Gas detection standards have been developed to help protect people, equipment and facilities from the risks associated with flammable, toxic and oxygen-deficient atmospheres.
For businesses operating in hazardous environments, understanding these standards is important when selecting, installing and maintaining gas detection equipment. The correct equipment must be suitable for the environment it is being used in and meet the relevant safety, certification and regulatory requirements.
This guide will cover:
- Why gas detection standards matter
- What hazardous areas are and how they are classified
- What the IEC 60079 series is
- What ATEX is
- What IECEx is
- The differences between IEC 60079, ATEX and IECEx
- How these standards relate to different industries
- The consequences of failing to meet the relevant requirements
- How Protex can help with gas detection solutions
Why Do Gas Detection Standards Matter?
Gas detection is used in a wide range of industrial environments where flammable or toxic gases may be present, or where oxygen levels could become unsafe.
In an environment containing flammable gases or vapours, an ignition source can potentially lead to a fire or explosion. The basic principle is often explained using the “fire triangle”, where fuel, oxygen and an ignition source are required for combustion.
Gas detection can help identify hazardous conditions before they develop into a more serious incident. However, the detection equipment must be suitable for the application, correctly selected and appropriately installed.
This is where standards and regulations become important.
They provide requirements and guidance for areas such as equipment design, protection methods, hazardous-area classification, installation, inspection, maintenance and gas detector performance.
Understanding Hazardous Areas
A hazardous area is an area where a potentially explosive atmosphere may occur.
Hazardous area classification is used to assess the likelihood of a flammable atmosphere occurring and how long it could remain present. This classification can then be used when determining the appropriate equipment and protection methods for the area.
For flammable gases and vapours, hazardous areas are commonly divided into three zones:
Zone 0
An area where an explosive gas atmosphere is present continuously, for long periods or frequently.
Zone 1
An area where an explosive gas atmosphere is likely to occur occasionally during normal operation.
Zone 2
An area where an explosive gas atmosphere is not likely to occur during normal operation, but if it does occur, it will only persist for a short period.
There are also separate classifications for combustible dust:
- Zone 20 – an explosive atmosphere in the form of a combustible dust cloud is present continuously, for long periods or frequently.
- Zone 21 – a combustible dust atmosphere is likely to occur occasionally during normal operation.
- Zone 22 – a combustible dust atmosphere is not likely to occur during normal operation, but if it does occur, it will persist for a short period.
The classification of an area is important because equipment used within it needs to be suitable for the relevant hazardous environment.
What Is IEC 60079?
IEC 60079 is a series of international standards covering equipment and installations intended for use in explosive atmospheres.
The series covers different aspects of explosive atmosphere protection, including equipment design, protection methods, hazardous-area classification, installation, inspection and gas detection.
Some of the standards within the series include:
IEC 60079-0 – General Requirements
Provides general requirements for equipment intended for use in explosive atmospheres, including construction, testing and marking.
IEC 60079-1 – Flameproof Enclosures “d”
Covers equipment protected using flameproof enclosures. The enclosure is designed to contain an internal explosion and prevent the ignition from spreading to the surrounding atmosphere.
IEC 60079-2 – Pressurised Enclosures “p”
Covers equipment using pressurisation to prevent the surrounding explosive atmosphere from entering the enclosure.
IEC 60079-7 – Increased Safety “e”
Covers equipment designed to reduce the possibility of excessive temperatures, arcs or sparks occurring under normal operation and certain abnormal conditions.
IEC 60079-11 – Intrinsic Safety “i”
Covers equipment and circuits where electrical and thermal energy is limited to levels that cannot cause ignition under specified conditions.
IEC 60079-18 – Encapsulation “m”
Covers equipment where potential ignition sources are protected by encapsulation.
The series also includes standards relating to the practical use of equipment.
For example:
IEC 60079-10-1 covers the classification of areas where explosive gas atmospheres may occur.
IEC 60079-10-2 covers the classification of areas where combustible dust atmospheres may occur.
IEC 60079-14 covers the design, selection and installation of electrical installations in explosive atmospheres.
IEC 60079-17 covers inspection and maintenance of electrical installations in explosive atmospheres.
IEC 60079-19 covers equipment repair, overhaul and reclamation.
IEC 60079-29 Series – Gas Detection
The IEC 60079-29 series is particularly relevant to gas detection.
IEC 60079-29-1 covers performance requirements for detectors for flammable gases.
IEC 60079-29-2 covers the selection, installation, use and maintenance of detectors for flammable gases and oxygen.
IEC 60079-29-4 covers performance requirements for open-path detectors for flammable gases.
These standards help ensure that gas detection equipment is appropriately selected and used for the environment and application.
What Is ATEX?
ATEX is the name commonly used for the European framework covering equipment and workplaces where explosive atmospheres may occur.
There are two main ATEX directives:
ATEX Equipment Directive – 2014/34/EU
This directive applies to equipment and protective systems intended for use in potentially explosive atmospheres. It establishes essential health and safety requirements and conformity assessment procedures before products are placed on the EU market.
ATEX Workplace Directive – 1999/92/EC
This directive focuses on improving the health and safety protection of workers who may be at risk from explosive atmospheres. It includes requirements relating to the classification of hazardous areas and protection of workers.
ATEX equipment categories are linked to the different hazardous-area zones.
Generally:
- Category 1 equipment is associated with Zone 0 and Zone 20
- Category 2 equipment is associated with Zone 1 and Zone 21
- Category 3 equipment is associated with Zone 2 and Zone 22
Equipment with a higher category can also be suitable for certain lower-risk zones, depending on its certification and application.
Who Does ATEX Apply To?
ATEX requirements can affect different parts of the supply chain and workplace, including:
Manufacturers
Responsible for ensuring products meet the relevant requirements before being placed on the market.
Importers and distributors
Have responsibilities relating to the conformity and documentation of products they place on the market.
Employers and site operators
Have responsibilities for identifying and controlling workplace risks associated with explosive atmospheres.
The exact responsibilities depend on the product, workplace and applicable legislation.
What Is IECEx?
IECEx stands for the IEC System for Certification to Standards Relating to Equipment for Use in Explosive Atmospheres.
Unlike ATEX, IECEx is not a European directive. It is an international conformity assessment and certification system for equipment and other areas associated with explosive atmospheres.
The IECEx Certified Equipment Scheme provides independent assessment against relevant international standards and can result in an IECEx Certificate of Conformity.
IECEx is designed to support international acceptance of equipment that has been assessed against the relevant IEC standards.
ATEX vs IECEx vs IEC 60079: What’s the Difference?
These terms are often confused because they are closely connected, but they serve different purposes.
| IEC 60079 | ATEX | IECEx | |
|---|---|---|---|
| What is it? | A series of technical standards | European regulatory framework | International certification system |
| Main purpose | Provides technical requirements for equipment, installations and protection methods | Sets requirements for equipment and workplaces involving explosive atmospheres | Provides international conformity assessment and certification |
| Where is it used? | Internationally | EU/European regulatory framework and implemented national legislation | Internationally in participating countries |
| Certification? | Not a certification scheme itself | Can require conformity assessment and certification depending on the equipment/category | IECEx Certificates of Conformity can be issued by IECEx-approved certification bodies |
| Relationship | Provides many of the technical standards used for Ex equipment | Uses harmonised standards to support conformity | Uses relevant IEC standards as the technical basis |
In simple terms:
IEC 60079 = technical standards
ATEX = European regulatory requirements
IECEx = international certification system
Understanding the difference can make it easier to identify which requirements apply to a particular project or piece of equipment.
How Do These Standards Apply to Different Industries?
Different industries can have very different gas detection requirements.
The correct detection technology should not be selected simply because of the industry. It should be based on the specific gases present, potential release sources, environmental conditions, hazardous-area classification, ventilation, required detection performance and the risks associated with the site.
Oil & Gas
Oil and gas facilities can involve flammable and toxic gases, including hydrocarbons and hydrogen sulphide, depending on the specific process.
Applications may require technologies such as point gas detection, open-path detection, flame detection or portable gas monitoring.
The appropriate solution will depend on the facility, process and hazards identified.
Chemical & Process Industries
Chemical facilities can handle a wide variety of gases, vapours and chemicals.
Gas detection requirements can therefore vary significantly between sites. Detector selection should take into account the specific substances being used, their properties and the potential release scenarios.
Manufacturing
Manufacturing facilities can have risks associated with combustible gases, solvent vapours, toxic gases or other hazardous substances depending on the production process.
Detection systems may be used to monitor specific areas, processes or potential leak sources.
Food & Beverage
Food and beverage facilities may use gases such as carbon dioxide in fermentation and carbonation processes, while ammonia may be present in some refrigeration systems.
The appropriate detection solution will depend on the gases present and the risks associated with the particular facility.
Water Treatment
Water and wastewater treatment facilities can involve gases and chemicals that require monitoring, depending on the treatment process.
Potential applications can include monitoring for toxic gases and oxygen deficiency, with sensor technology selected according to the substance and required detection range.
The key point across all industries is that there is no single gas detection system that is suitable for every site.
A proper assessment of the application is essential before equipment is selected.
What Can Happen If the Relevant Requirements Are Not Met?
Failing to properly assess hazardous areas or select suitable equipment can increase the risk to people, equipment and operations.
There can also be legal and financial consequences when businesses fail to meet applicable health and safety or product requirements.
In the UK, for example, DSEAR requires employers to assess and control the risks associated with dangerous substances and explosive atmospheres. Where hazardous areas exist, appropriate equipment and protective measures need to be selected.
The consequences of poor risk management can include:
- Increased risk of fire or explosion
- Exposure to toxic gases
- Damage to equipment and facilities
- Production downtime
- Regulatory action
- Financial losses
- Potential legal consequences
For this reason, compliance should not simply be viewed as a box-ticking exercise. Correctly assessing the risks and selecting appropriate equipment is an important part of protecting people and maintaining safe operations.
How Can Protex Help?
At Protex, we supply gas detection solutions for a range of industrial applications.
This can include solutions using ATEX and IECEx-certified equipment, where appropriate to the application.
We also provide technical support to help customers understand their gas detection requirements and identify suitable products for their environment.
The exact equipment required will depend on factors such as the gases being monitored, the potential hazards, the location, environmental conditions and the applicable standards and certification requirements.
Conclusion
Understanding ATEX, IECEx and the IEC 60079 series is important when selecting gas detection equipment for hazardous environments.
While these terms are often used together, they have different roles:
IEC 60079 provides technical standards for explosive atmosphere equipment and installations.
ATEX provides a European regulatory framework for equipment and workplaces involving explosive atmospheres.
IECEx provides an international certification system based on relevant IEC standards.
Ultimately, selecting the correct gas detection equipment is about more than choosing a detector.
The system needs to be suitable for the specific hazards, environment and application, while meeting the relevant standards and certification requirements.
At Protex, we help customers find gas detection solutions suited to their specific requirements, helping them protect people, equipment and operations.
