While hydrogen embrittlement can occur in 49 years of research work I have yet to see it occur in room temperature operations in either brass, copper or stainless steel.

And gas detection is only a viable mitigation it the detector is placed in a suitable location (often not), covers the area of concern (often much smaller area than envisioned), calibrated routinely (2-4 months), and is not subject to being overly diluted before it can read.

These references might also help explain my concerns:

Combustible Gas Detection and Area Electrical Classification – An Area Requiring Some Care, https://www.linkedin.com/pulse/combustible-gas-detection-area-electrical-requiring-some-palluzi

Gas Detection Inside Laboratory Hoods: Prudent Safety Measure or Wasted Money?, https://www.linkedin.com/pulse/gas-detection-inside-laboratory-hoods-prudent-safety-measure-palluzi

Dear Margaret,

As you assess your setup, you may want to begin by reviewing the local and state fire code requirements for storage and any limitations set by the fire and building codes to ensure compliance (max per sq ft, 20 ft from oxidizers, number per room, fire walls, etc.). Your fire marshall should be able to help you. Grounding may also be recommended, but it is important to do so carefully and ensure proper grounding paths. I once encountered a building where numerous items were connected to the ground, rendering it essentially ineffective.

Use only stainless steel or copper for hydrogen handling on installations for compatibility and permeation reasons. They will both experience embrittlement over time, depending on pressure, temperature, and the duration of exposure to hydrogen. From my understanding, whenever modifications are made to the setup, it is advisable to replace the copper and stainless-steel tubing/pipes to mitigate embrittlement concerns and prevent the formation of microfissures during bending or movement. If feasible, flushing the system with an inert gas after use is always recommended.

Regarding material lifespan, a typical replacement period is around 20 years, with periodic inspections throughout the year to ensure continued integrity and safety.

Additionally, having a Lower Explosive Limit (LEL) detector in the room is a key safety measure.

Please feel free to reach out if you’d like to discuss any of these points further. I’d be happy to assist.

Tammy Rechtin, Ph.D.

Chemical Engineering Safety Coordinator

Ralph E. Martin, Department of Chemical Engineering

University of Arkansas

Email: tlutzrec**At_Symbol_Here**uark.edu

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