This bulletin presents WorkSafe’s position on notification following failure, operation or activation of a rupture disc classified as a safety critical element (SCE) at a Major Hazard Facility or Petroleum Installation.

WorkSafe's position 

If a rupture disc activates, and has been classified as an SCE by the operator, WorkSafe must be notified of the activation under the MHF Regulations r33(c) and/or PEE Regulations r70(f).


There has been some uncertainty regarding reporting of rupture disc (or ‘bursting disc’) activation.

By design, a rupture disc is a safety device with a onetime-use membrane that ruptures at a predetermineddifferential pressure, either positive or vacuum. This can be referred to as failure, operation, rupture or burst,
or activation of the device.

When the device ruptures, it requires replacement. The replacement rupture disc serves the same one-off safety function once the process is returned to service.

This technical bulletin advises when a rupture disc activation is notifiable to WorkSafe under the:

The regulations

A rupture disc could be classified as an SCE at a Major Hazard Facility or Petroleum Installation.  

The definition of a safety critical element is covered within MHF Regulations r4 and the PEE Regulations r3(1).

Additional guidance for MHF operators on identifying safety critical elements is available in the:

The notification requirements for safety critical element (SCE) failures are covered within the MHF Regulations r33(c) and the PEE Regulations r70(f).

Notification requirements

Operators (including drilling contractors) must comply with requirements in:

  • MHF Regulations r34 and Parts 1 and 2 of Schedule 4, or
  • PEE Regulations r71 and Parts 1 and 2 of Schedule 9.

The root cause analysis required in each Part 2 should be proportionate to the severity/complexity of the rupture disc activation.

If you are not sure whether notification is required, the best course of action is to contact WorkSafe.


Technical bulletin: Notifying a rupture disc activation when classified as a SCE (PDF 46 KB)