Enhanced heat stress at work system takes effect Friday

The Labour Department will introduce two new conditions for triggering the Heat Stress at Work Warning Signals. This comes after the public criticised the existing mechanism for being ineffective. The amended mechanism will take effect on Friday.

More than two weeks after Hong Kong's hottest day on record, the Labour Department announces an enhanced system for heat stress at work warnings to be used from Friday onward. The system will include two additional pillars.

That is, when the Hong Kong Observatory issues an extremely hot weather special alert, the amber heat stress warning will be issued, and the monitoring threshold for triggering the red signal will be lowered. Another new condition is that if more than 40% of the recorded temperatures at monitoring stations reach the mercury of 35 or above, the warning level will be stepped up by one automatically.

Labour Department's Commissioner, Sam Hui, says "The enhanced warning system will have a multi-pillar structure. We expect this new arrangement will continue to give timely warning alerts to workers working under heat stress caused by high humidity and poor air circulation, as well as triggering earlier and higher warnings to scenarios of abnormally high temperatures."

Asked why the department chose not to apply the Wet Bulb Globe Temperature, or WBGT, as an indicator of the system, which is suggested by meteorologists authorities say the Hong Kong Heat Index is more applicable to the city. But the department says they do not oppose the application of WBGT.

The Labour Department stresses that it has always adopted an open mind and will keep reviewing the heat stress at work warning mechanism.

Lam Chiu-ying, a former Observatory chief, says the WBGT is an international recognised standard to measure heat stress. He says Hong Kong is not a unique case and should not be treated differently.