Hong Kong's Labour Department is lowering the activation thresholds for its Heat Stress at Work Warning system, a move that will see alerts automatically upgraded when temperatures reach 35 degrees Celsius (95 Fahrenheit) across most of the city. The changes, announced on Thursday and effective from Friday, come after the three-tier system drew criticism for failing to issue higher-level warnings during a recent heat wave.
System changes
The Labour Department said the warning level will automatically be raised by one tier — from amber to red, or from red to black — when temperatures measured in many parts of Hong Kong generally reach 35 degrees Celsius or above. Commissioner for Labour Sam Hui Chark-shum introduced the new conditions on Thursday, according to the South China Morning Post.
Additionally, whenever the Hong Kong Observatory issues an "Extremely Hot Weather" Special Alert, the thresholds for triggering higher warnings will be lowered. Currently, the special alert automatically prompts an amber warning, the lowest level of the system.
Background of criticism
The adjustment follows public outcry over the recent heat wave, when only the amber alert was issued despite record-high temperatures. China Daily reported that no red or black warnings — which require employers to take measures such as increasing rest periods for workers based on physical workload and site conditions — have ever been implemented since the system's launch in 2023.
The system's failure to escalate was highlighted this month when temperatures in parts of Hong Kong exceeded 39 degrees Celsius, as noted by the South China Morning Post. The revamped system is intended to better protect outdoor workers during periods of abnormally high temperatures, the commissioner said.
The three-tier Heat Stress at Work Warning system, which advises outdoor workers to take precautions against heatstroke, has now been in place for three years. Under the new rules, officials hope the warnings will more accurately reflect the severity of heat conditions across the city.