Singapore’s Ministry of Manpower (MOM) issued guidance Oct. 20 asking employers to adjust outdoor duties using hourly fine-particle readings, with the strongest precautions aimed at workers at greater risk from haze.
At an hourly PM2.5 concentration of 251 micrograms per cubic meter or higher, employers should prohibit outdoor work for elderly employees, pregnant employees and those with chronic heart or lung disease. The ministry advises cutting outdoor duties for other workers to a minimum. If those duties must continue, employers should provide masks or suitable respirators and arrange a break each hour, indoors where possible.
At readings of 151 to 250, MOM advises employers to avoid strenuous outdoor tasks for healthy employees and all outdoor work for vulnerable employees. If strenuous work cannot be avoided at that level, healthy workers should receive N95 or equivalent masks. From 56 to 150, employers should reduce strenuous outdoor work for healthy staff and avoid assigning it to vulnerable staff.
Employers should also consider rotating jobs, providing indoor breaks and using mechanical aids. MOM asked those with outdoor workers to keep at least a week’s supply of masks in their haze plans. The hourly bands are guidance; existing workplace safety law requires employers to assess haze risks and take appropriate measures. MOM gave no estimate of the cost of changing work arrangements or providing supplies.
Hourly PM2.5 readings measure fine-particle concentrations over the preceding hour and can change during a shift. The 24-hour Pollutant Standards Index (PSI) covers six pollutants and serves a different purpose: MOM says employers should use its forecast to plan the next day’s work. The National Environment Agency (NEA) has published hourly PM2.5 readings since 2014.
At 7 a.m. ET (7 p.m. Singapore time) on Oct. 20, NEA recorded hourly PM2.5 readings of 30 to 79 micrograms per cubic meter across Singapore. The 24-hour PSI ranged from 85 to 140, spanning moderate and unhealthy levels.
NEA reported smoke drifting from fires in Kalimantan toward Singapore and said prevailing winds could carry more smoke across the border. It forecast a PSI of 110 to 180, in the unhealthy range, for Oct. 21.
