Safety in industrial plants handling flammable substances is a top priority for every company in the energy sector.
In hydrogen production and distribution plants in particular, the accurate classification of ATEX zones is a key element in ensuring operational safety and regulatory compliance.
The classification of hazardous areas requires specialised technical expertise and adequate knowledge of the relevant regulations. At Simplifhy, we conduct in-depth technical studies analysing every aspect of plant safety, including ATEX zone classification.
Reference framework of the ATEX classification legislation
The ATEX (ATmosphères EXplosives) legislation is the European reference for the prevention of explosions in working environments.
The European ATEX Directive 2014/34/EU (on equipment) sets out essential requirements and guidelines for safety in places where explosive atmospheres may occur.The European ATEX Directive 2014/34/EU (on equipment) sets out essential requirements and guidelines for safety in places where explosive atmospheres may occur.
In Italy, the classification of hazardous areas follows the standards CEI EN IEC 60079-10-1:2023 for flammable gases and vapours and CEI EN 60079-10-2:2016 for combustible dusts. These standards provide methodological criteria for identifying and classifying areas where explosive risk conditions may occur.
In particular, CEI EN IEC 60079-10-1:2023 deals with the classification of places where dangers associated with the presence of flammable gases or vapours may occur and serves as a basis for the correct design, construction, selection and maintenance of equipment for use in a hazardous area.
The correct application of the ATEX regulations in systems operating with hydrogen is particularly important, considering the specific physical-chemical properties of this gas, characterised by a wide flammability range and low minimum ignition energy.
The ATEX classification: types and characteristics of zones
The ATEX classification divides hazardous areas into specific zones, differentiated according to the frequency and duration of the presence of an explosive atmosphere.
In particular, for flammable gases and vapours, the classification provides for three main types:
- Zone 0: areas where an explosive atmosphere is present continuously, for long periods or frequently. These zones require the highest safety measures and the use of equipment with a very high level of protection.
- Zone 1: areas where an explosive atmosphere may occur occasionally during normal operation of the plant. The probability of formation is lower than in Zone 0, but still requires significant protective measures.
- Zone 2: areas where the explosive atmosphere may occur infrequently and only for short periods, generally under abnormal operating conditions (in the event of leaks or faults). It represents the lowest risk level among the classified zones.
In hydrogen production and distribution plants, the correct identification of these zones allows appropriate safety measures to be implemented and certified equipment to be selected for each operating environment.
Assessment parameters for ATEX classification
The ATEX zone classification methodology is based on the analysis of several fundamental technical parameters. The identification of representative substances is the first step in the analysis, considering all flammable gases, liquids and dusts present in the plant or generated by production processes.
The assessment parameters for classification include the so-called “boundary conditions”, i.e. the specific circumstances that influence the formation and duration of explosive atmospheres:
- characteristics of the working environment
- presence of natural and artificial ventilation
- process values such as temperature and pressure
- operating mode of the plant.
For each representative substance, emission sources are identified and a thorough analysis is carried out for each of them.
First, a quantitative estimate is made of the flow rate of flammable gas or vapour emitted according to the type of emission. In addition, an assessment is made of the ventilation conditions in the environment considered.
The combination of these elements makes it possible to precisely define the shape, extent and type of each classified zone, thus providing the technical basis for the design of installations and the definition of appropriate safety measures.
Simplifhy’s role in ATEX zone classification
Simplifhy acts as the technical partner of choice for ATEX zone classification studies in hydrogen plants.
In fact, we are able to produce detailed technical reports analysing all aspects of explosive safety, supporting customers and designers in the design phase.
Our experience in various projects for Hydrogen Valley, industrial plants and hydrogen filling stations enables us to provide highly specialised technical advice.
Our studies strictly follow the CEI EN IEC 60079 standard and industry specifications, ensuring regulatory compliance and optimisation of technical solutions.
Our support during the ATEX zone study phase includes the complete analysis of emission sources, the assessment of operating and environmental conditions and the definition of risk mitigation strategies. This methodological approach ensures safe and efficient installations, while optimising investment and operating costs.
Our technical expertise in ATEX classification is a fundamental added value for the development of the hydrogen economy, contributing to the creation of safe infrastructures that comply with stringent industry standards.
Contact us for an ATEX zone assessment of your hydrogen system.
