Ensure you have adequate lighting and ventilation.

Void spaces can become depleted of oxygen through over-occupation or displacement by another gas.

Confined spaces

USAR CAT 1 operators do not generally go into confined spaces.

Australian Standard 2865 identifies the procedures for safe entry into confined spaces. It is also a useful reference for anyone conducting void rescue operations. 

Confined spaces can hold the following risks:

* Explosion
* Fire
* Asphyxiation from gas, fumes, or lack of oxygen
* Drowning
* Secondary collapse

Flooding could occur both above and below the collapsed structure and could be the result of ground water, torrential rain or a ruptured water pipe.

Flooding can affect the equilibrium of the structure and contribute to secondary collapse.

Altered elevation – Ceilings and walls can become re-oriented when structures collapse, stacking together with the debris forming voids which make room identification very difficult. Interview locals to obtain information about:

* Colours of ceilings/floors
* Furniture types
* Hazards/chemicals, etc