The Short Answer

False.

Most public access defibrillators are highly reliable and spend much of their life continuously monitoring their own condition through automatic self-tests.

Modern AEDs are designed to sit ready for years and then perform when needed. While faults can occasionally occur, a properly maintained defibrillator is an extremely reliable piece of lifesaving equipment.

Why Do People Believe This Myth?

It's understandable.

Many people see a defibrillator sitting in a cabinet for years and wonder:

"How do we know it still works?"

Others may have heard stories about flat batteries, expired pads, or damaged equipment and assume that public defibrillators are often unreliable.

The reality is rather different.

Most AEDs spend their entire lives checking themselves.

What Self-Checks Does an AED Perform?

Modern defibrillators regularly test their own systems.

Depending on the manufacturer, these self-tests may occur daily, weekly, monthly, or every time the device is switched on.

The AED checks things such as:

• Battery condition

• Internal circuitry

• Software integrity

• Shock delivery capability

• Electrode connectivity

If a problem is detected, the AED will normally display a warning indicator or alarm to alert whoever is responsible for the device.

How Can You Tell if an AED Is Rescue Ready?

Most AEDs have a simple status indicator.

This may be:

• A flashing green light

• A green tick

• A green rescue-ready symbol

• A status display screen

If the device detects a problem, the indicator usually changes colour or displays a warning.

This makes it easy for routine inspections to identify potential issues.

What Actually Causes Problems?

In my experience, the biggest risks are not usually faults within the defibrillator itself.

The more common issues are:

• Expired electrode pads

• Expired batteries

• Missing accessories

• Accidental damage

• Water ingress

• Vandalism

• Lack of routine inspections

These are governance issues rather than equipment failures.

The AED itself is often perfectly functional.

What Happens in Real Life?

Over many years of servicing and inspecting community defibrillators, I've found that most devices remain remarkably reliable.

What we do occasionally discover are issues that nobody realised existed.

Perhaps a battery has reached its expiry date.

Perhaps the pads have quietly expired.

Perhaps a status light has changed colour and gone unnoticed.

These are exactly the sort of problems that regular inspections are designed to identify before an emergency occurs.

Why AED Governance Matters

Installing a defibrillator is only the beginning.

The real challenge is ensuring that the device remains rescue ready year after year.

Questions every AED guardian should ask include:

• Who checks the AED?

• How often is it inspected?

• Who tracks battery expiry dates?

• Who monitors electrode expiry dates?

• Who ensures the device remains registered and accessible?

Without clear ownership, even the best AED can become neglected.

What About Community Defibrillators?

Most community AEDs are owned by organisations such as:

• Parish councils

• Sports clubs

• Schools

• Churches

• Businesses

• Community groups

These organisations usually have volunteers or staff members who help oversee the equipment.

Many also choose to use professional aftercare services to ensure inspections, consumable replacements, reporting, and governance are managed correctly.

Should I Worry About Using a Public AED?

No.

If you need a public access defibrillator during an emergency, use it.

Modern AEDs are designed to alert users if a problem exists.

The vast majority are ready to perform exactly as intended.

The greater risk is hesitation.

The greater risk is deciding not to use an AED because of concerns that may not exist.

Final Thoughts

Let's put this myth into perspective.

Public access defibrillators are not fragile devices waiting to fail.

They are robust, highly reliable pieces of lifesaving equipment designed specifically for use in emergencies.

Like any safety equipment, they benefit from proper maintenance and oversight.

When looked after correctly, they stand ready to help save lives for many years.

If you ever need one, don't be afraid to use it.

The device has been waiting for that moment.

About Ken Hopkins

Ken Hopkins is an AED expert with more than 40 years' experience in defibrillation, multiparameter monitor defibrillators, pre-hospital ECG telemetry, community AED governance, training, and support.

Need advice about community defibrillators, governance, training, servicing, or AED Aftercare?

Hopkins⁺ Training and Support is always happy to help.