Altitude and Low Pressure Testing
Accredited low pressure testing from sea level to 15,000 m. We hold your product at altitude, powered or unpowered, and record exactly what changes.
- Prove it works where it ships: Validate operation and survival at cabin, cargo hold and high-site altitudes before a customer finds out for you.
- Catch all three failure modes: Convection cooling stops, sealed enclosures push outward, and anything with an internal air gap drifts out of spec.
- Accredited to IEC 60068-2-13: on our ISO 17025 accredited scope, sea level to 15,000 m.
Accredited environmental testing
ISO/IEC 17025
A2LA #5179.01
Controlled Goods Program
CGP registered
*Send us the altitude, the dwell time and whether the unit is powered. Detailed quote and schedule, typically within one business day.
Trusted by industry leaders
What altitude testing proves
Altitude testing, also called low pressure testing, puts your product in a sealed chamber and lowers the pressure around it to match a given height above sea level. We hold it there, or walk it through a pressure profile, and record how it behaves. IEC 60068-2-13 is the method, and our accredited range runs from sea level to 15,000 m.
The point is that a product validated on a bench in Toronto has only ever been tested at about 150 m. Cruise altitude in an unpressurised cargo hold is closer to 2,400 m of cabin pressure, a decompression event is far higher, and a mine site in the Andes sits above 4,000 m all day long. Nothing about the bench result predicts any of that.
The three things low pressure changes
Cooling quietly stops working
Thin air carries less heat away. A part that ran comfortably at sea level can sit tens of degrees hotter at altitude with nothing else changed, because convection has largely stopped. Fan-cooled designs lose twice, since the fan is also moving thinner air.
Sealed things push outward
Any enclosure, pouch, bag or filled container is now holding a pressure difference across its own seams. This is what splits pouches, pops lids, forces gaskets out of their grooves and makes sealed electronics leak on the way back down rather than on the way up.
Air-gap components change character
Anything that depends on air inside it behaves like a different part. Fans move less mass, electrolytic capacitors bulge, arcing and creepage margins shrink as the dielectric strength of air falls, and pressure sensors read against a reference that has moved.
Who books altitude testing
- Avionics and cabin equipment. Anything flying has to work at cruise altitude and survive the cabin losing pressure.
- Equipment headed somewhere high. Mine sites, telecom towers and observatories above 3,000 m, where the hardware was designed and signed off a few hundred metres above the sea.
- Anything shipped by air. A sealed device or a filled container leaves at sea level, spends hours in an unpressurised hold and arrives split, leaking or open.
- Lithium cells and battery packs. UN 38.3 Test T.1 is an altitude test, and no cell ships by any mode without it.
How we run it at Megalab
Testing follows IEC 60068-2-13. You tell us the altitude or the absolute pressure you need, how long to hold it, whether the unit is operating during the test, and what counts as a failure. We tell you what will fit, how long the chamber time runs, and what the report will say. Results come back as an ISO 17025 accredited report you can put in front of a customer or a regulator.
What to send us
- The altitude or pressure, the dwell time, and the rate of change if your spec gives one
- Whether the unit runs during the test, and how we power and monitor it
- Overall dimensions, weight, and any cable that has to leave the chamber
- Two samples where you can spare them. One is enough to screen a design, but a second saves a full re-book when the first one fails and you need to know whether it was the design or the sample.
Altitude testing standards we run
Most altitude work arrives as a low pressure clause inside a larger qualification programme. We run altitude and low pressure testing to IEC 60068-2-13, MIL-STD-810 Method 500, RTCA DO-160 Section 4, the IEC 60601 reduced pressure limits and UN 38.3 Test T.1, all in the same altitude test chambers with the same instrumentation and reporting.
MIL-STD-810 Method 500 altitude testing
MIL-STD-810 Method 500, Low Pressure (Altitude), is the method defence and aerospace programmes call out for equipment that is stored, operated or carried at altitude, in both MIL-STD-810G and MIL-STD-810H test plans. The procedures most test plans name are:
- Procedure I, storage and air transport: the equipment is held unpowered at altitude, then inspected and function checked once it is back at ambient pressure.
- Procedure II, operation and air carriage: the equipment runs at altitude, where thin air cuts cooling and changes how seals and air gaps behave.
- Procedure III, rapid decompression: a fast drop from cabin pressure to flight altitude, representing a loss of cabin pressure.
Method 500 usually sits in the same test plan as the temperature, humidity and vibration methods, and we run those alongside it. See MIL-STD-810 testing.
RTCA DO-160 Section 4 altitude testing
RTCA DO-160 Section 4, Temperature and Altitude, sets the conditions for airborne equipment by where it is installed in the aircraft and how high that aircraft flies. The equipment category decides the test levels, so the first step on any DO-160 altitude test is confirming the category your specification calls for.
- Altitude: operation at the maximum operating altitude for the equipment category.
- Decompression: a loss of cabin pressure, for equipment installed in pressurized areas.
- Overpressure: pressure above normal cabin levels, for equipment installed in pressurized areas.
Section 4 is usually booked with the Section 5 temperature variation and Section 6 humidity tests. See DO-160 testing.
Medical device and battery altitude requirements
- IEC 60601-1-11 and 60601-1-12 (medical electrical): the reduced pressure limits for home healthcare and for emergency and air transport equipment.
- UN 38.3 Test T.1 (lithium batteries): altitude simulation for cells and packs, covered below.
Send us the standard and clause on your specification, and we will confirm the method, the profile and the schedule before you book.
Lithium batteries: UN 38.3 Test T.1
Shipping a lithium cell or battery by air, sea or road means passing UN 38.3, and the first of its eight tests is altitude simulation: 11.6 kPa or below for at least six hours at ambient temperature. It passes on no leak, no vent, no disassembly, no rupture and no fire, with at least 90 percent of the pre-test open circuit voltage still there at the end. We are accredited for UN 38.3 and for altitude, so if a battery is what brought you here, ask about the full T.1 to T.8 sequence rather than booking the altitude leg on its own.
Test it and simulate it in the same place
Low pressure problems are usually thermal problems, and a thermal model tells you where to put the thermocouples before the chamber door closes. Our MEGASIM engineering simulation team runs the CFD and thermal analysis, the chamber produces the measured result, and the measured result calibrates the model. After that, the next design change can be judged without booking chamber time again.