Opinion | How to improve heat stress warnings for workers and avoid the confusion of flip-flops
- Why not reference global standards like the Wet Bulb Globe Temperature or other local heat stress research that specifically considers workers?
- To avoid inconsistencies, integrating the different heat warning systems is also a must
The three-tier Heat Stress at Work Warning system, introduced by the Labour Department on May 15, uses amber, red and black to indicate the severity of working conditions and is based on the Hong Kong Observatory’s heat index.
Professor Chan, who collaborated with the Observatory in the research and development of its heat index in 2014, found that a heat index of 29.5 was when Hong Kong’s excessive hospitalisation ratio started to increase, and that by 30.5, excessive hospitalisations increased to an alarming level.
Based on this, the Observatory improved its “very hot weather” warning system that same year to issue a special advisory when the heat index is forecast to reach 29.5, followed by a “very hot weather” warning when the temperature is forecast to reach 33 degrees Celsius or when the heat index reaches 30.5.
