Replacing AED pads is straightforward and takes under a minute on most devices. The exact steps vary slightly by brand, but the process follows the same general pattern: open the device, remove the old pad cartridge or connector, insert the new pads, and confirm the status indicator shows green. Keeping fresh pads installed is one of the most important parts of AED maintenance, since expired or degraded pads can fail to deliver a shock properly.
Step-by-Step Pad Replacement
Most AEDs use either a cartridge system or a plug-in connector. Cartridge-style devices like the Philips HeartStart have a latch at the top edge of the unit. Slide the latch to the side, and the pads cartridge releases. Lift it out, then take a new cartridge from its sealed package and press it into the cartridge well until it clicks into place.
For AEDs that use a plug-in cable instead of a cartridge, the process is similar. Open the lid, disconnect the old pad cable from its port, and plug in the new one. Some models come with pads that are pre-connected to the device during storage, so you only need to swap the entire pad assembly rather than deal with a separate cable and connector. Either way, after installing the new pads, close the lid and check the status indicator. A green “ready” symbol means the device recognizes the pads and is operational. If you see a red warning symbol, the connector may not be fully seated. Reopen the device and press the cartridge or cable in more firmly.
How to Tell Your Pads Need Replacing
Every AED pad package is printed with an expiration date. Most pads last about two years from the date of manufacture, though the exact shelf life depends on the brand and model. Beyond checking the date manually, your AED itself will alert you. Devices use beeps, chirps, or periodic alarms paired with a warning light or screen message to flag problems. Pads can trigger these alerts when they are expired, approaching expiration, damaged, or not the correct type for that AED.
A loose or partially unplugged connector will also cause beeping, because the device cannot confirm it is ready. If your AED starts chirping and you are not sure why, check the display or message window first. Many units will spell out the specific issue: battery, pads, temperature, or a general service request.
Why Expired Pads Are a Problem
AED pads rely on a layer of conductive gel to transmit electrical energy through the skin and into the heart. Over time, that gel dries out inside the sealed package. When it does, the electrical resistance between the pad and the patient’s chest increases significantly. Higher resistance means less of the shock’s energy reaches the heart, and in a worst case, the AED may display a false “no signal” or misread the heart rhythm entirely. Research on gel-based electrode systems has shown that degraded gel can cause the device to display what looks like a flatline even when a rhythm is present, especially as more shocks are delivered through the same pads.
Temperature and humidity accelerate this degradation. Storing pads in environments that are too hot, too cold, or excessively humid breaks down both the adhesive and the conductive materials. Poor adhesive means the pads may not stick firmly to the patient’s skin, creating air gaps that further reduce shock effectiveness. Store your AED in a climate-controlled area, out of direct sunlight, and within the temperature range listed on the packaging or in the device manual.
Adult Pads vs. Pediatric Pads
AEDs are programmed to deliver adult-dose shocks of 150 to 360 joules when standard adult pads are connected. For children under eight years old, that dose is dangerously high relative to body weight. An initial shock of 150 to 200 joules translates to roughly 6 to 8 joules per kilogram for an average eight-year-old, and escalating doses on subsequent shocks can push that to 15 joules per kilogram.
Pediatric pad systems solve this by raising the electrical resistance in the pad and cable, diverting some of the current away from the patient so the delivered energy drops to about 50 to 75 joules. If your AED is located somewhere children may need it, such as a school, daycare, or community pool, keep a set of pediatric pads on hand and replace them on the same schedule as your adult pads. The replacement process is identical. When installing new pads, just make sure you are inserting the correct type for the situation. Most pediatric pad packages are clearly labeled and use distinct colors or markings.
Setting a Replacement Schedule
The simplest approach is to write the expiration date on a calendar or set a recurring reminder for a month before the pads expire. Many organizations that manage AEDs in public buildings assign someone to do a quick monthly visual check: open the case, confirm the status indicator is green, glance at the expiration date on the pads and battery, and close it back up. This takes less than 30 seconds and catches problems before they matter.
Some AED program management services will send you replacement pads automatically before yours expire. If you purchased your device through a distributor, ask whether they offer a subscription or reminder program. Keeping a spare set of pads in the same cabinet as the AED is also a practical backup, as long as you rotate stock and check expiration dates on the spares too.
Disposing of Old Pads
Expired electrode pads that have never been used on a patient are not considered hazardous waste. You can place them in the regular trash or drop them at a recycling center. This is different from expired AED units and battery packs, which are classified as hazardous waste and require disposal at a hazardous waste recycling facility. Pads that have been used on a patient during a cardiac emergency should be treated as medical waste and disposed of according to your local regulations, which typically means using a biohazard bag and coordinating with a licensed medical waste service.