Occupational lung disease data released by the Health and Safety Executive (HSE) last year warned that 12,000 lung disease deaths occur each year that are estimated to be linked to past exposures at work, and 20,000 new cases of breathing or lung problems have been caused or made worse by work each year on average over the last three years.
“The key piece of legislation concerning the management of the risks associated with the day-to-day use of chemicals and other harmful substances in the workplace is the Control of Substances Hazardous to Health (COSHH) Regulations 2002,” explains Marie Warburton, respiratory interventions team at the HSE. “As well as traditional chemicals, COSHH applies to a wide range of substances including those generated during work activities, such as wood dust and stone dust.”
Josh Thomas, senior sales manager at Ashtead Technology, says that in order to evaluate workplace safety, monitoring data is usually compared with workplace exposure levels (WELs), which prescribes the maximum exposure level to a hazardous substance over a set period of time.
“Failure to comply with COSHH and WELs can result in financial penalties, prosecutions and civil claims,” he says. “Generally, WELs relate to particulate diameter because the health effects of particulates are heavily influenced by their size. Inhalable dust is that which enters the nose or mouth during breathing and is available for deposition in the respiratory tract. It includes particles with a width between 2.5 and 10 microns (PM2.5 – PM10), and the WEL for this fraction is 10 mg/m3 as an eight-hour time weighted average (TWA).
“Respirable dust is the fraction that penetrates deep into the gas exchange region of the lungs. It includes particles with a width between 1 and 2.5 microns (PM1– PM2.5), and the WEL for this fraction is 4 mg/m3 as an 8-hour TWA. Lower specific WELs exist for particulates that present a greater threat to health.” For example, silica dusts have a WEL of just 0.1 mg/m3 respirable dust as an eight-hour TWA.
When it comes to dust, both management and the workforce need to collaborate to address potential workplace health issues. For employers, Warburton says that the principles of COSHH are ‘risk assessment’ and proportionate ‘risk control’. The key points can be simplified as:
● Finding out what the health hazards are
● Deciding how to prevent harm to health by conducting a risk assessment
● Considering substitution
● Providing control measures to reduce harm to health and ensure they are used
● Keeping all control measures in good working order
● Providing information, instruction and training for employees.
Employees, meanwhile, should make sure that they understand what to do to prevent exposure:
● Ask if the material being used, or dust/vapour/fume from the work activity is hazardous
● Ask how the job should be done safely, without creating risks to health
● Follow all safe working procedures, including during cleaning operations
● Use controls such as dust extraction as they were trained to do
● If provided, wear respiratory protective equipment (RPE) properly.
When it comes to RPE, operators should also ensure that they are wearing the right type, such as respirators and breathing apparatus, for the job, are trained to use it, check and clean it before every use, ensure the filters or disposable parts are changed regularly, and that RPE is stored in a clean, dust-free place. A face-fit test for a mask may also be needed to ensure it fits properly. Employees should speak up if they find defects, or RPE doesn’t fit, is dirty or its filter is old, Warburton adds.
Safety equipment supplier Arco echoes these words. “The correct RPE, correctly used and correctly fitted, can prevent the vast majority of deaths,” it says. “The latest HSE statistics show that the number of reported lung disease cases has been on an upward trend since 2014. In fact, the number of occupational asthma cases seen by chest physicians in 2017 was similar to the reports 10 years ago. These statistics are concerning, and highlight the importance of ensuring workers fully understand how to use their RPE. Knowing how to use RPE is just as important as wearing it in the first place, so it’s vital employers place just as much emphasis on training as they do on procurement.”
Warburton adds that if the controls to protect workers from dust exposure include dust extraction (local exhaust ventilation or LEV) or other control equipment, the following questions should be asked:
● Were you involved in the design and selection of control equipment? The way you work may need to change to maximise the protection you get
● Have you been trained in how the control equipment works? You need to know how to use it effectively.
Your employer, the equipment supplier or other competent person should do this
● Can you tell if the control equipment is not working effectively? You should be trained to recognise the signs, for example, dust extraction equipment should have an airflow indicator to show that it is working properly
● Is the control equipment easy to use properly? If it forces you to work in an awkward way or prevents you doing the task properly, tell your employer and suggest improvements.
Campaigns and plans to improve and raise awareness of occupational lung health are also being recognised. The HSE has been running a #DustBuster campaign in the past six months, urging sites to show their support via social media site Twitter.
A Taskforce for Lung Health has also been set up to develop a five-year plan for improving lung health in England, whilst raising public awareness and understanding of lung health. Independent of government, it brings together representatives from 30 organisations who represent patients, health care professionals, the voluntary sector and professional associations such as the HSE.
The taskforce published a series of recommendations at the end of 2018 for what changes should be made in the next five years (www.is.gd/idamas). Dr Penny Woods, chair of the Taskforce for Lung Health, explains: “Many health care professionals, employers and employees don’t know enough about how environments and materials in the workplace can damage lung health, and new threats are emerging.
“As part of the prevention chapter in our five-year plan, the taskforce has made a series of recommendations to keep workers’ lungs healthy. These include improving the awareness of, and compliance with, COSHH to prevent and control workplace exposures.”
SELECTED PRODUCTS & SOLUTIONS
The scale of products and solutions for reducing dust exposure in industry is wide. As has already been established, PPE and RPE that meets certain requirements is useful. But dust extraction and control systems can also come in handy.
Dustcheck is a dust control company, supplying a range of cartridge, bag and panel filter products and systems to industry. Andy Darby, UK sales manager for Dustcheck, explains that in terms of industrial dust control, there are two main types of filter unit that Dustcheck provides – dust collectors and process filters. This is because dust problems in industry are usually caused by either a manufacturing process, where dust is being created by machining a raw product, or the product being handled is a powder itself.
Process filters let conveying air vent from the system, but prevent the dust from escaping into the atmosphere. Darby gives an example of filling a silo pneumatically with flour. “The air that is conveyed to the silo carries the product in suspension, once the product has been deposited the air has to escape from the vessel. This is where a process filter is applied so that the conveying air can escape but dust egress is prevented.”
These filters are also self-cleaning, which eradicates frequent filter changes, maintains consistent performance and discharges filtered product back into the vessel again so waste is eliminated. He adds: “There are different grades of filter media we can use in our units depending on the product being handled. We have many different options available and can even provide filtration efficiency to HEPA levels.”
Dustcheck dust collectors meanwhile, are standalone pieces of equipment that extract dust and collect it in centralised manner. By connecting to machinery and/or capture hoods with a ductwork system, it provides a way of having a single filter unit that can connect to multiple extract points then filter out and collect the dust safely in one place.
“The obvious benefit [of filter technology] is the cleanliness of the air for employees,” says Darby. “[Also], if there is a dusty atmosphere this can cause ingress to machinery and their components, causing failures and increasing maintenance costs.”
Dustcontrol UK provides mobile and stationary dust extraction systems. In October, it launched a new gas-powered extractor called the DC Storm LPG, which is said to last up to eight hours and doesn’t require cables, making it suitable for sites with limited electricity supply.
The machine’s 15 kW/21hp motor has the capacity to manage dust extraction in conjunction with work involving large-scale concrete construction and brickwork projects. The DC Storm LPG offers filter leakage of less than 0.005%.
Dustcontrol UK MD James Miller explains: “The DC Storm LPG is our most powerful mobile dust extraction machine to date. It’s perfect for large warehouse, civil and railway environments where electricity is not available or limited. What’s more, being run on propane makes it an environmentally friendly option, as opposed to fossil-derived electric.”
BOFA International is another designer, and manufacturer of fume and dust extraction systems. It has recently launched the PurePOD to remove harmful airborne dust generated in clinical working environments, notably during procedures such as reducing calluses, corns and filing and drilling nails.
These are just some examples of measures, procedures and equipment that can be implemented to reduce dust exposure to operators and sites. Every operation has a duty to protect its staff from life-threatening illnesses.