From Yik Jin Low
Cross-border haze led organizers to cancel nine half-marathons and marathons in Malaysia and Singapore scheduled between Sept. 6 and Nov. 1, according to a tally kept by the author’s website. Some were called off about two weeks out; others the night before, with runners already holding their bibs. It was a reminder that in Southeast Asia’s dry season, the air, not the course, can decide whether a race happens at all.
The races that didn’t happen
The cancellations started in Selangor. The PJ Half-Marathon on Sept. 6 was called off at the last minute by Petaling Jaya City Council on
health and safety grounds. The Star reported that, under the event’s terms, entry fees are generally non-refundable if a race is cancelled
because of unavoidable circumstances. On Sept. 20, the Tebrau City Half Marathon in Johor was cancelled and turned into a virtual run.
Three weeks after the PJ race came the biggest: the Kuching Marathon on Sept. 27 was called off at the last minute with more than 13,000 runners registered, some of them from outside Sarawak with flights and hotels booked. Abdul Karim Rahman Hamzah, Sarawak’s minister of youth, sports and entrepreneur development, said he had visited the race-pack collection venue earlier and had not been told of the cancellation.
October brought a cluster. In Malaysia, the Mersing Half-Marathon was cancelled and turned into a virtual run. HSN Putrajaya was called off,
with runners told they could still collect their medal and race kit. The Nilai 21K and Setiawangsa Half-Marathon were both cancelled for
unhealthy air quality, announced by the shopping malls that hosted them.
In Singapore, JomRun cancelled the Singapore Half-Marathon, and on Oct. 16 the Great Eastern Women’s Run, due Nov. 1, was called off over “worsening air quality.” A smaller corporate run, the Institute of Singapore Chartered Accountants race, was cancelled the night before it was due on Oct. 17, The Straits Times reported.
The author’s website, runsea.run, keeps a full list with each organizer’s stated reason and a source.
Not everyone cancelled
The decisions were not uniform. The Kuala Lumpur Standard Chartered Marathon went ahead on Oct. 4 but cancelled its Kids Dash races.
Organizers told adult runners, “You know your body best,” and urged anyone with underlying health conditions to weigh the decision
carefully, Malay Mail reported.
In Singapore, Garmin Run 2026 set out its plan in some detail.
Organizers said they would monitor the 24-hour pollutant standards index (PSI) and one-hour fine particulate (PM2.5) readings and make a go/no-go call at 11 p.m. on Oct. 24, the night before the Oct. 25 race, for about 6,000 registered runners. One option was to shorten the half-marathon to 10 km and move medical and aid resources onto the shorter route, the Straits Times reported.
Why the calls come so late
Haze moves with the wind, and readings can swing sharply within hours, so organizers have reason to wait for the latest data. Singapore
recorded unhealthy 24-hour PSI readings every day from Oct. 5 — as of Oct. 17, its longest stretch of poor air since the 2015 haze crisis, the Straits Times reported. Yet a late call shifts the cost to runners: the entry fee, sometimes non-refundable, and for anyone travelling, the
flights and hotels booked months earlier.
The guidance for athletes already exists. Dr. Ahmad Munawwar Helmi Salim, president of the Malaysian Association of Sports Medicine, told
The Star that, under National Sports Institute guidelines, athletes should cut training duration and intensity when the air pollutant index
(API) is between 101 and 200, and train indoors above 200. In September, four Para Sukma events in Selangor were postponed after the API reached 169 at noon.
What would help
Five changes would take much of the uncertainty out of the next haze season without asking organizers to run races in unsafe air:
The plan tied the race format to the one-hour PM2.5 band published by Singapore’s National Environment Agency: in Band 1, both races would run as planned; in Band 2, the half-marathon would move to the 10 km route; in Band 3 or 4, both races would be cancelled, Little Big Red Dot reported. On race day, Oct. 25, the event went ahead in an adjusted format with the 21 km race cancelled, Garmin announced on its Facebook page.
Publish the threshold before race week. Name the index (API in Malaysia, PSI or PM2.5 in Singapore), the reading and the time of the check.
Garmin Run did exactly this, tying its format to Singapore’s one-hour PM2.5 bands.
Set a decision timetable. A check 48 hours out, another 24 hours out, and a final call at a fixed hour would give travellers a chance to change plans before they leave.
State the refund, transfer and virtual-run policy at entry, not after the cancellation. Several organizers converted races to virtual runs
this season. Either approach can be fair if runners know beforehand.
Plan a shorter course. Cutting a half-marathon to 10 km, or a full marathon to a half, would keep an event alive on a marginal morning.
Use one channel. Runners pieced together news from event pages, mall Instagram accounts and newspapers. One official page, updated at set times, would help.
For runners, the lessons are practical: book refundable travel for dry-season races, watch the readings in the final week and keep
training. In Singapore, about 15 runners ran laps inside Marina Square mall on Oct. 17, covering up to 21 km indoors.
The races will come back. The question for the next dry season is whether runners will know, before they pay, what happens when the air
turns.
Alex Lowe operates runsea.run, a free guide to half-marathons and marathons across Southeast Asia that keeps a public record of races
called off in the region.
Yik Jin Low built runsea.run, a free guide to half and full marathons across Southeast Asia, which keeps a public record of every race called off in the region and why.
