Oxygen transmission rate and water vapour transmission rate are two key material specification properties which determine the shelf life of food packaging.
Smithers Pira offers a full range of barrier testing services, including an inter-laboratory proficiency scheme.
Laboratory Permeability Testing
The oxygen transmission rate (OTR) of films and packs is determined using benchmark MOCON OX-TRAN 2/21 equipment.
The water vapour transmission rate (WVTR) of films and packs is tested using the MOCON PERMATRAN-W 3/33.
Carbon dioxide, nitrogen, methane and other gas permeability through films can be measured using Lyssy L100-5000 equipment.
"Real-Life" Permeability Testing
Smithers Pira is also able to evaluate the oxygen permeation of packs under “real-life” conditions using the Mocon OpTechTM platinum analyser with a flourescence-based sensor.
The sensor can be mounted within the pack for non-destructive permeation analysis in accordance with ASTM F2714.
Used in conjunction with a test cell, the apparatus is capable of accurately measuring the transmission rate of oxygen through micro-perforated films using the Dynamic Accumulation method described in ASTM F3136. Because this method does not require a constant flow of carrier gas, it is ideal for measuring the oxygen transmission rate of perforated packaging used in the food industry.
Smithers Pira also offer a pre-test integrity assessment on packs using a high sensitivity gas leak detection system and pre-conditioning of films by controlled flexing to ASTM F392 using a standard Gelbo flextester.
Standards and Accreditation
- Oxygen permeability testing is made in accordance with ASTM D-3985, ASTM F-1927 and ASTM F-1307, DIN 53380-3 or JIS K 7126.
- Water vapour permeability rates can be determined according to ASTM F1249, BS 7406 method A, ISO 9932 or TAPPI T557.
- Other gas transmission rates are determined against the test methods detailed in ASTM D1434 and DIN 53380-1.
- Other standards for WVTR based on pack or dish methods include USP <671>, ASTM E96, BS 2782:820A, BS 3177, DIN 53122 and JIS Z 0208, are also available.
Smithers Pira is ISO 17025, UKAS accredited for oxygen transmission rate testing to ASTM D-3985, ASTM F-1927 and ASTM F-1307, and moisture vapour transmission rate testing to ASTM F-1249 and BS 3177.