Will youth training or matches be cancelled because of haze?

That is the organiser's call. Many leagues use a 1-hour PM2.5 above 110 µg/m³ as the cut-off, and some check the 1-hour reading rather than the 24-hour PSI. Always wait for the organiser's final message.

Should I check the 1-hour PM2.5 or the 24-hour PSI?

Use the 1-hour PM2.5 to decide what to do in the next hour, and the 24-hour PSI to plan tomorrow. The PSI is a 24-hour rolling average, so it moves slowly.

Who counts as vulnerable in haze?

NEA's guidance singles out the elderly, pregnant women, children, and people with chronic lung disease or heart disease. They should avoid strenuous activity from Band 2 (above 55 µg/m³).

Sports training and matches in haze: how to use a PM2.5 cut-off

Decide with the 1-hour PM2.5 reading, not the 24-hour PSI. Many youth leagues call sessions off when the 1-hour reading is above 110 µg/m³; that is a league rule. NEA's guidance is to reduce strenuous outdoor activity at 56–150 and avoid it at 151–250.

Singapore now · as at 10:00 SGT

100 µg/m³ · Elevated (1-hour PM2.5, NEA official, worst region)

Within 15% of the cutoff (110). Could flip within the hour — check again before leaving.

Check your area →

What to do at each level

By 1-hour PM2.5 (µg/m³) band
Band	Healthy adults	Vulnerable people
Normal 0–55	Below the cutoff. Keep monitoring the 1-hour reading.	Below the cutoff. Keep monitoring the 1-hour reading.
Elevated 56–150	Within 15% of the cutoff (110). Could flip within the hour — check again before leaving.	Within 15% of the cutoff (110). Could flip within the hour — check again before leaving.
High 151–250	Above your cutoff (110). Expect cancellation; confirm with your organiser.	Above your cutoff (110). Expect cancellation; confirm with your organiser.
Very High ≥251	Above your cutoff (110). Expect cancellation; confirm with your organiser.	Above your cutoff (110). Expect cancellation; confirm with your organiser.

Basis: League cut-offs are set by each organiser (a common one is a 1-hour PM2.5 above 110). NEA's own guidance bands are 56–150 reduce, 151–250 avoid.

Why the 1-hour reading

The 24-hour PSI is a rolling average and can stay high for hours after the air has improved, or lag behind a sudden worsening. The 1-hour PM2.5 reflects the past hour, so it is what organisers use for same-day calls.

Choosing and using a cut-off

Pick the cut-off with your organiser and write it down. Re-check shortly before leaving, because the reading updates hourly and can cross the line within the hour if it is already close.

Haze Guide lets you set your own cut-off (default 110) and flags when the reading is within 15% of it.

Who decides, and what about vulnerable players

The organiser's decision is final. NEA advises vulnerable people to avoid strenuous activity for the next hour once the reading reaches Band 2 (above 55), even when a match is on.

If it is called off

Switch to an indoor session, shorten and lower the intensity, or use the 'cleanest window' on our 24-hour chart to reschedule.

Steps

Open the latest 1-hour PM2.5 for your region.
Compare it with your league's cut-off (for example 110 µg/m³).
If it is within 15% of the cut-off, check again just before leaving.
Follow the organiser's final decision.
Keep vulnerable players off strenuous activity once the reading is above 55.

Sources

NEA 1-hour PM2.5 readings (Singapore) — National Environment Agency (NEA), Singapore · official site · API / docs
data.gov.sg real-time API — Government Technology Agency of Singapore (GovTech) · official site · API / docs
haze.gov.sg regional haze situation and outlook — NEA, drawing on the ASEAN Specialised Meteorological Centre · official site

More guides

Running and cycling in haze · Children, school PE and recess in haze · Commuting and masks in haze · Windows, purifiers and indoor air during haze · Drying laundry outdoors in haze · Outdoor dining and events during haze · Pets in haze

General information, not medical advice. Follow your doctor and your school, league or organiser's final call. Data come from official sources; see data sources.