What Does the 90-Minute Emergency Light Test Actually Check?

The 90-minute emergency light test checks whether your emergency lights and battery-backed exit signs can keep operating when normal power is removed — not just whether they switch on for a few seconds. For most Australian building installations, the required in-service duration is 90 minutes, and routine service is governed by AS/NZS 2293.2:2019.

That distinction matters. A green charge indicator or a light that comes on during a quick button test can still hide a weak battery. The full discharge test is designed to expose the failures that only appear after 20, 40 or 70 minutes on battery power.

1. What Is the 90-Minute Emergency Light Test?

The 90-minute emergency light test is a controlled discharge test used to verify that emergency evacuation lighting can operate from its emergency power source after the normal electrical supply is interrupted.

In many commercial buildings, each emergency fitting contains its own rechargeable battery. When mains power is available, that battery is kept charged. When the monitored supply fails, the fitting must transfer to emergency operation so occupants can still see an escape route and identify the exits.

The routine service standard for these systems is AS/NZS 2293.2:2019 — Emergency lighting and exit signs for buildings, Part 2: Routine service and maintenance. Standards listings identify the 2019 edition as the current edition, and its purpose is to keep emergency lighting and exit-sign systems ready for operation through periodic inspection, testing and maintenance.

2. Why Does the Test Run for 90 Minutes?

AS/NZS 2293.2 requires the service technician to work from the installation’s baseline data, including its required in-service duration. In Australia, the standard points to AS/NZS 2293.1 for that duration and notes that for most situations it is 90 minutes.

The purpose is straightforward: emergency lighting is a life-safety system intended to remain available after normal lighting is lost. The test therefore has to prove endurance, not just activation.

A fitting that works perfectly for the first five minutes can still be the fitting that fails when it is actually needed.

That is why the battery is allowed to discharge for the required duration. The test creates a realistic stress condition that a short visual check cannot reproduce.

3. What Does the 90-Minute Emergency Light Test Actually Check?

A proper 90-minute emergency light test is not one single observation. It combines operational checks, a full-duration discharge and a survey of the emergency lighting and exit-sign system.

The core endurance question is simple: does each fitting continue to perform for its required duration? But the maintenance process also exists to identify visible changes and defects that can make a technically functioning light ineffective in the real building.

4. How Does a 90-Minute Emergency Light Test Work?

The exact process depends on the installation, but a well-managed commercial test generally follows this sequence.

AS/NZS 2293.2 includes service precautions before a discharge test. These include considering the effect on occupants and operations, notifying the responsible entity of the expected impairment and ensuring the installation has not had an interruption to normal supply for the prescribed period before the discharge test.

5. The Test Checks More Than Battery Life

People often describe this service as a “battery test,” but that is only part of the picture.

Does the emergency fitting activate?

A healthy battery is useless if the fitting does not transfer into emergency mode when the normal supply disappears. The service verifies that the emergency operation actually occurs.

Does it last for the required duration?

This is the part most people associate with the 90-minute test. Battery capacity deteriorates with age, temperature and service conditions. A fitting can look normal every day while connected to mains power and still fail well before the required duration once it is running from its battery.

Is the fitting still useful to occupants?

The maintenance standard includes survey activities because building changes matter. An exit sign can be electrically healthy but partially hidden by new shelving or advertising. An emergency light can still operate while a diffuser is damaged or the surrounding layout has changed.

Are previous problems actually being closed out?

Six-monthly service schedules include review of service and maintenance records. Previously recorded defects, non-conformances and observations should not simply disappear from the next report.

6. Common Reasons Emergency Lights Fail the 90-Minute Test

Many failures are invisible until the building is placed into a sustained emergency-lighting condition. Common issues include:

• Degraded batteries: the fitting activates but shuts down before the required duration.
• Charging faults: the battery has not been maintained at the charge level expected for emergency operation.
• Failed LED, lamp or driver components: battery power is present but the light source does not perform properly.
• Physical damage: cracked housings, missing diffusers, loose fittings or damage caused by impact or maintenance work.
• Blocked exit signs: stock, decorations, temporary signage or fit-out changes reduce visibility.
• Altered layouts: partitions, new corridors or room changes can affect the relationship between the system and the evacuation path.
• Poor records: fittings are missing from the register or previous failures have not been clearly closed out.
• Controls not returned to normal: after testing, test switches and system controls must be restored correctly.

This is why an emergency-lighting test should be treated as a system maintenance task, not simply as a 90-minute countdown.

7. What Happens If an Emergency Light Fails?

A failure should be recorded against the relevant fitting or system item and brought to the attention of the person responsible for the building or site.

The right response depends on the fault. Some issues may require a battery or fitting replacement; others may involve electrical work or changes to the installation. Electrical repairs and alterations should be carried out by appropriately licensed people where required.

Once corrective work has been completed, the records should show what was done and the system should be returned to a condition of readiness.

8. How Often Should Emergency Lights Be Tested?

AS/NZS 2293.2:2019 includes six-monthly routine service requirements for emergency lighting and exit-sign systems, with additional annual and longer-term activities applying depending on the installation and equipment.

For Victorian buildings, emergency lighting and exit signs can form part of the building’s essential safety measures. The Victorian Building and Plumbing Commission states that building owners have maintenance obligations for essential safety measures so they continue to operate satisfactorily.

That does not mean every property has an identical compliance schedule. The building’s occupancy permit, maintenance determination, essential safety measures schedule, baseline data and applicable Standards should be checked for the actual site.

9. What Should Be Recorded After the Test?

Good records are part of the maintenance process, not an optional extra. A useful emergency-lighting register should make it possible to understand the history of every fitting without relying on somebody’s memory.

• Unique fitting or asset ID
• Location — level, corridor, stairwell, room or relevant area
• Type — emergency luminaire, exit sign or related system item
• Service date
• Test or inspection performed
• Pass/fail result or observation
• Defects or non-conformances
• Corrective action
• Next service due

Digital records make this much easier across larger sites. Hume Test & Tag can provide clear reporting so facility managers can see what was tested, what failed and what needs attention before the next scheduled visit.

10. What Melbourne Businesses Should Know Before Booking a Test

For offices, warehouses, retail premises, hospitality venues, schools, healthcare facilities and other commercial buildings, the biggest practical issue is often not the 90-minute wait — it is planning the test properly.