Wildfire smoke, ash and what happens after a fire

Key rules

• Returning home: Go back only after the authorities lift the evacuation order, never earlier.
• Masks: Surgical and cloth masks do not stop fine smoke; staying indoors matters more than any mask.
• Ash: Never sweep ash or use a leaf blower; dampen it first.
• Burned slopes: Flood and erosion risk is highest in the first autumn storms and can last one to three years.

Smoke can harm you, even far from the fire

Stay indoors with windows and doors closed while smoke is present. Skip outdoor exercise. Smoke can travel hundreds of kilometres, so limit your exposure even if the fire is far away and the air quality is poor. Check the air-quality index of your region or of the national environment ministry.

Indoors, use air conditioning on recirculation, or an air purifier with a HEPA filter. Drink water. Don't smoke or burn candles inside.

Ordinary surgical or cloth masks do not stop fine smoke particles. A properly fitted FFP2 mask gives some protection if you must go out, but it does not replace staying indoors.

Children, older people, pregnant women and people with heart or lung disease, asthma or COPD are most at risk. Keep medication within reach. If you have trouble breathing, chest pain or a severe cough, call 112 or go to your health centre.

Going home after an evacuation

Go back only when the evacuation order is lifted. The announcement comes through the same channels as the order: 112, your town hall or the police. Expect road checkpoints, and don't try to return earlier.

When you are back:

• Check the structure, power, gas and water before using them. Call the utility or a technician if you are unsure.
• Watch for fallen trees, hot spots, smouldering embers and unstable ground.
• Throw away food that has been without refrigeration.
• Keep windows closed while smoke or ash remains.
• Report any flare-up to 112.

Photograph the damage for your insurer. Fire damage can also be covered by the Consorcio de Compensación de Seguros, which handles extraordinary risks. If your area is declared a disaster zone, ask your town hall about state or regional aid.

Cleaning up ash

Wear gloves, long sleeves, eye protection and an FFP2 mask. Never sweep, use a leaf blower or use compressed air, because they throw up fine dust. Lightly dampen the ash and pick it up with a damp cloth or mop, or use a vacuum with a HEPA filter.

Put the ash in sealed bags and throw it out with ordinary waste, following your council's rules. Don't wash large amounts down drains. Keep children and pets away, rinse play areas and furniture, and wash garden fruit and vegetables well before eating them.

For your car, rinse with plenty of water before wiping, because dry ash scratches. Replace the cabin air filter if it is clogged.

A burned building that may contain asbestos or other hazardous materials needs professional cleanup.

Burned slopes flood and erode

Fire strips away the plants and litter that catch rain and hold soil. Heat can also make the soil repel water. Rain then runs off instead of soaking in, which causes erosion, debris flows and flash floods. Ash and sediment can clog streams and reservoirs and pollute water.

The risk is highest in the first autumn storms after the fire, especially in Mediterranean areas with intense downpours. It usually stays high for one to three years, and longer on steep slopes. Be extra careful near burned slopes during storms, and avoid streambeds and low ground. Regional and national bodies often carry out emergency works such as mulching, log barriers and clearing channels.

Timeline and deadlines

• Wait for the evacuation order to be lifted, announced through 112, your town hall or the police: Before you go back

• Check the building structure, power, gas and water for damage before using them: As soon as you are back home

• Look out for fallen trees, hot spots, smouldering embers and unstable ground, and throw away food that went without refrigeration: On your first day back

• Keep windows closed while smoke or ash remains: For as long as smoke or ash persists

• Photograph the damage for your insurer: Before you clean up or repair

• Take extra care with burned slopes near you during storms: From the first autumn storms after the fire, for roughly one to three years

What to watch out for

• Smoke can harm you far from the fire: Fine smoke particles travel hundreds of kilometres and can hurt your lungs and heart. Children, older people, pregnant women and people with asthma, COPD or heart disease are most at risk. Stay indoors with windows and doors closed, avoid outdoor exercise and keep medication to hand.

• Masks and candles give a false sense of safety: Surgical and cloth masks do not stop fine smoke, and smoking or burning candles indoors adds to the pollution. Use a properly fitted FFP2 mask only if you must go outside, and run an air purifier with a HEPA filter or air conditioning in recirculation mode.

• Sweeping ash raises dangerous dust: Sweeping or using a leaf blower throws fine ash into the air, where you breathe it in. Ash from burned buildings may contain asbestos or other hazardous materials. Wear gloves, long sleeves, eye protection and an FFP2 mask. Dampen the ash and pick it up with a damp cloth, a mop or a HEPA vacuum, then bag it. Call professionals for burned buildings.

• Going back too early: Returning before the evacuation order is lifted puts you in danger from flare-ups, and you will meet road checkpoints. Wait for the announcement through 112, your town hall or the police. Once home, check power, gas and water before using them, and report any flare-up to 112.

• Burned slopes flood fast: Without vegetation, and with soil that repels water, rain runs off quickly and can cause erosion, debris flows and flash floods. The risk is highest in the first autumn storms and lasts roughly one to three years, longer on steep slopes. Avoid camping or parking in stream beds and below burned slopes during heavy rain, and follow local alerts.

Frequently asked questions

Does an ordinary mask protect me from wildfire smoke?

No, ordinary surgical or cloth masks do not filter the fine particles in wildfire smoke. A properly fitted FFP2 mask gives some protection if you must be outside, but staying indoors is still better.

Can I get smoke problems if the fire is far away?

Yes, smoke can travel hundreds of kilometres, so you can be affected even far from the fire when the air quality is poor. Check your regional or national air-quality index and limit time outdoors on bad days.

How can I clean ash off my car without scratching it?

Rinse the car with plenty of water before you wipe it, because dry ash is abrasive.

How long does flood risk last on a burned slope?

Flood and erosion risk stays raised for roughly one to three years, until vegetation recovers. It can last longer on steep slopes, and it is highest in the first autumn storms after the fire.

Who pays for fire damage to my home?

Start with your insurer, and take photos of the damage first. In Spain the Consorcio de Compensación de Seguros, a state insurance body, can also cover extraordinary risks, and in declared disaster zones you can check for state or regional aid.