So you think you have a hazardous area?

We are often approached by clients who have just discovered (or been informed about) the world of hazardous areas. Typically an electrician or regulator has noticed that they handle flammable materials and asked a question such as "Can I see your HA verification dossier?" or "What is the hazardous area classification?" Alternatively, a contract or specification has called for a hazardous area verification dossier to be supplied.

This leads to enquiries such as "Can you supply me a HA verification dossier?". Unfortunately, the dossier is only a compilation of the various bits of design and compliance documentation that are needed to install or maintain equipment in a hazardous area.

The various steps to HA compliance for a new site are outlined in this post. These steps are equally valid for an existing site looking to bring their installation into compliance.

E-x Solutions can assist you with all of these steps, to ensure a safe and compliant installation.


The first step is for a competent person to complete a hazardous area classification to identify where explosive atmospheres are likely to occur continuously, in normal operation, or in expected abnormal operation.

Classification is required for any site that stores, handles, produces, or otherwise processes flammable gases, flammable liquids, or combustible dusts.

It is important to note that a classification of non-hazardous is a perfectly valid outcome from a properly done hazardous area classification. We strive to look for practical steps our clients can take to reduce or eliminate their hazardous areas.

A report detailing the classification methodology and decisions made to arrive at the zones is required, and drawings showing the zones are recommended.

Equipment selection, installation, and initial inspection

Any electrical equipment to be installed in the classified hazardous areas needs to be suitable for the Zone or EPL, Equipment Group, and Temperature Class set out in the HA classification. Ex electrical equipment needs certification, see this post for more information on the Australian requirements.

The equipment selection and installation design needs to be completed by a designer competent to work on hazardous area installations.

The equipment needs to be installed by an installer competent to work with Ex Equipment.

Before being put into servce, an initial inspection at a detailed grade needs to be completed according to AS/NZS 60079.14 by a competent inspector.

There is no requirement in AS/NZS 60079.14 for independence between the designer/installer/inspector and they can all be the same person.

Requirements for competency can be found in AS/NZS 60079.14. Competency requirements can be satisfied by review of the design or installation.

Regulatory inspections

In some jurisdictions a regulatory inspection or audit is required in addition to the initial inspection per AS/NZS 60079.14. This must be completed by an independent person who has not been involved in the design or installation.


For Victoria, installation of equipment which operates at LV or above in a hazardous area is prescribed work and must be inspected by a Class “H” licenced electrical inspector.


For Queensland, any installation of electrical equipment in a hazardous area must be inspected by a hazardous area installation auditor appointed by the Electrical Safety Office.


For Tasmania, any installation of electrical equipment in a hazardous area must be notified to the appointed Electrical Safety Inspection Service on behalf of the Department of Justice.

Verification Dossier

The HA classification and details of the selected electrical equipment and installation need to be recorded in a hazardous area verification dossier.

The dossier needs to be updated over the life of the installation. Records of periodic inspections, any equipment maintenance or repair, and any changes to the HA classification or installation need to be included.

Maintenance and periodic inspections

The equipment needs to be maintained in accordance with AS/NZS 60079.17, including periodic inspection by a competent person at least every 4 years for all fixed electrical equipment. More regular inspection is required for portable equipment.