The authorities announced yesterday morning that Seletar Airport was closed to all departing and arriving flights until 5am today due to “prolonged poor visibility caused by the haze”.

The Civil Aviation Authority of Singapore (CAAS) said the closure may be extended, “subject to visibility conditions”. Yesterday’s visibility fluctuated between 700m and 1,200m, below the airport minimum operating requirement of 1,500m.

“The airport, which operates under visual meteorological conditions, is therefore not able to accept aircraft arrivals and departures as pilots would not have a clear view of the runway,” the CAAS said. Two arrivals were diverted to other airports and eight departures were cancelled.

Separately, a CAAS spokesperson told Channel NewsAsia that Changi Airport’s air traffic controllers have taken the precaution of increasing the separation between flight take-offs and landings, as the airport’s Runway Visual Range (RVR) was below 1,500m. This has not led to any “significant delays” in flight departures and arrivals, she said.

She added that the RVR fell to a low of 800m during the prolonged period of haze in 1997, but Changi Airport remained open for flight operations.