There was no exception even after the Hong Kong Observatory in Tsim Sha Tsui recorded a maximum temperature of 36.9 degrees Celsius (98.4 degrees Fahrenheit) last Sunday afternoon, the highest since records began in 1884. The reason for only an amber warning is that the heat-stress-at-work reading took into account contributing factors that could moderate it, such as wind speed and humidity. Since the heat index measured at 10 stations was mostly in the amber range between 30 and 32, the department issued an amber warning. Given the extreme temperature, this is unconvincing to many people, and has prompted debate on whether the system is effective. Many people, whether indoor or outdoor workers, would empathise with the reaction of Chau Sze-kit, chairman of the Hong Kong Construction Industry Employees General Union, who said the amber alert seemed to have made a mockery of the record-breaking heat on Sunday.