When Jason Johnstone was medically discharged from his job as an operator/trainer after being diagnosed with Hand Arm Vibration Syndrome (HAVS), he decided to explore ways to prevent it happening to other New Zealanders.

Jason is one of the very few people in New Zealand diagnosed with HAVS, a condition that can be permanently disabling, where nerves and blood vessels are damaged by exposure to repeated vibrations from hand and power tools.

Symptoms include tingling fingers, numbness, pain, weakness, loss of dexterity and impeded blood flow.

If caught early enough, HAVS can be reversible – but in Jason’s case, his symptoms persist, flaring up at the slightest change of temperature or during certain activities.

“All the crockery in our house has chips on it because when I do the dishes my fingers often go numb and I tend to drop the dishes. It’s much worse in winter and I’m pretty much stuffed when it comes to doing up buttons.”

But this hasn’t stopped Jason developing a new hand-arm vibration (HAV) monitoring device and launching a business to address what he calls a “massive grey area” in New Zealand around vibration exposure in the workplace.

Jason has worked with power tools for most of his life. His HAVS symptoms became more pronounced while he was working at the Tiwai Point aluminium smelter as an operator/trainer - a job that involved use of jack hammers amongst other tools. The smelter did have time limits on use of certain tools, but intensity was also a factor.

“My wife is a U.K. trained general surgical registrar and diagnosed me with HAVS, I had no idea what HAVS was at that time. I told the smelter doctor my hands feel funny and was sent to see occupational health specialist Professor David McBride who formally diagnosed me; Professor MacBride is a leading workplace disease expert in New Zealand.

“Basically, I was told l couldn’t use the tools anymore and was medically discharged from my job at Tiwai. But what I noticed was that no one had any idea how the injury had occurred. Sure, vibration emitted from tools and machinery had caused my injury but there was no data to explain this to the medical or health and safety professional. No one knew how much vibration I had been exposed to on a daily basis, nothing. It was all guesswork and seemed completely crazy, felt like I had wasted 20 years of my life”.

Jason’s experience has led him to research current figures on HAVS in New Zealand revealing what he sees as a major issue of underdiagnosis and misdiagnosis.

“According to ACC data on HAVS, there were only 40-50 cases of HAVS in New Zealand from 2000-2018,” says Jason. “This is unusual because 6230 cases were reported in the United Kingdom in half of that time. Even if we consider that the two workforces are similar, based on population statistics the incidence in New Zealand should have been 785 cases in 18 years or 44 cases per year.”

He also found that during 1 July 2009 and 30 June 2019, ACC data showed there were 5,342 cases of carpal tunnel syndrome compared to the United Kingdom’s 2,930. Furthermore, international research has shown vibration from hand tools does contribute to carpal tunnel injuries.

“In the UK, doctors are trained to recognise HAVS. In New Zealand they’re not. So, it’s very often misdiagnosed as carpal tunnel and that certainly has been my experience after being told I have carpal tunnel each time we relocate. I believe it’s a problem in New Zealand given workers’ exposure in our construction, forestry, manufacture, transport and agriculture sectors.”

Jason identified the need for a user-based device to monitor vibration and capture much needed data. He worked with a software developer Digital Stock in Invercargill to develop a HAV monitoring app and dashboard – and sought a real workplace in which to trial it.

“I was sitting at the traffic lights and saw a Delta Utility Services ute draw up beside me and noticed it had a load of tools in the back. So, I followed it all the way back to Delta’s head office, went in and asked to speak to the health and safety rep.”

Delta is a Dunedin-based infrastructure maintenance company that services electricity distribution and communications networks as well as maintaining the local authority’s green spaces. Delta had recently identified HAV as a workplace hazard for its employees who often use vibrating machinery such as mowers and weed eaters for long periods.

So when Matt Sadgrove, Delta Health and Safety Manager, came out to meet Jason, he was immediately on board to help him trial the device.

“I could see this was a smart idea, an innovative New Zealand-made tool to gather information to help us to make smarter decisions to keep our people safe.”

Matt is also a member of the New Zealand Community of Safety Innovation (COSI), a group of around 60 safety professionals who work together to identify new ways to improve health and safety. The group is supported by WorkSafe New Zealand, the New Zealand Institute of Safety Management, the Business Leaders’ Health and Safety Forum and the Health & Safety Association New Zealand (HASANZ).

“Our people are our biggest asset,” says Delta’s Matt. “Vibration is a major workplace health risk in New Zealand and Jason’s device is an opportunity to accurately identify, manage and prevent this risk across our workplaces.”

Over the next year, Delta’s health and safety team and crews trialled the device. The crew provided valuable feedback about the robustness of the device for use in the field. Delta also helped Jason refine the app he had developed to make the data easier to interpret once collected.

The trial resulted in Delta purchasing new robotic mowers for the business, eliminating the vibration hazard and removing the workers from other hazards such as wasps, working on slopes and sun exposure.

For Jason, the trial has resulted in working prototype vibration detection bands and launch of his business, Vibration Action. He is now seeking capital to support further development and commercialisation of the device.

“My ultimate goal is to incorporate the software into a Fitbit-like device that workers can wear all day, monitoring not just hand-arm vibrations, but sending and receiving real-time threshold alerts and capturing data. I have plans to develop other devices that measure whole-of-body vibration and workplace noise levels and incorporate them into one system that is fit for industry purpose”

Professor David McBride is Associate Professor in Occupational and Environmental Medicine at Otago University, David McBride, and says Jason’s device is just what New Zealand needs.

“As a workplace hazard, exposure to vibration is ubiquitous in New Zealand across construction, agriculture, horticulture and forestry. New Zealand needs to invest in more research in this area.

“With Jason’s device, we have for the first time a simple tool using available technology to scientifically assess risk in the workplace, helping raise awareness of the issue, support training and education and importantly ensure people take adequate breaks.”

Daniel Hummerdal, Head of Innovation at WorkSafe New Zealand which supports the COSI, says Jason’s device and Delta’s trial are a great example of the ingenuity and motivation in New Zealand to create better outcomes.

“This journey underscores the purpose of COSI to connect people and organisations that are developing and trialling their ideas in isolation and bring them together. We can all be inspired and learn from each other and not only spread good ideas quicker but help translate them into actions that create better outcomes.”

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