Pilot study on welding fumes proves the potential of sensor measurements for a healthy workplace

Over one million employees in the Netherlands work with hazardous substances. Most notably, exposure to carcinogens and substances linked to COPD or asthma are major causes of premature death.

Figures from the National Institute for Public Health and the Environment (RIVM) show that in 2021, the estimated number of work-related deaths was almost 3,800. The majority of these deaths, nearly 3,000, were due to cancer and respiratory diseases. Alongside quartz dust, wood dust and asbestos, welding fumes are a major risk factor considered to be a clear cause of cancer and chronic lung diseases. Around 400,000 employees, particularly in the metal industry and shipbuilding, are exposed to welding fumes on a daily basis.

Hazardous substances as a silent killer

Reducing this health risk is a considerable challenge, Pim Berends knows from practice. As Improvement Coach and occupational hygienist at 5xbeter, Berends supports companies in the metalworking and electrical engineering industry with safe and healthy work practices. 'The biggest problem is ignorance among companies,' says Berends.

'Exposure to hazardous substances is a silent killer, the dangers of which are not immediately visible. Most people fall ill after they retire. Because employees do not immediately see the risks, work is not always done safely. Many welders have a positive pressure welding helmet, but it stays in the bag because they find a welding hood more comfortable. This means you are dependent on behaviour.'

Lack of understanding

The persistent nature of the problem is mainly due to a lack of awareness among employers and employees, in the opinion of Jody Schinkel, Business Developer at TNO. 'That is also largely due to current measurement methods.' 5xbeter currently commissions external parties to carry out periodic measurements at companies.

Berends explains: 'A traditional measurement involves drawing air through a filter with a pump. After at least 6 hours of measuring, sometimes a day, the filter is sent to a laboratory for analysis. You then receive a certificate with an overall result: the average exposure is so many milligrams of dust per cubic metre per day. That result provides zero insight into the exact sources, peaks or variations in time of exposure. But we actually really need to know the sources and peak exposures from welding fumes. Because welding fumes are dust, but dust can also be generated by grinding or sawing. And if you want to reduce exposure to welding fumes, what are you going to focus on?'

Breakthrough thanks to context sensors

Innovations in sensor technology are making it easier and easier to answer these questions. TNO has combined years of experience in air quality measurement and sensor technology into a modular sensor system. These sensors continuously measure exposure to dust, as well as variables from the environment such as noise, light and UV. This allows the context to be determined with a high level of precision: when did exposure occur, by which substance and from which source? A breakthrough.

Schinkel: 'To find out how we can use sensor measurements to better support companies with healthy working conditions, we proposed to carry out a pilot study on welding fumes together with 5xbeter.'

Linking smoke and light

The pilot study took place at metal manufacturing companies from the 5xbeter network. The study was conducted by TNO’s Sander Ruiter, Exposure & Risk Assessment Scientist: He explains: 'Measurements were performed using sensor boxes on the welder's chest and at fixed positions in the workplace. The multisensor we use for this purpose includes a dust sensor and a UV sensor. During welding, light and UV radiation are released, which are measured by the sensor. This allows us to see exactly when welding takes place and how much exposure is released in the process. Enabling us to distinguish between welding fumes and other substances.'

Following extensive instruction on the operation of the sensors by TNO on the first day, 5xbeter was able to supervise the measurements at the companies on the following pilot days itself.

A more cost-effective approach to measurement

For many companies, the high cost of often thousands of euros to perform a limited number of traditional measurements is currently a barrier to frequent measuring. In-house sensor measurements work out more cost-effective for employers: a sensor costs around €1,000, can be used on a regular basis and provides detailed insights for healthier workplaces.

Jody Schinkel explains there is still one hurdle to overcome: 'Companies need to identify risks based on accepted measurement methods. Our sensor is not quite there yet. We are still taking a closer look at what specific requirements the sensors need to meet to get them accepted as a standardised measurement method. However, the sensors can be deployed right now to detect sources and raise awareness.'

Impact on awareness and behaviour

In any event, the pilot study has convincingly demonstrated the practical advantages of this method of measurement. Jody Schinkel: 'Together with 5xbeter, we have successfully demonstrated the added value of sensor measurement in the workplace. What we did not do in the pilot is give feedback on the measurements with a view to exposure reduction.

This is an important part of TNO's Healthy Air Approach, which allows employers to reduce exposure to hazardous substances with targeted measures. What is the effect on exposure if an employee uses a welding torch with on-torch extraction? That provides all sorts of new insights.'

Pim Berends agrees with Schinkel. 'The sensor measurements can be a valuable addition to our Welding Smoke Improvement Check. Particularly if welding processes or materials are used that are currently missing from the check. What is very useful is the ability to provide employees with real-time feedback, influencing behaviour directly. That definitely helps to improve people's awareness and healthy behaviour.'