Winstone Aggregates Adopts Adroit PMK to Support Dust Hazard Management and Worker Safety Training

Winstone Aggregates has 11 sites throughout New Zealand, from Whangārei to Gore, and Adroit PMKs are now being strategically deployed across these locations to monitor specific spaces such as mobile plant cabins, office blocks, MCC rooms, and laboratory spaces.

The business has a strong track record of investing in worker health and safety, with robust systems and practices in place that have consistently gone beyond minimum compliance. Over the years, Winstone Aggregates has implemented a wide range of initiatives to manage site risks, and the decision to adopt the PMK technology reflects that same proactive approach — using innovative tools to deepen insight, strengthen controls, and continue setting a high benchmark for health and safety performance on site.

Silica exposure remains a significant risk across multiple industries in New Zealand, with approximately 270,000 workers potentially exposed to respirable crystalline silica (RCS), and about 80,000 facing high exposure levels that meet or exceed the Workplace Exposure Standard.

Health and Safety Projects and Capability Manager, Charlene Donald explains that the PMK has become a key tool for illustrating the often invisible risks posed by dust exposure - complementing individual exposure monitoring programmes that measure a worker’s total dust exposure during their workday.

“The Adroit PMK tells us what’s happening in a specific area. It helps us understand what controls need to be put in place for those particular spaces. It’s a fantastic tool to be able to start those conversations and illustrate what is happening in the workplace,” says Donald.

An Invisible Hazard

Crystalline silica is a naturally occurring mineral found in materials such as rock, sand, and stone - all of which are common in quarrying and extractive industries. When these materials are cut, crushed, or disturbed, fine particles of respirable crystalline silica (RCS) are released into the air.

RCS particles are extremely small - less than 2.5 microns in diameter, around 100 times smaller than a grain of sand - and are invisible to the naked eye. Because of the serious health risks associated with inhaling RCS, including silicosis and other long-term respiratory illnesses, strict monitoring standards are in place.

In 2023, the Workplace Exposure Standard (WES) for respirable crystalline silica (RCS) was set at 0.025 milligrams per cubic metre (mg/m³) of air, averaged over an eight-hour working day, halving the previous 0.05 (mg/m³) industry standard.

Health and Safety Manager, Anya Hardy was the Winstone Aggregates team member who first identified the potential of the Adroit PMK and requested the purchase of the units says that the halving of the previous WES limit was the catalyst to look for new tools to measure and manage the problem.

“When the WES limit was changed, it just made things so much harder,” says Hardy. “Suddenly, you had to improve the accuracy of measurement or the method of detection, and the maximum level was lower as well. Where previously we couldn’t even measure the results as low as 0.025mg/m3, we were now at or close to those exposure levels,” she says.

The shift in regulation also revealed many unseen issues that were sometimes perplexing for the Health & Safety team. “I had a loader driver that, according to personal exposure monitoring, had higher than expected results,” Hardy says. “But if he's in a clean loader, the aircon is working, filters are cleaned, door and window seals are fine, then really, it should be a low result.”

Winstone Aggregates has been utilising Adroit technology for several years, with a fixed Adroit sensor installed at one of their sites since 2021 to monitor noise and dust levels. Recognising the advantages of real-time data collection, Hardy identified the opportunity to deploy a portable monitoring unit to better address dust issues as they occurred. She submitted a purchase request in 2022, initially acquiring a single PMK unit and subsequently expanded the programme by purchasing four additional units in 2023. The effectiveness of these portable devices became evident to her soon after their implementation.

“I can for example strap it into the loader and monitor it all day and see if it is, or it isn’t the loader that’s causing higher than normal results for the loader driver” she says.

“Or where two identical vehicles are reporting different dust levels - the PMK can help us identify whether one vehicle may have worn window seals that allow more dust into the cabin - which wasn’t possible without a portable monitor.”

Positive Behaviour Change

Beyond compliance, Winstone Aggregates is using the PMK proactively as a training and behaviour change tool. “The PMK gives us a visual way to show operators the impact of their actions - it’s one thing to tell people to shut a door, but when they see a spike in dust levels on a graph, it’s much more powerful,” Hardy says.

“Because they can’t see the silica dust that’s troublesome – they don’t believe in it,” Hardy explains. “But with these monitors I could clearly show them where the dust is, and they started believing: ‘Oh, actually we get this now – we can do something here.’”

One clear example stood out: “We had the PMK in one of the areas, and it was a dry day and dust readings were really high - then after two days of rain it was back under the limit. That just made them click - ‘Oh, actually, we can wet down the material and get our dust levels lower.’”

A key step in the process is to link monitoring results to task-based narratives, so in retrospect the team can see what task was happening at the time of a reading, and staff can see exactly how their actions affected the air quality.
Across the business, the response has been positive.

“Apart from my quarry managers, it's even got my health and safety advisors more excited about dust. They really love seeing the results and making the graphs - being able to show the data to people and explain why they need to wear their masks. It helped them make sense of it as well.”

And Hardy says she’s seen some real proactive actions taken as a result of that. “Now everyone’s got decent industrial vacuum cleaners,” says Hardy. “So instead of sweeping and stirring up the dust, we vacuum.”

The monitors also uncovered smaller, but critical behaviours. “People were coming in from outside and dusting themselves off in the control room – and boom, all the dust is back in the room. It’s not OK anymore to come into the Smoko Room with dusty boots. It’s about raising awareness that dust in general is not ok, it’s not “normal” to have dust, we can manage it properly.”

A New Tool for the Future

Charlene Donald says that the investment in the PMKs reflects Winstone Aggregates' deep organisational commitment to worker health and safety. “No job should be done unless we can do it safely,” she says.

“The PMK is particularly useful in high-risk environments where traditional controls are difficult to apply. In areas like crusher sheds where dust suppression with water is not feasible, the data helps justify the use of Powered Air Purifying Respirators (PAPR) or other specialised PPE. It’s about finding the most practical, pragmatic way of achieving safe outcomes,” says Donald.

Hardy says Winstone Aggregates’ experience is just the tip of the iceberg. “This is a national issue. It’s not just us – anyone working in the extraction industries has got the same challenge.” She’s already sharing their learnings about the PMKs with other businesses and she’s preparing to enter a case study on their work for an award at the upcoming quarry conference - it’s worked really well, and we want to show people what we’ve done,” Hardy says.

And Hardy says the Adroit PMK solution is remarkably cost-effective.

“To get people to come and do the testing for me all the time is really, really expensive and time consuming as well. Whereas with the PMKs I can try things - and if it didn't work today, I can make some changes and go and do it again tomorrow. And of course, it gives me live data so I can put the PMK anywhere in any quarry and I can sit in my office and have a look at it.

“So, honestly, I think they are great. This is the best toy that I've got,” Hardy says.