Ever feel less productive when working at the office? Then maybe the problem lies in the air – literally.

Recent study commissioned by NUS team found that employee productivity dips by 1 percent when the PM2.5, a fine particulate matter less than 2.5 microns in size, in the air increases by 10 micrograms per cubic metre and stays at that level for 25 days. The finding was concluded after the NUS team spent more than a year gathering information from factories in China and scrutinising the output levels of two textile mills at Henan and Jiangsu.

The report was published in the American Economic Journal: Applied Economics on Thursday (Jan 3). According to NUS economist Alberto Salvo, the findings could be applicable to Singapore even on normal days when the country is not hit by haze, Today Online reports.

Productivity here could drop by 1 per cent if the PM2.5 increases from 15 micrograms per cubic metre to 25 micrograms per cubic metre if employees work in a “still atmosphere, with poor ventilation” over a fortnight or a month, said the associate professor. As a gauge, hourly PM2.5 levels in the central parts of Singapore on Thursday hovered between 14 micrograms per cubic metre and 25 micrograms per cubic metre.

Those who work in air-conditioned offices were not spared, added Assoc Prof Salvo, noting that his team studied Chinese workers who operated on factory floors that were air-conditioned in the summer when temperatures rise to and beyond what Singapore experiences.

While a 1 percent impact on productivity might seem inconsequential, Associate Professor Liu Haoming, who was part of the NUS team, said the effects were “subtle but highly significant”. This was because the results from the study demonstrated to factories that those with lax pollution controls, or have cut back on emission control equipment, were not helping their own bottom lines.

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Pollution levels were consistently high at the mills studied, with one of them recording a PM2.5 level averaging 85 micrograms per cubic metre — about seven times the safe limit set by the United States Environmental Protection Agency.

While pollution levels varied significantly from day to day, the NUS team found that the fluctuations did not immediately affect the productivity of workers. Rather, they established that a definite drop in output could be seen when examining more prolonged exposures of up to 30 days.

Assoc Prof Liu said their findings reflect a “psychological element” to the effects of air pollution. “High levels of particles are visible and might affect an individual’s well-being in a multitude of ways,” he added.

“Besides entering via the lungs and into the bloodstream… working in a highly polluted setting for long periods of time could affect your mood or disposition to work.”

Touted as a first-of-its-kind study examining prolonged exposure to air pollution, NUS said that there is “very limited” research on how living and working in such a polluted environment affects productivity, partly because worker output is difficult to quantify.

All the data collected as part of the study will be made accessible “to serve as a resource for other researchers to accelerate progress in this topic”.

Assoc Prof Salvo added, “We wanted to share all the information we gathered so that other researchers may use it well, hopefully adding to this literature’s long-run credibility.”

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