How can the hydrogen sector safely address explosion risks?

As the hydrogen industry is set for growth the risks alongside it are being watched with stern eyes, Hydrogen Industry Leaders spoke with Rhino Hysafe to understand how we can mitigate the risks associated.

As the world transitions towards a sustainable future, the hydrogen industry is poised for significant growth, with product development and technological advancements increasing.

However, with the inherent flammability of hydrogen and recent explosions over the years, addressing the risks has emerged as a challenge for the sector. 

Hydrogen can be explosive at concentrations of 18.3- 59%. Although this represents a large range, it can come with potentially dangerous outcomes. Bodies involved in storing hydrogen must maintain awareness with handling of the gas as continued releases in a conducive scenario can create a chain of harmful overpressure.

In response to the “challenges posed by hydrogen’s flammable characteristics”, Rhino Hysafe, a subsidiary of the Rhino Engineering Group, is offering a solution to an unheeded issue in the sector.

Through its design and engineering team, the company was able to patent products which could help alleviate the deflagration-to-detonation properties of hydrogen.

The manufacturer has developed a range of explosion vents with the aim to create a “passive, and safe path” through which blast overpressure and flames may be directed to before damaging equipment, buildings or people.

Ventilation as a protection method

According to the Department of Energy, for hydrogen to pose a fire hazard, it “must be confined.” 

Due to its high diffusivity rate, hydrogen can quickly dilute into a non-flammable concentration when exposed to air under the right conditions. However, when hydrogen is confined in an enclosure, the risk of dangerous pressure buildup increases, turning a potentially harmless gas into a significant hazard.

This is where Rhino Hysafe’s explosion relief panels come in. Designed to safely vent excess pressure and direct explosive blasts in a controlled manner, the panels offer a critical solution for preventing catastrophic outcomes from hydrogen buildup. 

The HySafe VERTEX vent panel has been developed and tested to demonstrate its reliable and rapid activation with the product featuring a “low-inertia rapid-relief venting system” tailored explicitly for hydrogen applications.

By creating a “safe path for pressure relief”, Rhino Hysafe is addressing a key gap in the market, helping companies “protect their workers and assets from hazardous environments”.

Speaking to Stuart Lawrence, the Group managing director for Rhino Engineering Group, Hydrogen Industry Leaders gained a deeper insight into how the product works and how Rhino Hysafe are helping the industry tackle this vital safety issue.

Designing and testing for an “optimal” performance

Through its vigorous testing process Rhino Hysafe were able to provide a product which can sustain a wide range of overpressure and impulse conditions. 

The company outlined its development process, which began by outlining analytical methods and conducting simplified preliminary tests, allowing for the “creation of a convenient pressure-impulse curve”.

With the success of initial testing processes, this paved the way for explicit finite element analysis (FEA), which was carried out prior to full-scale hydrogen deflagration testing.

Through industry aims of preventing hydrogen explosions, Rhino Hysafe noted how “effective venting is crucial while still in the early deflagration stage” to steer away from a dangerous transition to detonation.

The manufacturer took part in full-scale explosion tests in 2022 at the DNV Spadeadam site in Cumbria using their 26m3 chamber. Through its eight tests, Rhino Hysafe were able to successfully mitigate the challenges, while providing explosion relief vents that “perform reliably under the demanding conditions of hydrogen deflagrations”.

Using explosion relief panels to ensure safe hydrogen storage

The explosion relief panels are mounted on standardised containers housing hydrogen processing equipment, with apertures along the roof allowing for optimal venting. This design ensures that “pressure is released safely”, while accounting for the possibility that the enclosure may not withstand an explosion.

Lawrence explained how the product targets a “pressure build up” forcing the panels to open “allowing the blast to be vented in a safe direction before it gets too high”. 

“It opens very quickly to make sure the pressure inside doesn’t get up to an unmanageable level” -Stuart Lawrence

The hope for Rhino Hysafe remains that the product “will stay in place as part of the enclosure and hopefully is never used, just sitting there unless the worst happens”.

“The purpose of this is, like, I say, is a relatively cheap and passive system, so it’s weatherproof, but it opens very quickly to make sure the pressure inside doesn’t get up to an unmanageable level” explained Lawrence.

Rhino Hysafe’s product is specifically designed to fit standard ISO container installations, meeting the requirements of ISO 19880-1 and in accordance with NFPA 68, for easy integration and industry compliance.

In addition to its container panels (VERTEX-1), Rhino Hysafe has released its VERTEX-4, 6, and B panels which are wall or roof mounted and can be suitable for buildings for hydrogen processing and storage.

The misconceptions of hydrogen safety within the industry

As the hydrogen industry grows, as does the need to ease hydrogen safety practices and the need to implement these into everyday operations.

Common misconceptions surrounding the handling and safety measures of hydrogen can lead to inadequate safety protocols with misconceptions hindering the industry’s growth and safety in the future.

“A misconception of hydrogen safety is that you don’t have a choice in how to deal with it” – Stuart Lawrence

When exploring the misconceptions across hydrogen safety, Lawrence highlighted that one of the main misconceptions comes with a lack of choice across the industry.

“I think the misconception is that you don’t have a choice in how you deal with this, the safety aspect of it. It seems to us that the method of dealing with the risk of leaks from equipment in an enclosure is to try and detect the leak and try and keep the concentration levels down. But you know, the misconception really is, that that’s the only way”.

Many of the current safety systems focus on the detection of leaks and the maintenance of keeping concentration levels low but Rhino Hysafe are keeping the focus on the issues that remain at large.

Through adopting a more holistic approach that recognises the full spectrum of hydrogen risks and implements proactive safety measures, like explosion relief panels, companies can prevent catastrophic events before they happen.

With the right safety measures in place, the hydrogen sector can continue to grow confidently, knowing that safety is at the forefront of its development.