the hazard? E.g. toxic or irritant

  • What is it’s possible route of entry into the body? E.g. eyes, skin, inhalation

  • Are current controls in place and how adequate are they?

  • If not adequate, what action needs to be taken?

  • Is the monitoring of the controls in place, by whom and what are the daily results?

  • Conclusion: Is the risk insignificant or significant with / without adequate control in place or is further risk assessment required?

Risk is high depending on one or more of the following:

• Task – the more energy the work involves, the bigger the risk. High-energy tools like cut-off saws, grinders and grit blasters produce a lot of dust in a very short time;

• Work area – the more enclosed a space, the more dust will build up. However, do not assume that dust levels will be low when working outside with high-energy tools;

• Time – the longer the work takes the more dust there will be; 

• Frequency – regularly doing the same work day after day increases the risks.

Action Plan if Dust Hazards are Believed to be Present:

   1. Elimination - remove the hazard completely from the workplace. E.g. source correctly sized raw materials, move from inside to outside and use lower powered tools.

   2. Substitution - replace a hazard with a less dangerous one. E.g. use machines that are fitted with effective local exhaust ventilation (LEV), use silica-free abrasives.

   3. Redesign - change the operation in some way to facilitate extraction of dust. E.g. implement adequate ventilation, wet the surfaces that are being cut and keep them wet.

   4. Isolation - isolate the operation away from most workers. Limit the number of people doing the work.

   5. Administration - putting rules, signage, or training in place to make a workplace safer. E.g. Induction training, supervision, highlighting hazards twice a day, rotate workers often, hand washing, clean work areas properly.

   6. Personal protective equipment (PPE) such as dust masks or respirators, is a less effective control and should not be used as a substitute for local exhaust ventilation. PPE is a last line of protection. In some circumstances it may be needed to supplement other measures, to reduce exposure to levels below the workplace exposure standard. People with skin sensitive to certain wood dusts should wear suitable protective clothing, eg. coveralls, long sleeves, and properly fitted industrial gloves. Check adequate, suitable, compatible, it fits and worn correctly.

Safety goggles are the only effective type of eye protection from nuisance dust because they create a protective seal around the eyes.

Never assume that any dust is safe. All uncontrolled dusts are potentially hazardous. In particular, any uncontrolled dry process or dusty work activity, especially in an enclosed environment, is likely to create a dust problem.

More Information Can Be Found At:

Operations Portal - Silica Hazards

Controlling wood dust hazards at work

Hire Association of Europe - Dangers of Dust

UK Health and Safety Executive - Construction Dust Info Sheet

UK Health and Safety Executive - Dust in the Workplace. Principles of Protection

Canadian Centre for Occupational Health & Safety - Health Effects of Wood Dust

Canadian Centre for Occupational Health & Safety - Effects of Dust on the Lungs