ASTM D7709 Measuring Water Vapor Transmission Rate (WVTR) of Pharmaceutical Bottles and Blisters

Get Certified ASTM D7709 Testing for Reliable Pharmaceutical Packaging Performance 

Pharmaceutical products are sensitive to moisture, which affects stability, efficacy, and shelf-life. This test method assists manufacturers in gaining insights into packaging resistance to moisture influx under standardized conditions. Certified testing helps select the right packaging materials, design new packaging materials, control the quality of packaging materials, and compare packaging products used in pharmaceutical applications. 

• Material type: Pharmaceutical bottles, blisters, vials, and closures.
• Purpose: The Dry Film Transfer (DFT) Adhesion Test is used to determine WVTR for a moisture barrier. 
• Property measured: Water vapor transmission rate (WVTR) in mass of water vapor per unit time per package. 
• Method: The test involves applying a controlled humidity gradient across the package wall and measuring the amount of water vapor that permeates through. A water vapor transmission rate (WVTR) analyzer is used to track the transmission rate. 
• Result: WVTR is expressed in water vapor mass per unit time per package (e.g., mg/day/package). 
• Test Limitations: The standard provides various test conditions and methods. The user should set up procedures suitable for the type of package and test conditions. 
• Environmental conditions: Tests are performed under controlled temperature and humidity conditions. 
• Applications: Quality control in the pharmaceutical industry, package development, selection of packaging materials, and shelf-life studies. 

What are the Uses of ASTM D7709 Testing?

ASTM D7709 testing helps laboratories assess the moisture barrier performance of pharmaceutical packaging. Engineers then use the results to assess packaging designs and understand the effectiveness of packaging in moisture protection. This standard-

• Measures the moisture barrier performance of the pharmaceutical package.
• Aimed at quality assurance in pharmaceutical packaging production
• Helps in package development and material selection
• Aids in shelf life studies
• Compares packaging materials and designs against each other 

What Materials Can Be Tested Under ASTM D7709? 

ASTM D7709 applies to pharmaceutical bottles, blisters, and vials. Before starting a testing program, an analyst should decide on the package type, test method, and necessary conditions.  Laboratories test high-barrier multiple-unit containers such as bottles,high-barrier single-unit containers such as formed blisters, and quasi-barrier single-unit blister packages. 

Why is ASTM D7709 Important? 

ASTM D7709 specifies a standardized method for assessing how well a closed pharmaceutical container prevents water vapor transport. Moisture-barrier performance is important when manufacturers choose packaging for products that must be protected from environmental humidity. The standard assesses the complete container-closure system, allowing engineers to account for moisture entering the package body, seals, closures, or other components of the assembled package. Reliable WVTR measurements enable manufacturers to distinguish between different barrier packages and make intelligent packaging options throughout development and quality testing. 

ASTM D7709  Testing Process and Data Collection

The analyst selects pharmaceutical packaging samples and determines the test method and conditions. Then, technicians prepare the packaging samples and insert them into the WVTR analyzer. The system controls the packages at the desired temperature and humidity and records the water vapor transmission rate. Technicians calculate the WVTR from the measured data. Analysts record all testing conditions and note any deviations from standard procedures. 

Common Challenges and Troubleshooting

Accurate ASTM D7709 testing needs consistent temperature and relative humidity, reliable package closure, appropriate desiccant preparation, and accurate weighing. Leakage or inadequate closure can increase moisture entry and produce results that do not accurately represent the intended package configuration. Insufficient balancing sensitivity can also have an impact on measurements when packages have very low WVTR values. Technicians double-check balance performance, ambient chamber conditions, package integrity, and weighing processes before and during testing. 

• The lab measures WVTR in milligrams per bottle per day (mg/bottle-day).
• The laboratory provides the WVTR for blisters in mg/cavity-day.
• The analyst determines the package weight gain during the test period and applies the applicable ASTM D7709 calculation procedure.
• The engineer can then compare WVTRs of alternative packages to assess differences in moisture-barrier performance.
• A lower WVTR indicates less water vapor is admitted to the package under the test conditions.
• The report records the tested package configuration and environmental conditions for users to interpret and compare results. 

Link to ASTM D7709