Wearable sensors can predict overheating, but are there privacy risks?

On a hot summer day in Oak Ridge, Tennessee, dozens of men removed pipes, asbestos and hazardous waste as they worked to decontaminate a nuclear facility and prepare it for demolition.

Clad head-to-toe in coveralls and equipped with breathing apparatus, crew members toiling in a building without electricity had no apparent respite from the heat. Instead, they wore armbands that recorded their heart rate, movements and level of exertion for signs of heat stress.

Stephanie Miller, a health and safety manager for a US government contractor doing cleanup work at Oak Ridge National Laboratory, watched a nearby computer screen. A color-coding system with little bubbles that showed each worker’s physiological data alerted her if anyone was in danger of overheating.

“Heat is one of the biggest risks we have in this work, even though we’re dealing with high radiation, hazardous chemicals and heavy metals,” Miller said.

As the world faces more record temperatures, employers are exploring wearable technology to keep workers safe. The new devices collect biometric data to estimate core body temperature — a high one is a symptom of heat exhaustion — and prompt workers to take cooling breaks.

The devices, which were originally developed for athletes, firefighters and military personnel, are being adopted at a time when the Atlantic Council estimates that heat-induced labor productivity losses could cost the U.S. about $100 billion annually.

But there are concerns about how medical information collected on employees will be protected. Some labor groups fear managers could use it to penalize people for taking needed breaks.

“Any time you put any device on a worker, they’re very concerned about tracking, privacy and how you’re going to use that against me,” said Travis Parsons, director of occupational safety and health at the Laborers’ Health and Safety Fund of America. North. “There are a lot of interesting things out there, but there are no guardrails around them.”

Vulnerable to heat

At the Tennessee cleanup site, workers wearing heat stress monitors manufactured by Atlanta-based SlateSafety are employed by United Cleanup Oak Ridge. The company is a contractor of the US Department of Energy, which has rules to prevent overheating in the workplace.

But most American workers lack protection from extreme heat because there are no federal regulations requiring them, and many vulnerable workers don’t speak up or seek medical attention. In July, the Biden administration proposed a rule to protect 36 million workers from heat-related illnesses.

From 1992 to 2022, 986 workers died from heat exposure in the US, according to the Environmental Protection Agency. Experts suspect the number is higher because a medical examiner might not list heat as the cause of death if a sweltering roofer suffers a fatal fall.

Establishing occupational safety standards can be difficult because individuals respond differently to heat. That’s where wearable device makers hope to step in.

How Wearable Heat Tech works

Employers observed workers for heat-related difficulties by checking their temperatures with thermometers, sometimes rectally. More recently, firefighters and military personnel have swallowed thermometer capsules.

“That wasn’t going to work in our work environment,” said Rob Somers, global director of environment, health and safety at consumer products company Perrigo.

Instead, more than 100 employees at the company’s infant formula plants were outfitted with SlateSafety armbands. The devices estimate the wearer’s core body temperature, and a reading of 101.3 degrees triggers an alert.

Another SlateSafety customer is a Cardinal Glass plant in Wisconsin, where four masons maintain a furnace that reaches 3000 degrees Fahrenheit.

“I’m right next to the face of the wall. So it’s them and fire,” said Jeff Bechel, the company’s safety manager.

Cardinal Glass paid $5,000 for five air monitoring arms, software and hardware. Bechel believes the investment will pay off; an employee’s two heat-related emergency room visits cost the company $15,000.

Another wearable, made by Massachusetts company Epicore Biosystems, analyzes sweat to determine when workers are at risk of dehydration and overheating.

“Until a few years ago, you used to wipe (sweat) off with a towel,” said CEO Rooz Ghaffari. “It seems like there’s all this packaged information that we’ve been missing.”

Research has shown that some devices successfully predict body temperature in controlled environments, but their accuracy remains unproven in dynamic workplaces, according to experts. A 2022 review of research said factors such as age, gender and ambient humidity make it difficult to reliably measure body temperature with technology.

United Cleanup Oak Ridge workers in protective gear may be sweating even before demolition begins. Managers see dozens of sensor alerts daily.

Worker Xavier Allison, 33, was removing heavy pieces of pipe during a recent heat wave when his rig vibrated. Since he was working with radioactive materials and asbestos, he couldn’t go outside to rest without going through a decontamination process, so he spent about 15 minutes in a nearby room that was just as hot.

“You sit by yourself and do your best to calm down,” Allison said.

The arm band notifies workers when they have cooled down enough to resume work.

“Since we implemented it, we’ve seen a significant decrease in the number of people needing medical assistance,” Miller said.

Collection of personal data

United Cleanup Oak Ridge uses sensor data and an annual medical exam to determine workloads, Miller said. After noticing patterns, the company sent some employees to see their personal doctors, who found heart problems the employees didn’t know about, she said.

At Perrigo, managers look at data to find people with multiple alerts and talk to them to see if there’s “a reason why they’re not able to work in the environment,” Somers said. Information is organized by ID numbers, not names, when it enters the company’s software system, he said.

Companies keeping years of medical records raise concerns about privacy and whether bosses can use the information to kick an employee out of a health plan or fire them, said Adam Schwartz, director of privacy litigation at Electronic Frontier Foundation.

“The machine could hurt, honestly, because you could raise your hand and say, ‘I need a break,’ and the boss could say, ‘No, your heart rate isn’t elevated, get back to work,'” he said Schwartz.

To minimize such risks, employers should allow workers to opt in or out of wearing monitoring devices, process only the data strictly necessary and delete the information within 24 hours, he said.

Wearing such devices can expose workers to unwanted marketing, said Ikusei Misaka, a professor at Tokyo’s Musashino University.

A partial solution

The National Institute for Occupational Safety and Health advises employers to institute a plan to help workers adjust to heat conditions and train them to recognize the signs of heat-related illness and provide first aid. Wearable devices can be part of efforts to reduce heat stress, but more work needs to be done to determine their accuracy, said Doug Trout, the agency’s medical officer.

Technology also needs to be paired with access to breaks, shade and cool water, as many workers, particularly in agriculture, fear reprisals for stopping to cool off or hydrate.

“If they don’t have water to drink and they don’t have time to do it, it doesn’t mean much,” said Juanita Constible, senior attorney at the Natural Resources Defense Council. “It’s just something extra to carry when they’re on the hot fields.”

Photo: A SlateSafety armband is worn by a furnace mason employee at Cardinal Glass in Menomonie, Wisconsin. (AP Photo/Abbie Parr)

Copyright 2024 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.