A recent assessment of a section of industry in Queensland identified a number of 'hazardous areas' at existing plants that had not previously been classified. As a result, it is possible that the suitability of electrical equipment installed in these areas was not assessed at the time of initial installation. In such instances, a review of existing electrical equipment is required to ensure it is compliant with any new hazardous area classification and complies with Section 7.7 of AS/NZS 3000 (the Wiring Rules).
Managing electrical safety risks
Non-compliant electrical equipment within an explosive atmosphere may generate ignition sources and increase explosion risks.
The Electrical Safety Office (ESO) considers that where an explosive atmosphere (e.g. from gases, vapours or dusts) is present or is reasonably likely to be present, then the person in control has a duty of care under the Electrical Safety Act 2002 to take steps to determine:
- those areas of a site or plant that may be affected by an explosive atmosphere
- if any existing electrical equipment or electrical installation wiring is located within an affected area,
- whether any such existing electrical equipment or installation wiring complies with the applicable standards and adequately controls risks to health and safety (e.g. avoids potential sources of ignition).
Developing an improvement plan for a new hazardous area
Where an area at an existing plant has been classified as a new hazardous area, the person in control of the plant shall carry out a review of any existing electrical installations and where required, develop a suitable improvement plan. The following steps are recommended:
Step 1: Assess the area to determine the presence of electrical equipment
When assessing an area, look for:
- socket outlets
- electrical wiring and conduits (including those that might pass through the area)
- electrical appliances (including air conditioning units)
- switchboards and control panels,
Step 2: Assess electrical equipment to determine whether it complies with the relevant equipment/installation standards
As the area has not been previously identified as a hazardous area, the electrical installation and equipment should be assessed for compliance against the current published relevant standard (a competent person with skills and knowledge is required for this step).
Step 3: Determine the level of risk posed by any existing electrical equipment
Consider the proximity of the electrical equipment to the potentially explosive atmosphere, and the likelihood of it becoming a source of ignition (for example, wiring in a conduit may not provide the same risk of ignition as a light switch).
Step 4: Based on the level of risk determined in Step 3, develop your improvement plan
The improvement plan should identify:
- all electrical equipment located within the hazardous area
- degree of risk posed by that equipment (e.g. low to high)
- proposed actions to eliminate the risk (such as re-locating the electrical equipment out of the hazardous area or replacing existing equipment with compliant equipment)
- proposed timeframes to implement any remedial action required (time frames must consider the level of risk involved),
- any interim control measures required to reduce risk until remedial action is completed (for example, can lights or socket outlets be de-energised and locked out to prevent use until they are relocated?).
Note: You must ensure that any interim control measures do not introduce other hazards and risks. For example, would disconnecting lights create fall or trip hazards due to inadequate levels of lighting?
Assessing a new hazardous area and developing any required improvement plan can be carried out by in-house staff or external consultants with experience and competencies in selecting and installing electrical equipment in hazardous areas. Examples include:
- suitably qualified electrical engineers
- licensed electrical mechanics who have completed the Advanced Diploma of Engineering - Explosion protection (UEE61211),
- ESO accredited hazardous area auditors
Organisations that may be able to provide further information can be found below.
Hazardous area installation work
Electrical work carried out as part of any improvement plan must be carried out by appropriately licensed electrical workers. If the electrical work involves hazardous area installation work, the licensed worker also needs to be trained and competent in this type of work. Master Electricians Australia (MEA) or National Electrical Communications Australia (NECA) can assist in directing you to workers with specialist knowledge and skills in hazardous area installation work.
Furthermore, section 221 of the Electrical Safety Regulation 2013 (Qld) provides that a person must not connect or reconnect an electrical installation located in a hazardous area to a source of electricity after electrical installation work has been performed on the electrical installation, unless:
- the electrical work has been inspected by an accredited auditor, and
- the accredited auditor has confirmed that the electrical installation is safe to connect.
Note: an accredited auditor cannot certify any hazardous area electrical installation that they have designed or installed. In such instances, a different accredited auditor must conduct the assessment to confirm the electrical installation is safe to connect to supply.