During the coldest days of winter, a question that we often get from TSS clients is: “Do we need to do anything special to care for our Automated External Defibrillator (AED) when it’s freezing out?”

The last thing employers or individuals want – no matter the weather conditions – is for their AED to malfunction in an emergency situation. Protecting AEDs from extreme temperatures is certainly one way to ensure that your device works when you need it.

Cold weather can significantly affect the performance of an AED. From draining the battery to freezing the water-based gel found in the pads, the way an AED is stored in winter can impact its rescue-readiness.

How can you make sure that the AED is operating at the correct temperature?

Each AED manufacturer lists an operating temperature range and standby temperature range on the AED’s technical data sheet or operator’s manual. Operating temperature refers to the range in which the AED will perform in a rescue situation and is normally listed at 32° to 122°F (0° to 50°C) for most units. In order to maximize the life of AED pads and batteries, the AED unit should not be stored in temperatures that exceed the specified recommendations, which can vary by manufacturer.

Many public access defibrillators are stored outdoors in cabinets to make them accessible any time of day. If you choose to store your AED outside, make sure you get an appropriate cabinet for your device that will shelter it from cold or heat. While sub-zero temperatures can impact battery life and functionality of the electrodes, extreme heat can make batteries dangerous. Direct sunlight exposure in summer, for example, could raise temperatures in a glass-fronted storage cabinet above 149°F, the point at which batteries can leak, cause a fire or even an explosion.

We recommend indoor/outdoor cabinets for storing AEDs outside. For AEDs stored in vehicles, make sure to routinely check the unit for readiness. If the AED is chirping or displaying a service needed status indicator, take the unit indoors.

Contact us at for any questions you have about taking care of your AED this winter!