An AED should be checked at least once a month with a formal inspection, and visually glanced at more frequently, ideally every day it’s accessible. The American Heart Association recommends assigning specific people to perform monthly AED checks while encouraging anyone nearby to regularly look at the device’s status indicator light. Beyond these routine checks, a full program review should happen once a year.
Daily Visual Checks Take Seconds
The quickest and easiest layer of AED maintenance is a brief visual scan. Every AED has a status indicator, usually a small light on the outside of the case, that tells you whether the device is ready to use. A green light or checkmark typically means everything is fine. A blinking red light, a caution symbol, a wrench icon, or a chirping sound all signal a problem that needs immediate attention.
This isn’t a formal inspection. It’s more like glancing at a fire extinguisher as you walk past it. Anyone who works near an AED should know what the ready indicator looks like and what to report: a missing unit, visible damage to the case, or any warning light. Making this a habit among staff means problems get caught early, sometimes within hours rather than weeks.
Monthly Inspections Are the Core Requirement
A monthly check is the standard recommended by the American Heart Association and aligns with OSHA’s guidance that AEDs be inspected and maintained according to manufacturer specifications. This is the inspection that should be documented on a log sheet with the date, the inspector’s name, and the results.
During a monthly check, you should verify several things:
- Status indicator: Confirm the readiness light shows the device is functional.
- Physical condition: Look for cracks, dents, or any damage to the unit and its case or cabinet.
- Electrode pad expiration: Check that the pads haven’t expired and that the sealed packaging is intact.
- Battery status: Confirm the battery indicator shows adequate charge.
- Accessories: Make sure items like a razor, gloves, or a CPR barrier mask are still present if your kit includes them.
- Placement: Verify the AED is in its designated location and easily accessible.
If your AED’s manufacturer provides a specific checklist, use that one. If not, create your own based on the items above and keep it with the device or in a central file. Consistent documentation protects you legally and ensures nothing slips through the cracks when responsibility changes hands.
Your AED Also Tests Itself
Most modern AEDs run automatic self-tests on a regular schedule, typically once a day or once a week depending on the model and its settings. Some devices default to weekly, with options to configure the interval anywhere from daily to every seven days. Certain models also run a more thorough monthly self-test automatically.
These internal diagnostics check things you can’t evaluate just by looking at the device: whether the electrical circuitry can actually deliver a shock, whether the processor and software are functioning, whether the audio prompts work, and whether the electrode connection is intact. One FDA-reviewed device, for example, tests battery capacity, shock delivery circuits, ECG analysis electronics, CPR sensor function, and voice prompt audio during every automatic cycle.
Self-tests are helpful, but they don’t replace your monthly inspection. The device can’t tell you that someone moved it to a closet, that a mouse chewed through the pad packaging, or that the expiration date on the electrodes passed two months ago. Think of self-tests as a safety net, not a substitute.
When to Replace Pads and Batteries
Electrode pads and batteries are the two consumable parts of an AED, and both have expiration dates that need tracking. Most AED pads expire 24 to 30 months after purchase, though some models use pads rated for four or five years. Most AED batteries last four to five years.
Write these expiration dates on your inspection log and set calendar reminders well before they arrive. Running a monthly check and discovering expired pads is fine. Discovering them during a cardiac emergency is not. Some organizations keep a spare set of pads on hand so a replacement is always immediately available.
After any use on an actual patient, both the pads and the battery should be evaluated right away. Used pads must be replaced. The battery may still have life left, but you should check the remaining capacity before returning the device to service. This is also the time to check with the manufacturer about downloading any event data the device recorded.
Storage Conditions Affect How Often You Check
Where your AED lives matters. Devices stored in climate-controlled indoor spaces, like an office lobby or a school hallway, face fewer environmental stresses than those kept outdoors or in unheated buildings. AEDs come with manufacturer-specified temperature and humidity ranges for both operation and storage, and going outside those ranges can shorten the life of the battery, the pads, and the device itself.
If your AED is stored outdoors, in a parking garage, at a pool, or in any location with temperature swings, you may want to check it more frequently than once a month. A temperature-controlled outdoor AED cabinet can help keep the device within its recommended range. Even with a cabinet, outdoor units deserve closer attention because exposure to heat, cold, moisture, and dust accelerates wear on consumable parts.
Annual Program Review
Once a year, step back and review your entire AED program rather than just the individual devices. The AHA’s monitoring checklist includes a line for recording the date of your annual program review. This is the time to check with manufacturers for software updates, upgrades, or recalls. It’s also a good opportunity to confirm that the people assigned to monthly inspections are still in those roles, that training certifications for potential responders are current, and that your documentation is complete and organized.
An annual review catches the slow drift that monthly checks miss: a device that’s been in service for years and is approaching end-of-life, a building layout change that makes the AED harder to reach, or a new manufacturer recommendation you haven’t implemented yet. Keeping a written record of this review, along with your monthly logs, creates a clear paper trail showing your organization takes AED readiness seriously.