Helium Allocation Alternatives: Switch to Hydrogen Forming Gas for Leak Detection
On helium allocation, paying surcharges, or unable to open a new helium account? Forming gas, a non-flammable blend of 5% hydrogen and 95% nitrogen, replaces helium as a tracer gas for most HVAC and refrigeration leak testing. It costs less, it is easy to get, and it is not subject to helium allocations.
Talk to a Leak Detection Specialist See Hydrogen Leak DetectorsThe 2026 Helium Shortage: Allocations, Surcharges and Force Majeure
In March 2026, attacks on Qatar's Ras Laffan complex took roughly one-third of the world's helium supply offline. Industry observers expect the repairs to take years, not months. Major U.S. gas suppliers responded by declaring force majeure, rationing customers to a fraction of their historical volumes, and adding per-cylinder surcharges on top of contract pricing. Some suppliers are not accepting new helium customers at all.
When helium is scarce, suppliers send what they have to healthcare and life-critical users first. Service contractors and manufacturers who use helium only for leak detection end up at the back of the line. For these users, the most practical alternative to a helium allocation is to stop needing helium for leak testing.
What Is Forming Gas, and Why Is It the Leading Helium Alternative?
Forming gas is a standard industrial mixture of 5% hydrogen (H2) and 95% nitrogen (N2). Welders already use it as a shielding gas, so most welding and industrial gas distributors keep it in stock. Hydrogen is the lightest molecule there is, which makes it an excellent tracer gas. A hydrogen leak detector senses the hydrogen in the mix at very low concentrations.
Five reasons forming gas beats helium during an allocation
- It has its own supply chain. Forming gas contains no helium. Hydrogen and nitrogen are produced at large scale through processes that have nothing to do with helium production, so helium allocations, force majeure notices and helium surcharges do not apply.
- It costs less. The cylinder is 95% nitrogen, one of the cheapest industrial gases, so forming gas costs far less than helium and its price stays more stable.
- It is non-flammable. Under ISO 10156, hydrogen-nitrogen mixtures with less than 5.7% hydrogen are classified as non-flammable. Standard 95/5 forming gas needs only normal compressed-gas handling.
- It works faster and clears easier. Hydrogen has low viscosity and spreads quickly through a pressurized system and out through small leaks. Helium tends to cling to surfaces and linger in the work area. Hydrogen vents away quickly, so readings from background gas drop off and you can move on to the next joint sooner.
- The detectors cost less. Handheld hydrogen leak detectors use solid-state sensors that are highly selective for hydrogen. They cost a fraction of what a helium mass-spectrometer leak detector costs.
Helium vs. Forming Gas: Side-by-Side Comparison
| Factor | Helium | Forming Gas (5% H2 / 95% N2) |
|---|---|---|
| Subject to helium allocation | Yes, often 40–50% of prior usage in 2026 | No |
| Supplier surcharges | Common during shortages | Not tied to the helium market |
| Availability | Limited; some suppliers refuse new accounts | Stocked by most welding and industrial gas suppliers |
| Cost per test | High and rising | Low |
| Flammability | Inert | Non-flammable per ISO 10156 (<5.7% H2) |
| Clearing from work area | Lingers and clings to surfaces | Disperses quickly |
| Detector cost | Mass spectrometer: high | Handheld hydrogen sniffer: low |
| Background level in normal air | About 5 ppm | About 0.5 ppm hydrogen, roughly 10× lower |
| Best suited for | Hard vacuum testing of leaks finer than ~1E-5 atm cc/sec | Sniffer testing down to ~1E-5 atm cc/sec: HVAC, refrigeration, production sniffing |
Helium Alternatives by Application
HVAC service
Most HVAC technicians already carry nitrogen for pressure testing. To switch, pressurize the system with forming gas instead of straight nitrogen, then sniff brazed joints, flare fittings, coils and service valves with a hydrogen leak detector. You use the same regulator and the same procedure, and you get far better pinpointing than a pressure-drop test alone gives you.
Refrigeration system service
Large refrigeration systems have long piping runs, evaporator coils and multiple circuits. Hydrogen spreads through all of them quickly. Forming gas lets technicians find leaks in systems that have lost their charge, without buying expensive helium or adding more refrigerant. The H2Leak DXR-240 detects both hydrogen and refrigerants, so one instrument covers charged and uncharged systems.
When Is Helium Still Required?
Sniffing has a practical limit, whichever tracer gas you use. Normal air contains about 5 ppm helium and about 0.5 ppm hydrogen. That natural background limits how small a leak any sniffer can pick out, so a handheld helium or hydrogen sniffer generally cannot reliably find leaks below about 1×10-5 atm cc/sec in field conditions. High-end production sniffers with background compensation can go somewhat lower in controlled settings. Down to that level, forming gas has the advantage, because the air carries roughly ten times less hydrogen than helium.
For finer leaks, change the method, not the gas. When a specification calls for leak rates below 1×10-5 atm cc/sec, hard vacuum testing is the right approach. Hard vacuum testing still requires helium, but you can use a diluted helium/nitrogen mix to reduce consumption. Helium reclaim systems are another option, although they are expensive.
Ultra-fine specifications like these mostly apply to factory testing. HVAC and refrigeration leak checks are sniffer applications, and forming gas handles them well.
How to Switch from Helium to Forming Gas
- Review your leak-rate requirement. If your specification is about 1E-5 atm cc/sec or larger, which covers field service work and most production sniffing, forming gas is a practical replacement. Finer specifications call for hard vacuum testing, whichever tracer gas you use.
- Order 95/5 forming gas from your local welding or industrial gas supplier. It uses standard cylinders and regulators.
- Choose a hydrogen leak detector. The H2Leak DXH-240 is a dedicated hydrogen detector. The H2Leak DXR-240 detects both hydrogen and refrigerants.
- Pressurize and sniff. Charge the system with forming gas to your normal test pressure, then sweep the probe slowly along joints and components.
- Vent and finish. Hydrogen disperses quickly, so cleanup is fast and the next job starts with a clean background.
Helium Allocation Alternatives: Frequently Asked Questions
What is the best alternative to helium for leak testing during a helium allocation?
Forming gas, a mixture of 5% hydrogen and 95% nitrogen, is the most widely used helium alternative for tracer gas leak detection. It is plentiful, inexpensive, non-flammable, and detected with a hydrogen leak detector.
Is 5% hydrogen / 95% nitrogen forming gas flammable?
No. Under ISO 10156, hydrogen-nitrogen mixtures with less than 5.7% hydrogen are classified as non-flammable.
Is forming gas subject to helium allocations?
No. Forming gas contains no helium, and hydrogen and nitrogen are produced through entirely separate supply chains.
Can forming gas be used for HVAC and refrigeration leak detection?
Yes. Pressurize the system with forming gas and sniff joints, brazes and coils with a hydrogen leak detector such as the H2Leak DXH-240 or the dual hydrogen and refrigerant H2Leak DXR-240.
When is helium still required?
Helium is still required for hard vacuum testing, the method used for leaks finer than about 1E-5 atm cc/sec. Below that level, neither helium nor hydrogen sniffing works reliably, because both gases are present in normal air. Hard vacuum testing can use diluted helium to reduce consumption, and helium reclaim systems are another, more expensive option.
How long will the helium shortage last?
Industry sources project tight helium supply for up to five years following the 2026 Ras Laffan damage, with elevated prices for up to three years.
Stop Depending on Helium for Leak Detection
H2Leak has supplied hydrogen tracer gas leak detectors since 2007, serving HVAC and refrigeration service professionals. If you are dealing with helium allocations or rising helium prices, we can help you move to forming gas.
Contact H2Leak Shop DXH-240 & DXR-240Last updated October 2026. Helium market conditions change quickly; check with your gas supplier for current allocation status.
