Official advice for New Zealanders living and travelling overseas

Nuclear incident

Nuclear incident

In many parts of the world, there is a risk that a nuclear incident could occur without warning. This could be due to an accident or natural disaster, or through an intentional act such as terrorism or warfare.

An incident at a nuclear power plant such as a major loss of reactor containment and cooling systems can produce a significant release of radioactive material into the environment which is carried downwind and settles on the ground and buildings in its path.

In addition to significant damage and casualties from blast and heat effects, a nuclear weapon detonation releases significant quantities of radioactive dust and debris into the air which takes more than 10 minutes to arrive back at ground level causing widespread contamination outside. This fallout gives off the most radiation during the first few hours following a nuclear explosion.

There are a number of steps you can take to help protect yourself and your family if you are nearby when a nuclear incident occurs.

Find shelter quickly and get inside

The best way to protect yourself - and your family – is to immediately get inside a building, shut all the windows and doors, turn off any ventilation and close any vents or fireplace dampers. Remove clothing and place it in a plastic bag outside out of the way as it may be contaminated.

Find something to cover your mouth and nose, such as a mask, scarf, handkerchief or cloth. Avoid touching your eyes, nose and mouth until you can wash with soap and water.

If the incident is a nuclear explosion, you will have at least 10 minutes to find shelter before fallout arrives. If possible, select a building that has brick or concrete walls and move toward the centre to put as much material between you and the outside. Underground parking garages and subway stations may also provide good shelter.

If you are in a vehicle and aren’t near a protective building, pull over and consider moving under an overpass or behind an embankment. Do not try to leave the area as there will likely be traffic jams and your car will not provide adequate protection from nuclear hazards.

Stay inside, decontaminate, follow instructions

It’s important you remain in the most protected location within your shelter for the first 24 hours after a nuclear incident unless there is an immediate threat (such as a fire, gas leak, or building collapse) or authorities have advised that it is safe for you to leave. This will significantly reduce your risk of exposure to radioactive material that is airborne or has deposited on outdoor surfaces.

If you think you may have been contaminated with radioactive material deposited from the plume you should have a shower, or if that is not possible then wipe or wash any exposed skin and hair. Pets that may have been contaminated can be taken to a separate room and then brushed and washed.

If you have a radio, tune in to any emergency broadcast and follow any instructions from authorities. Stay inside unless instructed otherwise. Do not attempt to self-evacuate until hazardous areas have been identified and safe evacuation routes have been established. If evacuating by car, keep the windows closed and the ventilation system turned off.

Note that any packaged food, drink or medicines inside your shelter or nearby shops and houses are still safe to consume or use.

Further information on safe decontamination can be found at:


Don’t take potassium iodide unless directed

Potassium iodide can have harmful health effects so it’s important you don’t self-medicate. You should only take potassium iodide if directed by a public health or emergency response official.

Potassium iodide can be used in a nuclear emergency to protect the thyroid from potential exposure to radioactive iodine. However, it must be taken immediately before or within 24 hours of exposure to be effective and is less effective for certain population groups. In addition, it does not protect other parts of the body against other types of radiation.

Preparing for a nuclear incident

There are a number of steps you can take to prepare for a nuclear incident. As a first step, identify potential shelters at or nearby your home, workplace, school and travel routes. Shelters are ideally located in a basement or in a building with brick or concrete walls. Vehicles do not provide adequate protection.

Once you have identified suitable shelter locations, you should then prepare and store:

  • survival kit or grab bag that includes dust masks, a torch, a battery-powered AM radio, and extra batteries or power banks
  • first aid kit that includes equipment and medications that can be used to treat injuries and burns, as well as a supply of any daily medications you may require
  • one-to-two weeks supply of bottled drinking water (2 litres per day per person) and water for washing/decontamination (2-4 litres per day per person)
  • one-to-two weeks supply of long-life food
  • spare clothes and footwear.

It is also recommended that you learn first aid skills suitable for treating trauma injuries and burns.


Further resources

Other pages in this section: