Extraction systems for welder protection: a handy overview

5000 cases of cancer are linked to the workplace in Australia each year. The most common causes include dusts, chemicals and gases that are released, particularly during welding work. To protect employees, Safe Work Australia (SWA) has a workplace health and safety strategy. In this context, it has developed a code of conduct with possible occupational safety measures for companies. One of the most important of these measures is the integration of an extraction system that reliably detects hazardous substances. But the issue is often associated with major challenges for companies. From source extraction through extraction hoods to general ventilation, the range is so large that it can be difficult to keep track of it all. Here’s a handy overview to help.

A safe workplace is important for new employees — occupational safety and ergonomics are becoming increasingly significant. Especially when welding, many hazardous situations occur in everyday working life. Electric shocks, explosions, blinding of the eyes — to name but a few. Particularly perilous for companies and employees are toxic fumes, gases and vapours that are produced during welding processes. Potential consequences are lung damage or, in the worst case, cancer. In Australia alone, about 3.6 million people are exposed to carcinogenic substances at work and their lungs also suffer from hazardous dusts. Lung diseases occur through repeated exposure and, in extreme cases, even through one-time contact with hazardous substances. Proper handling of the substances is essential for companies and employees.

SWA strategy for health and safety

The most common occupational diseases include asthma, asbestosis and pneumoconiosis. To avoid health consequences and ensure safe workplaces, companies need to take some precautions. SWA sets national guidelines, with the Australian Government establishing the body in 2008. On 31 October 2012, SWA launched the ‘Australian workplace health and safety strategy 2012–2022’. It is based on two fundamental principles:

1. All workers, regardless of their profession or occupation, have the right to a healthy and safe work environment.
2. Well-designed, healthy and safe work will enable workers in Australia to lead more productive working lives.

The main focus of the strategy is on occupational lung disease. That’s why SWA has developed a work plan that is currently being implemented. Its aim: to create awareness of the obligations to remove harmful substances. In 2016, SWA published a code of conduct on welding. The code of conduct provides guidance for companies to manage the health and safety risks associated with welding. It applies to all workplaces covered by the Work Health & Safety (WHS) Act where welding operations are carried out.

Legal basis and responsibilities

The occupational exposure limit for welding fumes is clearly defined by law. It is currently 5 milligrams per cubic metre. The duty of care and verification of the value lie with the company, but the company does not bear the responsibility alone. Every person involved in the work process contributes to a safe working environment. For example, designers, manufacturers and suppliers of technical equipment and materials must ensure that the materials do not pose risks to health and safety. This duty includes the performance of tests and analyses as well as providing specific information.

Workers have a duty to take reasonable care of their own health and safety and must not compromise the health and safety of others. They have a duty to follow all reasonable instructions and to carry out their work in accordance with all relevant workplace policies and procedures. If personal protective equipment is provided by management, the worker must use it in accordance with the information, instructions and training.

The STOP principle sets out the hierarchy of protective measures.

The STOP principle simply explained Substitution → Users must check whether the use of low-emission processes is also possible. Technical measures → Sufficient protection must be provided by technically effective protective measures. Organisational measures → Users must ensure that sufficient protection is also guaranteed by organisational measures. Personal protective equipment → If sufficient protection is not ensured with the help of the measures already taken, individually effective measures, such as respirators, are necessary.

The development of technical measures is now well advanced. There is a wide range of different extraction systems available, for example. Choosing the right equipment is a major challenge for many companies. Which system reliably protects employees from hazardous substances? Is the system suitable for the company? Does it meet all the necessary requirements? From source extraction through extraction hoods to general ventilation, the range is so large that it can be difficult to keep track of it all.

Overview: Extraction systems at a glance

1. Source extraction integrated into the welding torch

If possible, the welding fumes should be captured directly at the point of origin. The closer the extraction is to the point of origin, the more efficient the capture of the hazardous substances. Modern systems offer numerous useful additional functions that make welding work significantly safer and more comfortable. During torch-integrated extraction, the welding fumes are captured directly at the point of origin.

2. Source extraction with extraction arm

A popular alternative to the torch-integrated variant is extraction with extraction arms. Low-vacuum source extraction is particularly convincing because of its flexibility. In the ideal case, the extraction arms can be freely positioned and are self-supporting, so they remain where the welder has positioned them during tracking. An extraction hood at the end of the arm reliably captures the hazardous substances. With extraction arms in lengths from 1.5 to 10 metres, they also handle larger areas without any problem. Detection is still possible with a distance to the emission source of 300 to 400 millimetres.

Checklist An extraction hood should fulfil these criteria: 360° swivelling: easy tracking increases the likelihood that the breathing zone never enters the smoke cone. A flange-shaped cover on the sides prevents sucking in false air, preventing it from reaching the air cone. The hood achieves a 40% higher extraction rate than purely oval hoods. Integrated light for better visibility of the workplace.

3. General ventilation

Technical general ventilation may be required as an additional ventilation measure. In this way, companies ensure that the limit values for employees at the surrounding workplaces are also complied with. These employees do not carry out any welding work themselves but can be exposed to certain concentrations of welding fumes and gases in the production environment. Extraction is mostly carried out at a height of three metres or more. A distinction is made in general ventilation between mixed and layered ventilation. Layered ventilation draws in the rising polluted air in order to return it filtered to ground level. With mixed ventilation, air is supplied to the hall via grilles on the ceiling. The general ventilation air is then mixed.

4. Personal protection measures

According to the STOP principle, personal protective measures are necessary if welding fume extraction is not sufficiently possible for technical reasons. In that case, the employer is obliged to provide their employees with suitable equipment. For protection, use of the following respirators is recommended:

• Ventilated helmets or hoods
• Masks with blower and particle filter
• Full face masks or mouthpiece sets
• Self-contained respirator devices (eg, ventilated helmets/hoods with external air supply)

In order to integrate the right extraction system, companies must familiarise themselves with the many possibilities. Various factors and circumstances of the company are decisive and influence the choice of extraction system. A combination of different systems is also possible in order to protect the health of employees in the best possible way and to create an attractive, safe workplace.

Occupational safety as a process: campaign for healthy lungs

The preceding descriptions prove one thing above all else: there has been significant progress in occupational safety in the past few years. Today’s welding workplaces are safer than ever before, not least thanks to efficient and powerful technology. Another reason for this is SWA’s ongoing efforts to promote safe workplaces and worker health. Since its founding year in 2008, the organisation has achieved a lot with codes, guidelines and awareness campaigns, creating a growing awareness of the issue — both among employees and companies. But occupational safety and health is a process that is constantly evolving and is far from complete. At the same time, it is a complex issue that requires continuous education and guidance in companies. The organisation is working on this through various national campaigns under the slogan ‘Clean Air. Clear Lungs’. SWA, in cooperation with the Lung Foundation Australia, is calling on companies to educate themselves further about the topic. The motto: create even safer jobs in the future through information and education.

Image credit: Kemper GmbH