A safety management system ensures so far as is reasonably practicable the gas supply system does not pose significant risk of serious harm to a person or significant damage to property.
Owners and operators of gas supply systems that supply, or are intended to supply, annual consumption greater than 10 TJ of gas per year, are required to implement and maintain an SMS.

SMSs create an environment where all aspects of the design, construction and operation of a gas distribution system are subject to third party audit and certification. This allows the owner or operator of a distribution system to fulfil their legal obligations for safety in a rigorous manner while at the same time allowing a certain amount of flexibility in their implementation.

A gas supply system is the distribution system plus any related installations, appliances and fittings that form part of a system for conveying gas to consumers (section 46A of the Gas Act).

The requirements for an SMS are stated in Regulations 32 to 40(external link).

SMSs must either comply with NZS 7901 or Regulations 33 and 34.

Requirements of an SMS

Each SMS must be fully documented and provide for the following:

• The systematic identification of hazards.
• The assessment of hazards.
• The steps to be taken to eliminate, isolate, or minimise hazards and to mitigate risks from those hazards.
• Assessment of the effectiveness of this risk management.
• Investigation of accidents.
• Enhancement of safety performance throughout the system including performance measurement.
• An audit programme.

Every SMS must be regularly audited to confirm it is being implemented and maintained in compliance with these requirements.

Operators of SMSs are required to provide WorkSafe with a statutory declaration at least once every five years to confirm the operator has a current audit certificate.

The first such statutory declaration must be made and sent to WorkSafe within six months of the first audit of the SMS.

Auditors are required to cancel the audit certificate for an SMS if the requirements for an SMS are not met, or if WorkSafe directs cancellation on the grounds that the SMS is not being implemented.

Owners or operators of other distribution systems that are not gas supply systems may opt to have an SMS in order to meet their safety obligations.

Distribution systems not covered by a Safety Management System

Distribution systems that are not covered by an SMS must meet the requirements of Regulations 25 to 28(external link). These regulations require owners and operators of distribution systems to ensure the safety of their systems by ensuring:

• Adequate records and plans are kept up to date.
• These systems are designed, constructed, maintained and operated in a manner that achieves continuity of supply and safety of the distribution systems.
• Competence of all persons who carry out work on the system and
• Regular inspections of the systems.

Compliance with New Zealand Standard NZS 5258 Gas distribution networks or Australian New Zealand Standard AS/NZS 4645 Gas distribution networks is considered to be compliant with the above regulations.