Outdoor industrial environments include industries such as construction and quarrying and are at high risk of excess hazardous dust exposure. This type of dust is referred to as construction dust. Construction dust is often a cause of serious ill health for many workers, causing diseases such as Chronic Obstructive Pulmonary Disease (COPD), Occupational Asthma and Silicosis. 

According to the UK’s Health and Safety Executive (HSE), the term construction dust “is a general term used to describe different dusts that you may find on a construction site” and is also produced through similar workplace processes. These different dusts include silica dust, created when working on materials such as concrete or stone, wood dust which is created when working on materials like softwood, hardwood, or wood-based products and ‘general dust’ created when working on materials like limestone or marble. 

The main issue relating to construction dust is often the failure to effectively eliminate or minimise workers’ exposure to it, in and surrounding any outdoor industrial environment, as well as the methods taken to do this. 

A broad range of workplace processes taking place in construction and quarrying essential to the job, like crushing, cutting, and grinding cause general dust to become airborne leading to exposure for workers. Similarly, when grinding into bricks, extraction of rock and similar processes using silica containing materials creates respirable crystalline silica (RCS) which, when inhaled, becomes incredibly harmful to the lungs.  

Often, the scale of the hazard depends on varying factors, including time, location, and methods of working. If people are working on tasks for longer, in a more enclosed space or are not using effective control methods for the dust, e.g. dry sweeping the dust, they are more likely to increase their risk of dust exposure.  

In many cases, it’s difficult to completely eliminate or substitute materials causing excess dust, due to the materials being used for the job. Therefore, workplaces may work in line with the Hierarchy of Controls to introduce engineering controls to isolate and limit workers from exposure to the hazard by altering the way the work. 

Construction dust is a major issue for multiple countries. Worldwide, there are over 200 million people employed in both construction and quarrying industries, meaning there’s a high risk of all outdoor industry workers being exposed to occupational lung diseases. For example, in the UK, it’s estimated that between 3,000 – 4,000 construction workers per year suffer from a work-related breathing or lung issues.  

Construction dust can affect different areas of an outdoor site. When completing processes such as grinding and cutting, dust may be closer to the breathing zone for individuals, heightening the chance of inhalation of hazardous particles. In contrast, processes like crushing and extraction may produce a larger amount of dust, making it airborne and spreading further affecting an entire site. 

Because these mentioned workplace processes take place outdoor, this finite dust can spread across entire sites and even further afield. The Environmental Protection Agency estimate that particle pollution generated in one area of a workplace can travel hundreds or thousands of miles. 

For all industry workers across an entire site, construction dust is a serious concern. Whilst workers directly involved in construction or quarrying processes are most at risk, any workers in nearby office cabins, the local communities or members of the public nearby can also be at risk, due to the nature of finite dust becoming airborne and spreading further afield.  

In 2019, Joanna McNeil was employed by an Australian quarrying and construction materials company, where her office was located in a portable cabin. Despite being located around 100 metres away from the quarry, Joanna developed silicosis due to exposure to hazardous silica dust at the age of just 36.

Almost anyone located on and nearby a construction or quarrying site can be severely affected by exposure to hazardous dust, whether directly involved in the workplace processes or simply by just being located nearby the worksite. 

Underground industrial environments include workplaces such as mining and tunnelling are at high risk of excess hazardous dust exposure. One of the most common health issues in underground environments is respiratory diseases, such as silicosis, black lung disease and lung cancer, caused by exposure to hazardous dust such as silica or coal dust. 

Silica dust is generated when rocks and sand are disturbed, which is very common in underground environments due to the nature of the heavy-duty processes. If inhaled, silica dust can cause silicosis, a serious long term lung disease which affects individuals breathing.  

Coal dust is generated during any common mining activity and exposure to coal dust can put workers at risk of black lung disease, also known as Coal Workers Pneumoconiosis. As coal mining is one of the most common forms of mining worldwide, the risk of black lung disease for all coal workers is high.   

Other types of dust which cause serious harm to health underground are generally referred to as ‘mine dust’. As with silica and coal dust, mine dust generated in underground applications can put those exposed at serious risk of lung diseases and respiratory problems. 

All types of lung diseases caused by dust in underground environments are linked to various occupational processes necessary to the job. In mining, common processes such as extraction and crushing causes natural minerals, rocks and stone to be disturbed causing dust such as silica to become airborne. In tunnelling, common processes such as drilling and blasting also disturb and break down sediments to create hazardous dust in the environment. 

As with most heavy-duty industries, dust is a by-product of the working processes, so the risks, management and control of the dust is predetermined. However, in underground environments, due to the lack of good air quality and limited atmosphere it is hard to fully control excess dust and ensure that risk management is followed to the highest level. Once dust becomes airborne, ventilation is limited, and dust becomes easily inhaled by anyone in the vicinity. 

Dust in underground applications tends to affect the immediate locations more than above ground, due to the nature of the confined space which the dust is generated in. The two most common underground industrial environments are mining and tunnelling, which are major sources of revenue for countries worldwide. 

According to various sources, there are over 2,300 active underground mines across the world, notably which are located in both North and South America and Australia. Most of these mines are used for the mining of hard-rock minerals, like gold, silver and iron, as well as soft-rock minerals, like coal. This highlights why exposure to silica and coal is so common during underground mining processes. 

Some of the largest underground tunnelling projects have taken place across the entirety of Europe as well as in South-East Asia in countries such as Japan and Malaysia. These projects were completed for new railroads, sewer systems and tunnels for driving, in order to improve and simplify life for local communities. Underground processes can occur anywhere worldwide, meaning that underground dust exposure underground is a threat for workers across the world. 

Most commonly, those who work underground are at highest risk of exposure to hazardous dust. As mentioned, due to the nature of the confined working space and limited atmosphere, hazardous dust can become increasingly easy to inhale for workers increasing the risk of lung diseases. 

In April 2024, the US’ Mine Safety and Health Administration (MSHA) introduce the new silica ruling which will aim to lower miners’ exposure to RCS and improve respiratory protection for all airborne hazards. The ruling firmly puts the emphasis on all miners’ health in underground industrial environments and focuses on improving the working environment to ensure that workers remain safe and healthy when working. 

The ruling also lowers the permissible exposure limit (PEL) for respirable crystalline silica to 50 µg/m3 for a full shift, calculated as an 8-hour time-weighted average (TWA) for all miners and establishes an action level for respirable crystalline silica at 25 µg/m3 for a full shift, calculated as an 8-hour TWA for all miners. The focus from MSHA is to protect all miners in the US from hazardous silica dust in underground applications. 

Elimination is the complete removal of the hazard in the workplace. For this it requires eliminating the risks completely at the source. This can be done by completely changing the process during work, completely removing the hazardous materials being used, or completely removing certain machinery in the workplace. 

Substitution is arguably a more suitable alternative than elimination. Although elimination is the preferred, substituting certain processes, materials, or machinery for safer alternative may be a more realistic option, such as choosing low dust alternative materials, or less powerful machinery which generates less gas. 

In scenarios where changing the entire workplace process isn’t possible, introducing engineering control to combat and control the hazard being generated is a suitable option. Controls such as Local Exhaust Ventilation (LEV), water suppression and damping methods, and enclosures and cabins ensures dust doesn’t become airborne.  

Administration controls ensures that workers remain away from direct contact with airborne dust in scenarios where dust cannot be eliminated, substituted or controlled. Examples like this include regular maintenance of all workplace environments, limiting worker exposure to gas generating processes and effective workplace clothing. 

Personal Protective Equipment is the last resort for controlling dust in the workplace, yet it can be effective if deployed correctly. With multiple options of PPE available, it’s important that PPE is correctly selected depending on the job which is being undertaken. Comfort, fit testing, individual usage and training are all essential for selecting the correct PPE.

• Respirable Crystalline Silica is one of the most hazardous types of dust workers can be exposed to. RCS forms many types of natural materials such as stone, sand and rock, and is generated when these materials are cut, ground or made fine through various different workplace processes. 

• Common industries exposed to RCS: Construction, mining + stone working 

• Asbestos dust is generated through the damaging of asbestos-containing materials such as cements, tiles and other products in manufacturing environments. When airborne, asbestos dust is easily inhaled due to its small size and scars deep into the lungs, causing lung diseases. 

• Common industries exposed to asbestos dust: Construction, demolition + manufacturing

• Substances and ingredients which are used to make pharmaceutical products can often create high levels of hazardous dust during processes such as milling, pressing, blending and grinding. API dusts can include organic compounds, metal powders and combustible properties. 

• Common industries exposed to API: Chemical Manufacturing + Pharmaceutical 

• Coal dust is generated in various underground environments when coal is being mined for, in rocks and other natural structures and materials. Cutting, grinding and blasting rocks makes coal dust easily inhalable, especially in environments with limited ventilation or space, such as underground. 

• Common industries exposed to coal dust: Mining, quarrying, gold (open-pit) mining + tunnelling 

• Construction dust can be generated from any kind of construction activity, whether cutting, drilling, mixing materials, building infrastructure, or other processes. Materials like stone, cement, sand and brick generate fine, respirable materials which create high levels of construction dust. 

• Common industries exposed to construction dust: Construction + quarrying 

• Grain dust is created when using barley, wheat and other natural materials from farming and harvesting. These processes in agriculture, as well as the manufacturing of grains in food production lead to grain dust exposure, generated from handling, transferring, milling and mixing grain. 

• Common industries exposed to grain dust: Agriculture + food production

• Flour dust is generated through mixing, cutting and handling flour, whether from initial farming and harvesting of crops, to processing it in food production. Exposure to flour dust can be dangerous, as its easily inhaled due to its small size and common use and worker exposure in food processing

• Common industries exposed to flour dust: Agriculture + food production 

• Textile dust is generated during apparel and clothing manufacturing due to processes such as drawing, carding, spinning, handling materials, and others, particularly due to the properties of wool, cotton and fibres. Occupational asthma and respiratory irritation is common for workers exposed to textile dust.  

• Common industries exposed to textile dust: Textile + apparel manufacturing 

• Fine metal particles generated through welding can lead to various occupational illnesses. Welding at high temperatures, above certain materials boiling point generates high levels of metal dust, particles and fumes which need to be effectively controlled during welding processes. 

• Common industries exposed to welding dust: Manufacturing + welding 

• Sawing, cutting and drilling into wood products often generates high levels of dust. This can be either hardwood dust, generated from oak or beech trees, or softwood dust, such as pine or fir trees. Exposure to hardwood dust can cause serious cancers, whilst softwood dust can cause respiratory irritation. 

• Common industries exposed to wood dust: Construction, forestry + woodwork 

By segregating processes which produce large volumes of dust, you can control the amount of dust your workers are exposed to. In some cases, it may even be possible to make the process entirely automated, meaning no workers are exposed to dust. Introducing a remote operation, e.g. a separate room or section within a facility meaning workers completing the dusty process never directly come into contact with the excess dust created. This process means that if workers have to complete a task which is likely to create excess hazardous dust, they spend as little, or if possible, no time exposed to the dust. 

In cases where segregation isn’t possible, extraction is an option to control excess dust. Local Exhaust Ventilation (LEV) systems can be built into machines or processes which create excess dust. LEV and extraction systems collect contaminants like dust and filter out the contaminants before they’re released into the air. This process can be used for multiple processes within the workplace such as storage bins, grinding mills, conveyors, mixing machines and many more, ensuring that when excess dust is created it does not come into direct contact with workers during these processes. 

Using less-toxic materials, where applicable, is another suitable method for controlling dust exposure in your workplace. For example, the use of pellets rather than powders, or replacing sand with garnet as abrasive blasting agent can allow workers to produce a similar end product during workplace processes whilst minimising risk of dust exposure. By substituting out materials for less toxic alternatives, workers can continue their processes throughout the day, at less, or almost no risk to their respiratory health.

The use of wet methods can provide almost no airborne dust during workplace methods. Damping down materials such as stone and concrete, which are used for many workplace processes and usually create high levels of dust when disturbed, can mean potential airborne dust is limited due to the particles binding together when wet. Similarly, methods of cleaning such as dry sweeping dust or compressed air lines can spread and disturb hazardous dust across the workplace, making it airborne and posing a threat to workers health, controlling excess dust and reduce the risk to workers. 

Excess dust is a consist problem in workplaces where highly dusty processes occur, especially if it is not possible to completely eliminate the risk of dust. By maintaining cleanliness, encouraging workers to work with care and instructing them how to control the dust produced in their work processes by following the methods mentioned, control of dust can become a regular process in the workplace.