Welding Electrical Safety

Safety is a critical consideration for any welding project. Welding is a safe occupation when proper precautions are taken. But, if safety measures are ignored, welders face an array of hazards which can be potentially dangerous, including electric shock and electrocution. Weld Australia recently hosted a webinar on Welding Electrical Safety, during which experts shared insights on safety in the welding industry, and learnings from past catastrophes.

Weld Australia CEO, Geoff Crittenden, opened the online event, where he spoke about the importance of the Welding Safety Council (WSC), which has been in operation for two years. “The focus is to provide a pathway to a safer welding workplace, set clear expectations on what is required, and training,” Crittenden said.

The purpose of the WSC is to provide an exchange between industry leaders and legislative authorities to address issues in the sector, and work together to identify solutions for future practice. It is underpinned by the vision of eliminating loss of life or injury that may come as a result of welding.

Research into Welding Fatalities

David Hisey (Welding Health and Safety Advisor, Canadian Welding Bureau) joined the webinar from Canada. He shed light on welding safety, drawing on over 30 years of data and research. Hisey shared the details from 24 welding fatalities across Australia, New Zealand, Canada, China and the United States, and three injuries from an electrode shock-study.

The average age of the welders involved in the research study was 31.9, which Hisey believes is old enough to assume that they can be classified as experienced. “A welder who is 30 years old has probably been welding for a few years,” Hisey said.

The study discovered that 22 of the 24 deaths took place in a hot and wet environment, where the humidity was high, in comparison to the two deaths and one injury where conditions were cool and dry.

All 24 victims in the study had suffered from upper body electrode circuit contact, including eight who suffered electrode contact in the head, neck or face. It is important to note that the study did not measure whether it was raining outside and

the welder was under a shelter.

“The environment certainly appears to be a factor,” Hisey said. Clearly, humidity and rain increase the likelihood of injury or death when welding. “If you want to weld when it’s raining you have to be prepared to die and I don’t know if your boss wants that happening,” Hisey said.

Hisey also said 90 per cent of welders in a recent Canadian survey reported that electrode shock is a ‘normal part of the job’. This seems true in Australia as well, with close to one-third (32 per cent) of participants indicating that they had experienced an electric shock from a welding power source while on the job. “Prevention is only going to happen when you put education and regulation together,” Hisey said.

Carl Hussell, a Consultant at Quantec Safety Solutions, also joined the webinar to share his expertise. Hussell shared the findings from a 2011 Coronial Inquest after the death of Daniel Morris. Morris, who was 23 at the time, suffered from electrocution while working as a production supervisor for a labour hire company in Townsville. He was using a Liquidarc 245 welder, which was attached to a three phase lead and plugged into a switchboard. The Coroner found that Morris’ colleagues found him shaking after he was sitting on the metal hopper with his legs hanging down while he was welding.

Prevention is only going to happen when you put education and regulation together.

Inspectors from the Electrical Safety Office (ESO) concluded that the equipment had no faults. However, the conditions on the day of Morris’ death were humid. These humid and sweaty conditions greatly increased the conductivity of his skin, ultimately leading to his death when he came into contact with the electrode.

Sharing the findings of the investigation, Hussell reminded attendees about the importance of welding in a safe environment and understanding the dangers. “The welding was done in a shed and the sun was beaming through,” he said.

Environmental Standards

Welding under unsafe conditions— like extreme heat or wet weather —is a risk, which is underpinned by national safety and regulatory measures.

Standards Australia defines three welding environments:

• Category A: where the welder cannot contact the workpiece or a live part of the circuit, and the risk of an electric shock or electrocution by arc welding is low and normal work practices can continue

• Category B: where there is an increased risk of the welder contacting the workpiece or other parts of the circuit. This may take place where the surrounding temperature is less than 32°C or the welder is performing tasks in a cramped position

• Category C: where low body impedance of the welder, and a greater risk of the welder contacting the workpiece of the circuit leads to a significant risk of electric shock or electrocution.

Morris was welding in circumstances that brought the environment within a Category B or C at the time of his death. The Coroner’s Inquest also determined that Morris did not have the necessary training to perform ‘hot work’ activities like welding.

Health and Safety

Emeritus Professor John Norrish from the University of Wollongong specialises in materials welding and joining. According to Norrish, “The current that can flow through the heart is impeded by the clothing that the operator is wearing, skin contact and internal body impedance.”

Small increases in sweat and dampness reduce the impedance of the clothing and skin resistance exposing the welder to the risk of a severe electric shock, or worse.

Norrish also explained the differences between voltages. “At 25 volts, 95 per cent of the population would have a body impedance of around 6,000 Ohms. At 75 volts across the body, the impedance has dropped to around 3,500 Ohms.”

Bruce Cannon (Technical Publications Manager and Principal Welding Engineer, Weld Australia) also shared his thoughts on the importance of safety in the industry. “It’s crucial to note that if the welder fitted with a pacemaker feels unwell, cease welding immediately and seek medical assistance.”

Cannon also touched on additional safety requirements that are specific to welders with a pacemaker. “When I was taught to weld, I was taught to wrap the cable around me, don’t do that if you’ve got a pacemaker.”

Seven per cent of webinar attendees either had a pacemaker, or had worked with a colleague that had a pacemaker. Of those people, a further seven per cent reported that welding had interfered with the operation of the pacemaker.