Technology could help make up for the imprecision of generalized rules. Last year, Garney Construction, a water and wastewater construction company based in Kansas City, Missouri, with offices around the country, partnered with Kenzen, a New York City-based tech startup, to pilot Kenzen’s wearable biometric sensor. The sensor, strapped around the upper arm, monitors indicators such as heart rate and core body temperature and alerts workers if they are showing signs of heat-related illness. The devices also send a warning to supervisors, though details are kept hidden to protect workers’ medical privacy.

Ryan Smith, eastern regional safety manager at Garney, said the sensors were tested last August and September on about 70 workers at 12 sites.
The sensors revealed some interesting data, Smith said. For example, workers at a Colorado site were overheating earlier in the day than expected, most likely because they were wearing more clothing in the cool mornings. The revelation prompted the employer to give workers a break specifically to remove the extra clothing. Heidi Lehmann, Kenzen’s co-founder and chief commercial officer, said the software platform that supports the sensors starts at about $40 per worker per month, with each sensor collecting tens of thousands of data points during an employee’s shift.
By the end of this year, up to 5,000 of the sensors are expected to be in use worldwide, Lehmann said. In the meantime, Kenzen is compiling a trove of data related to heat-illness risk factors, which could provide new insights for prevention.