Air quality in Singapore took a turn for the worse yesterday and reached "unhealthy" levels but this did little to deter the tens of thousands that descended upon the Marina Bay area to attend the Singapore Airlines Singapore Grand Prix and the post-race concerts.
While Sebastian Vettel thrilled the crowd with his victory last night, there was also plenty to celebrate for race promoter Singapore GP. This year's edition drew a three-day total of 268,000 fans - 5,000 more than last year - making it the second-highest attendance after the 300,000 at the inaugural race in 2008.
Among the first-timers at the Formula One race here was Australian Joe Grech, 51, who came with four family members. He said: "The haze isn't that bad. It looks more overcast than anything and didn't ruin our experience at all."
Retiree Doris Liang, 72, and her husband James Ng, 74, both had respiratory masks with them but were also unfazed. Ms Liang said: "The haze makes me cough a bit but it's not a problem. I'll just drink more water."
At 8pm yesterday, 10 minutes before the race began, the 24-hour Pollutant Standards Index (PSI) for all regions was over 100, with the south recording the highest figure at 123, and the north the lowest at 111.
In the south, where the Marina Bay Street Circuit is located, the one-hour PM2.5 concentration reading was in the "elevated" range of 78 at 8pm.
The one-hour PM2.5 concentration, which the National Environment Agency said is a better indicator of current air quality, measures the average hourly concentration of PM2.5 particles - the dominant pollutants in haze - and is meant to help people gauge whether they should go for immediate activities like a jog.
There are four bands on the PM2.5 concentration scale: zero to 55 for normal, 56 to 150 for elevated, 151 to 250 for high, and very high for above 250.
The 2014 and 2015 editions of the Singapore Grand Prix were held in hazy conditions but both proceeded without major incident.
Despite Singapore experiencing its worst air pollution in three years in the build-up to this year's marquee race, there was good news for F1 fans here. Singapore Airlines last Thursday announced it had extended the title sponsorship of the event for another two years to 2021.
SIA signed on as the Singapore race's title sponsor in 2014, and has since renewed the deal biennially.
SIA's deal for the first two years was believed to be worth between $10 million and $15 million annually, and was reported at $10 million a year for the next two years. The value of the 2018-2019 contract is not known.
The previous 11 editions of the night race have brought in more than $1.4 billion in tourism receipts.