How PEM electrolysers support safe hydrogen production
- PEM electrolysers use a solid polymer membrane to keep hydrogen and oxygen streams separated, helping reduce cross-contamination risk during electrolysis.
- Gas monitoring systems can detect hydrogen concentrations and trigger alarms or automatic shutdowns at configured thresholds.
- Standards such as AS 22734:2020 and ISO 22734-1:2025 guide hydrogen-generator design, while project compliance also depends on local regulations, approvals and site-specific risk controls.
- Electrolysers, such as Endua's PEM electrolysers, are pre-engineered and factory-tested, with gas monitoring devices and compliance with relevant Australian Standards incorporated into each unit.
- Layered safety measures such as pressure relief, ventilation and electrical isolation help protect people and equipment during normal and fault conditions.
Producing hydrogen on-site requires careful engineering and reliable process controls. If you’re evaluating PEM electrolysers for on-site hydrogen production, understanding how it manages hydrogen hazards can help you plan your project more confidently.
On-site hydrogen generation can give your organisation greater control over production conditions and safety parameters, with less reliance on complex off-site supply chains. In this article, we explore the system features, monitoring processes and operational practices that support safe, compliant hydrogen production.
How does PEM electrolyser technology support safer hydrogen production?
PEM, or Proton Exchange Membrane, electrolysis uses a solid polymer electrolyte membrane to conduct protons from the anode to the cathode. The membrane also creates a physical barrier between the hydrogen and oxygen produced when water is split.
By separating the gas-producing compartments, the membrane helps reduce the likelihood of hazardous gas mixtures. This separation still depends on the membrane, seals and controls remaining within their specified operating conditions, and monitoring remains an important part of the system.
In some designs, the membrane allows the hydrogen and oxygen sides to operate at different pressures. This can reduce compression requirements, although additional mechanical compression may still be required to reach the chosen delivery or storage pressure.
PEM systems can also respond quickly to changes in input power, making them well suited to variable renewable energy sources. Some systems can adjust hydrogen production as renewable power availability changes, within the equipment’s specified operating limits.
How do PEM electrolysers manage hydrogen hazards?
Hydrogen is flammable at concentrations of 4% to 75% in air, and its flames can be difficult to see. Managing these characteristics relies on several detection, control and response measures working together.
Gas detection and monitoring
An industrial electrolyser installation may use gas-detection sensors near potential leak sources and in areas where hydrogen could accumulate. A site risk assessment and applicable requirements guide where these sensors are placed.
Hydrogen sensors can continuously measure concentrations and send alarms or operating data to a local or remote monitoring system. Detection thresholds are set for the individual installation and may prompt responses such as:
Alarm set-points: These may be expressed as a percentage of the hydrogen lower explosive limit (LEL).
Emergency or evacuation actions: These responses are set out in the site-specific emergency plan and linked to the installation’s risk assessment.
Automatic shutdown set-points: The system design and risk assessment determine these thresholds. A shutdown may stop further hydrogen production, but it cannot remove gas that has already accumulated.
Managing cross-contamination risk
Monitoring for hydrogen in oxygen streams and oxygen in hydrogen streams is an important safety check in an electrolyser. Cross-contamination can create hazardous conditions if gas concentrations move beyond the system’s specified limits or the gases encounter an ignition source.
Endua’s PEM electrolyser, for example, continuously monitors gas purity to confirm that the membrane is separating the gases as intended. This can help identify crossover or other abnormal operating conditions.
What safety standards apply to industrial hydrogen electrolysers?
The standards, laws, approvals and site requirements that apply to an electrolyser project depend on its jurisdiction. Understanding these requirements can help you evaluate equipment and plan a safe, compliant deployment.
ISO 22734 series
ISO 22734-1:2025 sets international requirements for hydrogen generators that use water electrolysis. It covers safety considerations relating to construction, testing and installation.
The adopted edition sets out provisions for indoor and outdoor installation, ventilation, detection and emergency shutdown. Additional requirements for hazardous areas, electrical systems and pressure equipment vary by project and jurisdiction.
Meeting ISO 22734 can demonstrate alignment with an internationally recognised safety standard. It does not replace local approvals, a site-specific risk assessment or appropriate operational controls.
Australian Standards and local compliance
In Australia, AS 22734:2020 aligns with the international ISO standard while incorporating region-specific requirements. Other relevant considerations include hazardous-area classification under AS/NZS 60079 and pressure-equipment compliance under AS 4343.
Did you know?
Endua electrolysers are designed to relevant Australian and International Standards and include gas monitoring devices as standard equipment. Endua’s initial demonstration system in 2023 was the first product to comply with Queensland’s new Hydrogen Safety Code of Practice.
What operational controls support safe hydrogen production?
Standards and system design lay the groundwork for safety, while day-to-day operations shape how those protections perform in practice. This includes how your team monitors the system, maintains equipment and prepares for emergencies.
Daily and periodic inspections
Daily operational checks may cover gas detector function, ventilation, pressure readings and any signs of leaks or abnormal conditions. The manufacturer and your site safety documentation typically set the inspection schedule. Periodic checks may review electrical connections, pressure-relief systems and emergency shutdown functions.
Audits may also include system testing, safety-procedure reviews and checks against current standards. Their frequency depends on applicable requirements and the site risk assessment. Your project’s jurisdiction or risk assessment may also call for an independent assessor.
Remote monitoring capabilities
Some modern electrolyser systems offer remote monitoring, so your team can review performance without being physically present. Endua systems support back-to-base communication, allowing your team to monitor performance and control the system from a central location.
By tracking operating data over time, remote monitoring can support predictive maintenance. Changes from normal operating patterns may point to a developing issue before it becomes a safety concern.
How does layered protection support electrolyser safety?
Safety rarely depends on one feature. Industrial hydrogen systems typically use several independent protection layers so that another safeguard can help reduce the consequences if an earlier layer fails.
Key terms:
HAZOP: Hazard and Operability Study
LOPA: Layer of Protection Analysis
SIF: Safety Instrumented Function
SIL: Safety Integrity Level
The HAZOP and LOPA framework
A HAZOP study helps your project team identify how operation could move away from normal conditions and what the consequences may be. A LOPA then helps assess whether the system requires additional independent protection layers or safety instrumented functions (SIFs). It can also contribute to setting a target SIL under the relevant functional-safety method.
SIL ratings range from SIL 1, the least stringent, to SIL 4, the most stringent. The rating indicates the required reliability of a specific safety function. Based on IEC 61508, this framework helps project teams design, verify and maintain safety functions that provide the required level of risk reduction.
Physical and procedural barriers
Physical protection layers may include pressure relief valves, rupture discs, flame arrestors and containment systems. Electrical isolation and suitable hazardous-area equipment help control potential ignition sources where hydrogen may be present. The area’s hazard classification determines which equipment is suitable and which standards apply.
Procedural protections may include operator training, permit-to-work systems and emergency response protocols. Together, these physical and procedural measures help address several possible failure scenarios.
What training supports electrolyser safety?
Training for people who work with electrolyser systems typically covers hydrogen properties, electrical safety, emergency procedures and system-specific operation. Depending on the role, a program may combine technical instruction with supervised, hands-on experience.
The right training duration depends on the operator’s role, the system’s complexity, the manufacturer’s requirements and applicable competency rules. Topics may include hydrogen safety fundamentals, electrical hazard recognition, use of safety equipment, emergency procedures and maintenance safety.
The site’s safety-management system and applicable requirements determine the schedule for refresher training, emergency drills and procedure updates. Regular drills can help your team maintain response readiness and identify opportunities to improve.
How can pre-engineering reduce deployment risk?
Traditional hydrogen projects can involve extensive custom engineering, on-site assembly and lengthy commissioning periods. Completing more work on-site can introduce extra variables and increase the risk of construction errors. Pre-engineered systems can reduce the amount of custom integration and assembly required at the project site.
Endua electrolysers, for example, arrive as pre-engineered and factory-tested units with their components already integrated. At Archerfield Airport, Endua’s pre-engineered approach reduced the installation phase from months to hours.
A full project deployment, including site preparation and commissioning, typically takes 4 to 8 months, compared with 18 to 36 months for a traditional engineering, procurement and construction (EPC) project.
Factory testing under controlled conditions can identify potential issues before the equipment reaches your site. This approach can reduce on-site assembly and construction risks. Site installation, commissioning and integration still involve controlled verification.
What ventilation requirements apply to electrolyser installations?
Adequate ventilation can limit hydrogen accumulation from minor leaks when it is correctly designed, maintained and supported by detection and shutdown controls. Appropriate ventilation capacity can help keep hydrogen concentrations well below hazardous levels.
Design standards typically base ventilation capacity on the system’s maximum hydrogen production rate. Natural or mechanical ventilation may be appropriate, while enclosed or higher-risk installations may call for mechanical ventilation and backup arrangements.
These requirements influence site selection and installation planning. Outdoor-rated systems, such as Endua electrolysers, can make use of natural ventilation, with mechanical backup available for enclosed configurations.
Deploying hydrogen safely in industrial settings
Safe industrial hydrogen production brings together well-integrated systems, relevant standards and strong operating practices. PEM electrolysers use membrane separation as one safety feature, while monitoring and layered controls help address the hazards identified in your project’s risk assessment.
Understanding the standards, monitoring requirements and operational controls can help you evaluate systems and plan your deployment with confidence. Pre-engineered, factory-tested systems can also reduce deployment risk and help your project reach operation sooner.
If you’re evaluating on-site hydrogen production for your operations, talk to Endua about your site requirements and how our PEM electrolyser technology can support safe, compliant hydrogen generation.
FAQs about how PEM electrolysers support safe hydrogen production
What is the main safety advantage of PEM electrolysers over other electrolyser types?
PEM electrolysers use a solid polymer membrane that physically separates hydrogen and oxygen during production. This barrier helps limit hydrogen-oxygen mixing, although crossover remains possible and relies on effective monitoring and controls.
How do gas detection systems reduce hydrogen risks?
A site risk assessment guides where gas detectors are installed. These devices can continuously monitor hydrogen concentrations and trigger alarms, emergency procedures or shutdowns at predefined, site-specific thresholds. A shutdown may limit further hydrogen production, but additional measures may be required to address gas that has already accumulated.
Which standards apply to industrial hydrogen electrolysers?
Applicable standards and legal requirements depend on the project’s location. In Australia, AS 22734:2020 is the relevant listed Australian Standard. India’s National Green Hydrogen Mission lists IS 16509:2020, which is based on ISO 22734:2019.
Australian projects may also refer to standards covering hazardous-area classification, including AS/NZS 60079, pressure equipment under AS 4343 and electrical safety under IEC 60204-1. Endua electrolysers comply with relevant Australian Standards.
How does Endua support electrolyser safety?
Endua electrolysers are pre-engineered and factory-tested at our facility in Archerfield, Queensland. Each system includes gas monitoring devices and complies with relevant Australian Standards. Endua has experience navigating complex regulatory environments, as shown by receiving regulatory approval under Queensland’s Hydrogen Safety Code of Practice.
What is a Safety Integrity Level and why does it matter for hydrogen systems?
A Safety Integrity Level (SIL) indicates the required reliability of a specific safety function, with levels ranging from SIL 1 to SIL 4 under IEC 61508. A higher SIL represents a greater required level of reliability. IEC 61508 provides a framework for designing and maintaining safety functions that deliver the required level of risk reduction.
How often are electrolyser safety systems inspected?
Regular checks typically cover gas detector function, ventilation and pressure readings. Periodic inspections may also review electrical connections and emergency shutdown functions. The manufacturer, site risk assessment and applicable requirements determine the intervals.
Audits may include system testing and compliance verification. Some projects or jurisdictions may also call for an independent assessment.
Can electrolysers operate safely in sensitive environments?
Some properly assessed and approved systems can operate in sensitive environments, including critical facilities. Suitability depends on the site’s environmental conditions, safety requirements and emergency plans.
Endua systems support safe operation through features such as remote monitoring and quiet operation. Their outdoor-rated design and gas monitoring can support deployment across a range of approved sites.