Content owner: Packaging Factory Direct. Published and reviewed: . Final material suitability and shelf life must be validated using the buyer's filled product and intended market conditions.
Define OTR and WVTR before comparing films
Oxygen transmission rate (OTR) describes oxygen passing through a material under stated test conditions. Water vapor transmission rate (WVTR) describes water vapor passing through a material under stated conditions. Both are properties measured by a defined method; neither is a universal score that can be copied from one application to another.
ASTM F1249-25 covers a method for determining WVTR through flexible barrier materials and applies to sheets and films up to 3 mm (0.1 in.) in thickness. ASTM states that purchaser and seller should agree on sampling, standardization, test conditions and acceptance criteria when using the data as a referee method. ASTM D3985 addresses oxygen transmission through plastic film and sheeting using a coulometric sensor.
Barrier RFQ decision table
| Question | Buyer input | Why it changes the specification | Evidence to request |
|---|---|---|---|
| What is being packed? | Product composition, oil or moisture sensitivity, aroma and oxidation risks | Different deterioration mechanisms need different controls | Product-owner shelf-life basis |
| How is it filled? | Temperature, speed, equipment, product contamination at the seal area | The sealant layer and pouch geometry must work on the filling line | Trial result or agreed machine conditions |
| Where is it stored? | Temperature, relative humidity, light and expected storage period | Barrier measurements and real package behavior depend on conditions | Test report with conditions and units |
| How is it distributed? | Carton packing, altitude, parcel or freight route and handling risks | Flex cracking, abrasion and seal loads can affect the complete pouch | Packed-product distribution test plan |
| How is it opened and reclosed? | Zipper, spout, valve, tear notch or one-time opening | Closures and converted features can become the package's limiting point | Closure drawing and functional acceptance criteria |
Do not specify a laminate name without a performance context
Material names such as PET/PE, MOPP/VMPET/PE, paper laminate or mono-material PE describe a construction direction, not guaranteed shelf life. Gauge, resin, coating, metallization, adhesive, print, conversion and manufacturing variation can change performance. A material that is appropriate for a dry snack may not be appropriate for an oxygen-sensitive powder or a hot-filled liquid.
Use a two-level specification:
- Construction requirements: layer family, nominal thickness or mass, sealing layer, print method, closure and pouch dimensions.
- Performance requirements: agreed OTR or WVTR method and conditions, seal-strength or integrity criteria, dimensional tolerance and filled-package validation owned by the buyer.
If sustainability is a project goal, define it separately. A mono-material direction does not prove recyclability in every market, and a barrier claim does not prove compatibility with a local collection stream. Ask for current, project-specific evidence rather than relying on a generic recycling logo.
Match the seal system to the filling process
Many pouch failures occur at the seal, zipper, spout or fold rather than through the undamaged center of the film. Provide the filling-line details before sampling:
- Manual, semi-automatic or automatic filling.
- Product temperature at filling and sealing.
- Expected product contamination in the seal area.
- Seal-jaw type, available temperature range, dwell time and pressure controls.
- Required zipper, valve, spout, cap, tear notch or hang hole.
- Filled weight, headspace and expected drop or compression risk.
Do not treat a supplier's seal-temperature suggestion as a validated production window. Establish the operating window on the intended equipment with representative material and product.
Food-contact statements must be project specific
The U.S. Food and Drug Administration explains that substances used in food-contact materials can require authorization based on their intended use. For a food pouch RFQ, identify the food type, direct or indirect contact, temperature, duration and destination market. Request documents for the exact material structure and supply chain selected for the order.
A website statement such as "food grade" is not enough to establish suitability. The buyer should review the applicable authorization, declaration, migration or supplier documentation with a qualified regulatory professional. Packaging Factory Direct does not claim FDA approval or a food-contact certification merely because an official source is cited here.
Quote-ready high-barrier pouch checklist
- Product name and relevant sensitivity to oxygen, water vapor, light, aroma or oil.
- Target shelf life and the evidence used to set it.
- Filling temperature, equipment and seal-area conditions.
- Storage temperature and humidity plus distribution route.
- Pouch style, finished dimensions, gusset, filled weight and headspace.
- Zipper, valve, spout, cap, notch, hole and opening requirements.
- OTR/WVTR method, units, conditions, sampling and acceptance criteria where required.
- Print colors, artwork, surface finish, quantity and destination country.
- Food-contact or other market documents required for the exact application.
- Filled-package test and approval responsibility.
Related flexible packaging pages
- Custom stand up pouches
- MOPP/VMPET/PE flexible packaging guide
- Mono-material high-barrier stand up pouch
- Recyclable mono-material pouch for snacks and nuts
- Packaging quality control process
Primary sources and limitations
- ASTM F1249-25: Water Vapor Transmission Rate Through Plastic Film and Sheeting
- ASTM D3985: Oxygen Gas Transmission Rate Through Plastic Film and Sheeting
- FDA: Packaging and Food Contact Substances
ASTM test-method references and FDA information are buyer-side specification resources. They are not certifications held by this website and do not replace filled-product shelf-life, seal or regulatory validation.
FAQ for flexible pouch buyers
What is OTR in flexible packaging?
OTR is oxygen transmission rate, a measured rate of oxygen passing through a material under stated test conditions. The value is only meaningful when the test method, temperature, humidity, specimen configuration and units are identified.
What is WVTR in flexible packaging?
WVTR is water vapor transmission rate, a measured rate of water vapor passing through a material under stated conditions. ASTM F1249 covers a method for flexible barrier materials and shows why method and conditions belong beside the reported value.
Can buyers compare barrier numbers from different suppliers directly?
Only when the method, units, temperature, relative humidity, specimen structure and other test conditions are comparable. A lower number from a different condition is not automatically a better package.
Does a high-barrier film guarantee product shelf life?
No. Shelf life also depends on the product, initial quality, headspace, filling process, seals, closures, storage, light, distribution and package integrity. The product owner should validate the complete filled package.
What should be sent for a high-barrier pouch quotation?
Send the product and fill conditions, target shelf life, storage and distribution environment, pouch size, filling equipment, seal method, closure, quantity, print design, destination market, required test methods and acceptance criteria.
Request a flexible pouch quotation
Send the product, fill conditions, pouch dimensions, closure, quantity, artwork, destination and any agreed barrier test requirements.
Send RFQ Details