Home >> Products >> Industrial Specialized Testing >> Light Industry >> Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)
Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)

Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)

Model: UT2108A; ISO 15105-1, ISO 2256, ASTM D1434

UT2108A Gas Permeability Tester | Differential Pressure Gas Permeation Analyzer

The UT2108A Gas Permeability Tester, also named differential pressure gas permeation analyzer, is a multi-functional lab instrument dedicated to gas barrier performance testing. Adopting the classic differential pressure testing principle to drive gas penetration, this equipment accurately evaluates barrier resistance of film, sheet and packaging container samples to oxygen (O₂), nitrogen (N₂), carbon dioxide (CO₂) and regular air.

Widely adopted as standard QC testing equipment for flexible packaging, plastic manufacturing and new energy sectors, the tester precisely measures gas transmission rate (GTR) and gas transmission coefficient of plastic films, multi-layer composite films, high-barrier polymer materials, plastic sheets and metal foils under customizable temperature conditions.


Global Standard Compliance

This gas barrier test machine fully meets authoritative differential pressure test standards worldwide:

ISO 15105-1 Plastics - Film and sheeting - Determination of gas-transmission rate - Part 1: Differential-pressure methods

ISO 2556, ASTM D1434, JIS K 7126-1, DIN 53380-1


General introduction

UT2108A Gas Permeability Tester | Differential Pressure Gas Permeation Analyzer

The UT2108A Gas Permeability Tester, also named differential pressure gas permeation analyzer, is a multi-functional lab instrument dedicated to gas barrier performance testing. Adopting the classic differential pressure testing principle to drive gas penetration, this equipment accurately evaluates barrier resistance of film, sheet and packaging container samples to oxygen (O₂), nitrogen (N₂), carbon dioxide (CO₂) and regular air.

Widely adopted as standard QC testing equipment for flexible packaging, plastic manufacturing and new energy sectors, the tester precisely measures gas transmission rate (GTR) and gas transmission coefficient of plastic films, multi-layer composite films, high-barrier polymer materials, plastic sheets and metal foils under customizable temperature conditions.


Global Standard Compliance

This gas barrier test machine fully meets authoritative differential pressure test standards worldwide:

ISO 15105-1 Plastics - Film and sheeting - Determination of gas-transmission rate - Part 1: Differential-pressure methods

ISO 2556

ASTM D1434

JIS K 7126-1

DIN 53380-1


Test Principle:

The instrument uses a differential pressure testing method. The pre-treated sample is placed between the upper and lower test chambers and clamped in place. First, the low-pressure chamber (lower chamber) is vacuumed, and then the entire system is evacuated. Once the required vacuum level is reached, the lower test chamber is closed, and a certain pressure of test gas is introduced into the high-pressure chamber (upper chamber), ensuring a constant pressure difference across the sample (adjustable). The gas then permeates from the high-pressure side to the low-pressure side under the pressure difference. By monitoring the pressure in the low-pressure side, the various barrier properties of the sample being tested can be determined.


Core indicators can be detected: 

Gas Transmission GTR: cm3/m2·24h·0.1MPa (Base Evaluation Indicator)

Gas permeability coefficient, diffusion coefficient, solubility coefficient (for material R&D)

Overall container air permeability: (cm3/(piece·24h); (optional container tooling)

Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)
Pneumatic gripping sampleVacuum pump


Key words: UT2108A gas permeability tester, gas permeation analyzer, differential pressure gas barrier tester, Differential-pressure Method, Gas Transmission Rate Test System, Gas Permeability Test System, Gas Permeability Tester Differential Pressure Gas Permeability Tester, Differential Pressure Air Permeability Tester. gas transmission rate test, gas transmission coefficient measurement, high-barrier film testing, composite packaging barrier performance, oxygen permeation tester, new energy material gas test, metal foil gas barrier inspection. 

Key Features

  • Test principle
  • Main features
  • Overall Structure and Subcomponents
  • Application
  • Standard
  • Complete Test Procedure
  • Differential Pressure VS Coulometric Sensor Method
  • Selection Guide

Chamber Separation: The sample is flattened and sealed between the upper and lower test chambers, completely dividing them into a high-pressure chamber (upstream) and a low-pressure chamber (downstream) without any air leaks.  

Full Vacuum: A two-stage vacuum pump simultaneously evacuates both chambers to below 20 Pa, removing any residual air and eliminating baseline interference.  

Establish Constant Pressure Difference: Close the vacuum valve on the low-pressure chamber, introduce the gas to be tested (O₂/CO₂/N₂) into the high-pressure chamber, stabilize at 0.1 MPa, forming a stable pressure gradient across the sample.  

Permeation Pressure Rise Collection: Under the pressure difference, gas passes through the inter-molecular gaps of the film into the low-pressure chamber, while a high-precision vacuum pressure sensor monitors the pressure rise in real-time.  

Automatic Calculation Output: Using the sample’s effective area, test temperature, pressure difference, and pressure rise rate, the software automatically calculates the steady-state gas permeation and three main permeability coefficients based on the ideal gas law, and plots the pressure vs. time permeation curve.

Gas Permeability Tester - Gas Permeation Analyzer (Differential-pressure Method)


Equipped with a 7-inch touchscreen, displays real-time data and curves (desktop PC option available).  

Supports combined use of the main unit and satellite units (expandable up to 9 units), can be expanded to test up to 30 workstations simultaneously.  

Ultra-high pressure resolution, ultra-low reference zero, minimal zero drift.  

Single unit supports multi-station customization, allowing 1-3 chambers to be tested at the same time.  

Specimen pneumatic quick clamping and release mechanism, supports foot-pedal pneumatic clamping operation.  

Testing range can be customized according to different sample requirements.  

Within the range, pressure is continuously adjustable, fully automatic operation, automatically measures and calculates results.  

Built-in mini printer, can print test reports in real-time.  

Menu-style interface, each test function operates independently through menus, easy parameter setting and test operation.  

Startup password login to prevent unauthorized use, with four-level permission management.  

Computer software supports hierarchical permission management, audit tracking, electronic signatures, etc. (additional purchase required).  

Supports exporting test data in multiple file formats and file verification.

1: Multi-Station Sealed Permeation Chamber Assembly

Main types: single-station and triple independent stations (three-chamber version is more efficient and is the market standard)  

Chamber material: 316 stainless steel, corrosion-resistant, non-deforming, compatible with various test gases  

Pneumatic sealing fixture: cylinder uniformly presses the sample, paired with a vacuum silicone ring seal to prevent edge leaks (leakage is the biggest error source in pressure-difference methods)  

Standard test area: 50cm² (national standard specification); compatible with sample thickness 0.01–3mm including films, hard sheets, aluminum foil  

External/Internal temperature-controlled bath: temperature range 10–60°C, control accuracy ±0.1°C, suitable for high and low-temperature formulation testing  

Independent chamber gas lines: triple station gas lines are completely isolated, can test three different samples simultaneously without interference  


2: Vacuum and Gas Supply System  

Dual-stage vacuum pump set: mechanical pump + molecular pump (for high-end models), quickly reach high vacuum below 20Pa; economic version uses a single mechanical pump  

Multi-channel gas inlet valves: connects oxygen, carbon dioxide, nitrogen cylinders, solenoid valves automatically switch test gases  

Pressure stabilizing and reducing valve: maintains a constant standard test pressure difference of 0.1MPa in high-pressure chambers  

High-precision vacuum pressure sensor: range 0–100kPa, resolution 0.1Pa, accurately captures tiny pressure changes  


3: Drive and Pneumatic Assistance Unit  

0.4–0.6MPa clean dry gas source to drive the chamber clamping cylinder  

Vacuum pipes fully sealed with Teflon, no gas adsorption, ensuring stable micro-permeation testing  

Backflow and oil contamination protection filters, protecting the vacuum pump and sensors.

1. Food packaging industry (biggest application scenario)
Check oxygen permeability for regular PE cling film, PP single-layer bags, composite printed bags, and can packaging films;
Special CO₂ permeability tests for carbonated drink bottles, beer packaging, and modified atmosphere packaging bags (coulometry can't measure CO₂);
Batch inspection for low- and medium-barrier snack and fruit/vegetable packaging materials, cost-effective choice.

2. Plastic film manufacturers
Full inspection for PE, PP, BOPP ordinary packaging films, PVC shrink films, and geosynthetic liners; quickly compare breathability of different extrusion and co-extrusion processes.

3. New energy lithium battery industry
Nitrogen barrier testing for aluminum-plastic composite films, battery separators, and packaging insulation films to assess battery swelling and lifespan; Testing the air permeability of various types of carbon paper for proton exchange membrane fuel cells,  the industry commonly uses differential pressure method to measure N₂ permeability. 

4. Pharmaceutical packaging (routine checks, not high-barrier arbitration)
Ventilation screening for ordinary medical PE bags, topical ointment tubes, and gaskets; arbitration testing for ultra-high-barrier drug plates and sterile bags still needs coulometry or differential pressure methods.

5. Daily chemical, construction, and geotechnical fields
Gas barrier testing for cosmetic tubes, plastic bottle cap gaskets, geosynthetic liners, and PVC door/window sheets.

6. Universities and regular lab R&D
Need to study O₂, CO₂, and N₂ gas permeability simultaneously, limited budget, demand for multi-gas simultaneous testing.

ISO 15105-1 Plastics - Film and sheeting - Determination of gas-transmission rate - Part 1: Differential-pressure methods

ISO 2556 Plastics - Determination of the gas transmission rate of films and thin sheets under atmospheric pressure - Manometric method

ASTM D1434 Standard Test Method for Determining Gas Permeability Characteristics of Plastic Film and Sheeting

GB/T 1038.1 Plastics—Film and sheeting—Determination of gas-transmission rate—Part 1:Differential-pressure methods

JIS K 7126-1 Plastics -- Film and sheeting -- Determination of gas-transmission rate -- Part 1: Differential-pressure method

DIN 53380-1 Testing of plastics - Determination of gas transmissions rate - Part 1: Volumetrical method for testing of plastic films

Sample Pre-treatment: Cut the film into 100×100mm samples without pinholes or wrinkles, and condition them at 23°C/50% RH for 4 hours; accurately record the sample thickness.

Equipment Start-up and Vacuum: Start the vacuum pump and evacuate the high and low-pressure chambers to below 20 Pa, clearing any residual gas in the pipelines.

Clamping and Sealing Samples: Place three samples into the three chamber positions, seal them with pneumatic pressure, enter sample information into the software, and set the test temperature, pressure difference, and test gas.

Establishing the Permeation Pressure Difference: Introduce the test gas into the high-pressure chamber and stabilize it at 0.1 MPa; the system continuously collects pressure data from the low-pressure chamber.

Steady-State Automatic Detection: The software monitors the pressure rise rate, and when it stabilizes, permeation equilibrium is determined, automatically recording the steady-state GTR data.

Data Processing and Reporting: Automatically calculate the average and standard deviation of three parallel samples, generating a test report with the pressure-time curve.

Chamber Depressurization and Cleaning: After the test, the system depressurizes automatically, remove the samples, and purge the chamber for future use.

Core Advantages of Differential Pressure Methods

One machine measures multiple gases: oxygen, nitrogen, carbon dioxide all in one device. Beverage factories can measure O₂/CO₂ simultaneously with just one device, whereas the coulometric method can only measure oxygen alone.

Low procurement and maintenance costs: No expensive consumable electrochemical sensors, only regular maintenance of the vacuum pump is needed, no high-purity nitrogen carrier gas required, and long-term consumable costs are very low.

Strong resistance to water vapor interference: Testing doesn’t rely on strict humidity control. PE, PP single-layer films, and moisture-containing composite films can be tested directly in workshops without easily drifting due to moisture.

Range covers high-permeability materials: Stable testing for high-barrier fresh-keeping films, geotextiles, battery separators. High-permeability samples can be tested quickly.

Can output a complete set of permeability coefficients simultaneously: diffusion, solubility, and permeation coefficients, providing more comprehensive data for material formulation research.


Limitations

Insufficient accuracy for high-barrier materials: Aluminum foil, EVOH, PVDC ultra-low permeability films (<0.5 cm³/(m²·24h)) have large errors. According to national standards, high-barrier oxygen arbitration still prefers the coulometric method.

Long testing cycles: Full vacuum, slow pressurization, and equilibrium stages result in 4–8 hours for normal films and up to 24 hours for high-barrier films; the coulometric method only takes 0.5–3 hours.

Cumbersome vacuum system maintenance: Vacuum pump oil needs periodic replacement, and any pipeline leaks can directly ruin the data.

No native humidity control module: Standard models can’t accurately control humidity. Hydrophilic films like nylon or EVOH require additional temperature and humidity chambers for wet-state testing.

1, Choose Differential Pressure Gas Permeability Tester:  

Needed when testing multiple gases like O₂, CO₂, and N₂ at the same time;  

For testing materials like PE/PP single-layer films, battery separators, carbonated packaging, geotextiles, and other highly breathable materials;  

Suitable for large-scale daily inspections in workshops, with budget constraints, and aiming for low maintenance costs;  

Special testing in the lithium battery and carbonated beverage industries.  


2, Choose Coulometric Isobaric Oxygen Permeability Tester:  

For ultra-barrier films like aluminum foil, EVOH, PVDC, pharmaceutical sterile packaging, and export arbitration testing;  

Only tests oxygen, aimed at high precision, short test cycles, and precise controllable temperature and humidity.

Main Technical Specification

Test range0.01~50,000 cm³/m²·24h·0.1MPa (standard)
Upper limitnot less than 600,000 cm³/m²·24h·0.1MPa (extended volume)
Number of samples1 or 3 stations  (data independent)
Vacuum resolution0.05 Pa
Test chamber vacuum<10 Pa
Temperature control range5~95°C
Temperature control accuracy±0.1°C
Sample size50*50mm
Permeable area16 cm²
Test gasesO2, N2, CO2, etc. (user provides gas source)
Test pressure0.1 MPa~0.26 MPa
Interface sizeФ6 mm polyurethane tube
Dimensions650 mm (L) × 550 mm (W) × 500 mm (H)
Power supplyAC 220V 50Hz
Net weight55 kg


Main Accessories

Standard Configuration: Main unit, water bath device, professional software, communication cable, mini printer, dedicated sampler, vacuum grease, quick quantitative filter paper, vacuum pump, computer

Optional Accessories: Standard membrane, vacuum pump oil, humidity generator

Note: The machine's air inlet uses a 6mm polyurethane tube; the air source must be provided by the user.

Standard

ISO 13636 Non-oriented PET Films sheeting test requirement (APET)

ISO 13636 specifies requirements anf test methods for non-oriented PET (APET) sheets — made from virgin, recycled, or combined PET, thickness < 2.0 mm. It explicitly excludes foamed sheets and shrinkable films (those are covered elsewhere, e.g. biaxially oriented PET in ISO 15988). The mandatory performance tests including Tensile stress at yield, Heat shrinkage, Oxygen transmission rate (OTR), haze value, Intrinsic viscosity (IV).

ISO 15988 Biaxial stretch PET films test methods details

ISO 15988 specifies requirements for biaxially oriented transparent PET (BOPET) films, mainly used for packaging, either alone or as a laminated layer with other films. The main test stipualted in this standard include tensile strength and strain, Dimensional change on heating, Oxygen transmission coefficient, Water vapour transmission coefficient, Haze, Wetting tension, thickness etc., 

ISO 15987 Biaxially oriented nylon films tensile expansion testing methods

ISO 15987 specifies classification, mandatory visual, dimensional, mechanical, barrier, optical, surface energy, and food contact safety requirements for transparent BOPA film, supplied in roll form, either used standalone or laminated with PE, CPP, PET, aluminium foil for multi-layer packaging structures. The test stipulated in ISO 15987 mainly include, tensile strength & tensile strain at break, Oxygen transmission coefficient, Dimensional change on heating, Haze, Wetting tension etc., 

ISO 17555 BOPP films biaxial stretch testing methods

ISO 17555 applies to packaging-grade BOPP films containing ≥95% polypropylene resin; usable as single-layer film or laminates paired with other plastic substrates. The test stipulated in ISO 17555 mainly include, tensile strength & strain at break, Dimensional change on heating (thermal shrinkage), Coefficient of water vapour transmission, Haze, Wetting tension etc., 

Require More Customized Solutions?

We offer customization to meet your specific needs. Our expert team will collaborate with you to develop the perfect product for you
Customize Now

Beijing United Test Co., Ltd.