New South Wales Fire Brigades have urged residents to take time out tomorrow to prepare an evacuation plan.

As August 31 has be designated Evacuation Day, firefighters have recommended that not only a plan be proposed but an actual evacuation also be carried out.

Bowral fire station officer Alan Barrell pointed out that in the past 18 months 13 people died in accidental house fires across the State because they didn't get out fast enough.

"As firefighters we know how important an evacuation plan is," Mr Barrell said.

"It's easy to become disorientated because of thick smoke. As well, the majority of fires happen at night.

"Planning for an evacuation only takes about 20 minutes, but it's 20 minutes that could save your family members' lives."

The station commander added that it was also a good opportunity to check smoke alarms and change batteries, and if necessary installing electrical safety switches and learning how to use fire extinguishers and fire blankets.