ASTM F1608 Standard Test Method for

Microbial Ranking of Porous Packaging

Materials ( Exposure Chamber Method).

Agenda

• Basic overview of the test method

• Proposed changes for the future.

Microbial Ranking Test - ASTM F1608

Copyright Nelson Laboratories 2014 3

Determines the Log Reduction Value (LRV) of porous material

Sample size must be a minimum of 47mm

in width

Packages placed into a chamber and

exposed to a specific organism (Bacillus)

Filters are blended and plated to

determine titer values

How it works..

Microbial Ranking Test

Copyright Nelson Laboratories 2012 9

Supplies • 55 Soybean Casein Digest Agar Plates • 500 mL Soybean Casein Digest Broth • 1000 mL Sterile Water • 7 (0.45 um) Nitrocellulose filters • Plating equipment

3 key proposed changes

1) Equipment availability

2) Chamber evacuation process.

3) Titration methods

1) Standard equipment issue…

• DeVilbiss #40 Nebulizer no longer available.

2) Exposure chamber evacuation “After exposure, turn off the vacuum, and the fan. Evacuate the chamber for 15 min by connecting the vacuum source to the chamber through a microbial filter assembly”

3) Titration methods

Tyvek 0.6 Weight Meltblown

Reference Material 0.45µm Pre-sterilized

Filters

Extraction Method Blended Vortex (10-1

Only) Vortex including

Direct Plating Blended Vortex Blended Vortex

Standard Deviation 0.8 0.6 0.6 0.2 0.2 0.2 0.1

Reproducibility 2.2 1.8 1.6 0.7 0.6 0.5 0.4

Thank you