Wildfire Smoke and Air Quality — Smoke AQI Guide

A fire breaks out hundreds of kilometres away. The sky looks hazy. Your throat tickles. Within hours, wildfire smoke air quality can push AQI from green to red — even in cities with no flames nearby. Smoke AQI is one of the fastest-moving pollution events you will encounter, and knowing how to respond can protect your lungs and your family.

This guide explains how wildfires affect air quality, what smoke AQI levels mean, and practical steps when fire season reaches your area.

Why wildfire smoke is so harmful

Burning vegetation releases enormous quantities of fine particles (PM2.5), carbon monoxide, and hundreds of other compounds. PM2.5 from smoke is especially dangerous because particles are small enough to bypass your nose and throat, lodge deep in the lungs, and enter the bloodstream.

Smoke travels farther than you think

Wind can carry wildfire plumes across countries and oceans. During major fire seasons, cities thousands of kilometres from the source have recorded hazardous air quality wildfire readings. You do not need to see flames to breathe the smoke.

How smoke AQI rises — and falls

Smoke AQI can change hour by hour depending on wind direction, fire intensity, and weather:

• Onshore or shifting winds can push a plume directly over your city, spiking PM2.5 within minutes.
• Stable, calm conditions trap smoke near the ground — visibility drops and readings stay high overnight.
• Rain and stronger wind often clean the air quickly, though ash and particles may linger on surfaces.

Check the hourly forecast on Aether during fire events. A reading of 180 at noon might drop to 90 by evening — or worsen if the wind shifts again.

Smoke AQI levels — what to do at each band

Moderate to Unhealthy for Sensitive Groups (51–150)

Light haze may be visible. Sensitive individuals should reduce outdoor time. Keep windows closed if you smell smoke indoors.

Unhealthy (151–200)

Everyone should limit outdoor activity. Children, elderly people, and those with asthma or heart conditions should stay indoors. Run air conditioning on recirculate if available.

Very Unhealthy to Hazardous (201–500+)

Treat this as an emergency for outdoor exposure. Stay inside. Seal gaps around windows and doors. Use a portable air cleaner with a HEPA filter in the room where you spend most time. Avoid vacuuming without HEPA filtration — it stirs particles back into the air.

Protecting yourself and your family

Indoors

• Close all windows and external doors.
• Run AC on recirculate — it filters some particles if filters are clean.
• Create a clean room: one closed bedroom with a HEPA air purifier running continuously.
• Avoid activities that add indoor pollution: smoking, frying without extraction, burning candles.

Outdoors and masks

Cloth and surgical masks do not block fine smoke particles. Use a well-fitted N95, KN95, or FFP2 respirator if you must be outside during elevated smoke AQI. Limit time to essential trips only.

Children and pets

Children breathe more air per body weight than adults. Cancel outdoor sport and keep play indoors during smoke events. Pets are affected too — shorten walks and watch for coughing or lethargy.

Recognising smoke vs other pollution

Smoke often brings a campfire or ash smell, reduced visibility, and a sharp PM2.5 spike without a matching rise in traffic-related pollutants. Dust storms raise PM10 more than PM2.5. Winter smog builds gradually over days. Wildfire smoke can jump AQI by 100 points in a single afternoon.

If AQI spikes suddenly and regional fire maps show active blazes upwind, assume smoke is the cause until conditions improve.

After the smoke clears

When smoke AQI returns to moderate or good levels, ventilate your home by opening windows for a cross-breeze. Replace HVAC filters if they ran during heavy smoke. Monitor symptoms — if cough or breathing difficulty persists, see a doctor.

Fire season is lengthening in many regions. Building a habit of checking wildfire smoke air quality before outdoor plans is one of the simplest ways to stay ahead of the next plume.

Monitor smoke AQI live on Aether

Aether tracks live AQI and PM2.5 with hourly forecasts so you can see when wildfire smoke reaches your city and when air quality recovers. Check before school runs, commutes, and outdoor work — and share readings with family and neighbours during fire season.