A smoke alert has been issued for Mandurah by the Department of Parks and Wildlife following prescribed burns carried out to manage bushfire risk.
The smoke is particularly thick with DPaW recommending people shut their doors and windows and turn off air-conditioners.
Smoke may reduce visibility on some roads and motorists should take care, turn on headlights and travel at appropriate speeds when travelling in these areas.
People with conditions exacerbated by smoke should take precautions in line with their medical advice for these circumstances.
The smoke is expected to clear overnight.
More information on prescribed burns can be found at dpaw.wa.gov.au