HAZARDOUS AREAS EXPLAINED: PART 2 – MANAGING HAZARDOUS AREAS

The following article has been authored by Brad Guy of Bluefield Compliance

Hazardous areas can sometimes appear to be an area of ambiguity and mystery for some.

In Part 1 of our series, we defined a Hazardous Area.

Here in Part 2, we’ll outline the requirements for managing Hazardous Areas.

➡ Hazardous Areas Defined: Part 1 – Explaining Hazardous Areas

Bluefield is passionate about equipment that operates reliably, at the lowest cost per tonne, and at reduced risk for clients in the mining, gas and transport industries.

The Bluefield specialists assist our clients to overcome the following:

Stress that comes from unreliable equipment
Unwanted calls from the site at night and on the weekend due to unscheduled events
Meetings to review maintenance budgets or production targets that are not on target
Asset replacement decisions that are not optimal for the business bottom line
Risk or uncertainty over asset integrity that could lead to catastrophic equipment failures

VERIFICATION DOSSIERS
A Verification Dossier is defined, according to IEC 60079.14 Edition 5 2013-11, as a:

Set of documents showing the compliance of electrical equipment and installations.

Therefore, all electrical equipment that is to be installed in a hazardous area will need to be manufactured to a certain standard along with the electrical design of the installation.

Once a manufacturer develops a product, a sample of the equipment is to be sent to a Testing Laboratory (of which there are three acceptable Testing Laboratories in Australia) where they will put the equipment through a rigorous testing procedure. If the equipment satisfies these tests, results of the testing are then sent to the Certification Body that will Certify the equipment and issue a “Certificate of Conformity” for the equipment.

The ATEX equipment 2014/34/EU was put into place to remove barriers to trade by ensuring that the quality of equipment manufactured within the EU met rigorous essential safety requirements. The second ATEX directive is the 1999/92/EC which is a Workplace Directive that addresses safety where there is danger from potentially explosive materials.

These are directives and must be followed throughout the EU.

All documentation in relation to the hazardous area needs to be retained and kept as a live document – this collection of documentation is called the Hazardous Area Verification Dossier.

This can come in several different forms: hard copy, electronic copy, or the software tools that have been created in alignment with IEC 60079.17 Edition 5 2013-11. The software can be used to retain information, carry out inspections and highlight non-conformances and upcoming inspections. The dossier must be accessible to all those on-site working within or related to the hazardous area.

The following is an example of the process to be carried out in relation to developing compliant hazardous areas along with documentation that needs to be retained and included in the Hazardous Area Verification Dossier to maintain compliance.

CLASSIFICATION OF HAZARDOUS AREAS
When a hazardous area is present or may be expected to be present, the first requirement is to complete a basic general arrangement design of the plant. From this design certain information is required to be able to perform a Hazardous Area Classification.

General arrangement drawings
Flammable gas, vapour
Possible sources of release of vapours
The hazardous area classification needs to be carried out to IEC 60079.10.1 by an electrical engineer with the required competency.

The hazardous area classification is a study on the flammable gases and possible sources of release which will determine the “Zonal extents” as a Zone 0, 1 or 2 (for flammable gas atmospheres) or Zone 20, 21 or 22 (for combustible dust atmospheres).

This restricts electrical equipment including lighting systems that can be installed in or enter these Zones (permanent, portable, transportable and personal).

The classification will also determine the gas group which determines how easily the gas can be ignited by “spark”.

There are 3 gas groups IIA, IIB and IIC, (IIC being the most easily ignitable) or on the case of combustible dust groups IIIA, IIIB or IIIC (IIIC being the most onerous).

The classification will also determine temperature class (T-Class) which will determine how easily the gas can be ignited by “temperature”. There are 6 temperature classes T1, T2, T3, T4, T5 and T6, (T6 being the most easily ignitable) these are dependent on ambient temperatures. In the case of dust, the ignition temperatures of the dust is considered for both a layer of dust and a cloud of dust and given as a temperature.

A flammable gas or combustible dust table will be created, giving properties of all flammable or combustible material found on site.

A source of release table showing all possible sources of release and other information such as Grades of release and zonal extents explained.

A Hazardous Area Classification Schedule is then created, which will include the previous tables mentioned in report form and hazardous area drawings drafted from information entered into the source of release table showing zonal extents gas or dust group and temperature class.

These drawings should be available in both plan and elevation.

As a plant increases in age, some things change that may include

Buildings erected or demolished
Changes to the process
Changes to chemicals used
Any of these may alter the original classification and require a review from a competent person as mentioned previously.

It is for this reason that it is recommended to have a review of the classification carried out on a regular basis to ensure safety, compliance and efficiency.

HAZARDOUS AREA ELECTRICAL DESIGN
Once the Hazardous Area Classification has been completed, the electrical design can be refined into suitable “certified” electrical equipment for that hazardous area.

All electrical equipment is required to have certification from an accepted certification scheme as previously mentioned.

Throughout the EU Hazardous Area Design must follow the ATEX directives

IEC is an international certification scheme that is accepted in all participating IEC member counties

In Australia, only equipment with a Certificate of Conformity under the ANZEx (previously AUS Ex) or IECEx scheme is suitable for installation within Australia (ATEX is not accepted).

Equipment certified to alternate foreign schemes may be accepted after a Conformity assessment or Fitness for purpose assessment has been completed for that equipment for it to be installed on that site under certain conditions.

The hazardous area electrical design needs to be carried out to IEC 60079.14 by an electrical engineer holding the required competency.

HAZARDOUS AREA ELECTRICAL INSTALLATION
Electrical equipment needs to be selected and installed according to the hazardous area electrical design.

The hazardous area installation is an electrical installation and still needs to be installed and tested in accordance with all electrical acts and regulations for the country as well as the latest edition of the hazardous area standard IEC 60079.14

The hazardous area installation needs to be installed by an electrician holding the required competency.

HAZARDOUS AREA ELECTRICAL MAINTENANCE

Maintenance for the hazardous area electrical installation needs to be carried out to the version of IEC 60079.17 to which it was installed and carried out by an electrician holding the required competency.

HAZARDOUS AREA ELECTRICAL TESTING

The hazardous area electrical installation needs to be tested to IEC 60079.14 by an electrician holding the required competency.

HAZARDOUS AREA ELECTRICAL INSPECTIONS
Once the installation has been completed the hazardous area electrical installation is required to have an “Initial Detailed Inspection” carried out.

Once the equipment is in service, ongoing periodic inspections are required to take place that can be completed as a visual inspection which is considered as a “hands in pockets” inspection, where the inspection is completed without tools or access equipment, or as a close grade inspection, which allows for the use of tools and access equipment and covers all aspects of a visual inspection with extra checks.

All inspections need to be compliant to the version of IEC 60079.17 to which the equipment was installed.

The inspections are to be carried out by an electrician holding the required competency.

In Australia, all Victorian hazardous area installations require an inspection carried out by an electrician holding the “H” class endorsed Victorian electrical licence.

NOTE: The hazardous area electrical inspector should be independent of the installation and maintenance personnel.

The hazardous area electrical inspectors do not need to be from a different company.

HAZARDOUS AREA ELECTRICAL AUDITS
In the State of Queensland, the Electrical Safety Act requires that all “new” hazardous area installations within Queensland require a Hazardous Area Audit completed on the entire installation after the installation has been completed.

The audit is required to be carried out prior to energisation of equipment and circuits within the hazardous area.

The auditor needs to be accredited by the Department of Justice, Electrical Safety Office to carry out electrical hazardous area audits for that category: –

Category A – flammable gases and liquids
Category B – combustible dusts
Category C – flammable gases, liquids and combustible dust
The audit will be carried out looking at classification, design, installation, maintenance strategies and information held in the verification dossier.

A list of accredited hazardous area auditors can be found on the Department of Justice website.

CONCLUSION
The information contained here is basic information only to give people a better understanding of requirements for hazardous areas.

Every situation is different and needs to satisfy the following: –

Relevant ACT’s and regulations
Relevant standards
Individual country requirements
Individual State requirements
Site policy and procedures
Some people find standards ambiguous or difficult to interpret but most in most instances the requirements and intent can be worked out without ambiguity.

ABOUT THORNE & DERRICK
Thorne & Derrick International, based in the UK, are Approved Vendors to most Oil & Gas exploration and production companies and international EPC contractors including Bechtel, Petrofac, Saipem and Lamprell – our key sectors are the mining, process, pharmaceutical, chemical, utility, food/beverage, renewable and oil/gas industries.

We contribute strategic and added-value to the supply chains of the global chemical processing and energy sectors via our memberships of North East of England Process Industry Cluster (NEPIC) and NOF.

We are the Explosive Atmosphere Experts to COMAH-site operators providing innovative and often customised Ex solutions engineered to improve site safety and reliability.

THORNE & DERRICKHazardous Areas Specialists
LV HV Electrical & Process Instrumentation Equipment for Explosive Atmospheres

Specialist Distributors of Hazardous Area & Explosion Proof Equipment with IECEx & ATEX Certifications – we react with a rapid response to your enquiry to ensure downtime is minimised and reliable Power, Light & Heat is restored or provided.

External URL: https://www.heatingandprocess.com/hazardous-areas-explained-managing-hazardous-areas/

By Thorne & Derrick International

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