Hong Kong to revamp heat stress warning system after record temperatures

Hong Kong authorities have pledged to review and improve the city's heat stress warning system for outdoor workers after record breaking temperatures triggered only the lowest level of alert. On Sunday, the Hong Kong Observatory reported a temperature of 36.9 degrees Celsius at its Tsim Sha Tsui headquarters, the highest temperature recorded since 1884. Despite this, the Labour Department's warning system remained at the amber level, which is the lowest of three possible alerts. Commissioner for Labour Sam Hui stated that his department will work with the Observatory to improve the system's sensitivity to unusually high temperatures, with a revamp expected by this summer.

The current system uses an index based on air temperature, humidity, wind speed, and solar radiation to issue amber, red, or black alerts. While red and black warnings recommend work suspensions for heavy physical workloads, they have never been activated. The recommendations provided by the system are not legally binding for employers. Undersecretary for Labour and Welfare Ho Kai-ming noted that the government is working with various departments to mitigate occupational safety risks.

Experts and officials have raised concerns about the current mechanism. Former Observatory chief Lam Chiu-ying described the system as baffling and decorative. Other experts have called for the adoption of international measurements that place greater weight on direct sunlight and an increase in the number of monitoring stations to ensure all districts are covered. Commissioner Hui noted that the current system is sensitive to hot and humid conditions but is less responsive to direct heat.