Testing Bags and Pouches
The Sterilization Packaging Manufacturers Council sets standards to educate and increase awareness.
Sidebar: SPMC to ASTM
In the precise world of medical packaging, clarification is a never-ending process. And the Sterilization Packaging Manufacturers Council (SPMC; Linthicum, MD) considers that an important part of its mission.
ï¿½One thing that has been paramount for SPMC, and especially for the technical committee, is to educate and increase the awareness in the industry,ï¿½ says Marie Tkacik, engineering manager for Tolas Healthcare Packaging (Feasterville, PA) and chair of the SPMC Technical Committee. The organization, a subset of the Flexible Packaging Association, works to lift the veil of mystery that surrounds some test methods and to make them less confusing.
This is true even for some of the industryï¿½s oldest methods. SPMC has worked for much of the past year on an updated round-robin for ASTM F88 Standard Test Method for Seal Strength of Flexible Barrier Materials. ï¿½When we originally got together [in 1994], one of the things that we all agreed had the biggest impact was seal strength,ï¿½ says Tkacik. The committee decided that it wanted to provide the industry with more information about the methodï¿½s use. ï¿½We worked with Hut Theller of Theller Engineering, the ASTM task group leader who modernized the document and added the changes we requested, along with the categorizations of seal failure types.ï¿½
In the round-robin process, SPMC is creating test samples and sending them out to 12ï¿½14 participating labs. The labs will run the actual tests, then send the data back to SPMC for analysis. The result will be a ï¿½precision and biasï¿½ statement that will become part of the F88 standard. ï¿½The purpose of the round-robin is to determine how much variability there is in the test,ï¿½ says technical committee member Dhuanne Dodrill of Rollprint Packaging (Addison, IL). ï¿½As a group, the converters are largely performing tests the same way. But there are a lot of tricks to improving accuracy.ï¿½
SPMC has incorporated several techniques into the method to help in this regard, explains Tkacik. ï¿½One particular aspect of running a peel test deals with what is called the ï¿½tail angle of peel.ï¿½ Holding this ï¿½tailï¿½ in a certain position, at 90ï¿½ or 180ï¿½, for example, can cause the results to be substantially different,ï¿½ she says. ï¿½We created drawings to address three different techniques. The round-robin incorporates these differences and will be an aid in understanding the effect of each on the results.ï¿½
The round-robin will make clear which differences in testing technique affect results, according to Jackie Daly Johnson, technical committee member and president of Beacon Converters (Saddle Brook, NJ). ï¿½Itï¿½s testing many different variations of doing the test,ï¿½ says Johnson. ï¿½It will illuminate what differences in test results may be a result of nuances in the way these tests are performed.ï¿½ Results will also make clear how much variation there would be when the test is performed in exactly the same way.
The round-robin has implications beyond the medical packaging industry, and has attracted the participation of companies from the food and photo industries, as well as others. ï¿½Of course, consistent and uniform seals are most critical for the sterile medical device industry, as good seals are required to maintain the sterile barrier,ï¿½ says Bob Dodrill, president of Rollprint, and chair of SPMC Executive Committee.
Work on the F88 round-robin should be finished by April this year.
Jeff Murak, director of sales and marketing for Oliver Products (Grand Rapids, MI), calls the SPMC work on the standard ï¿½another step in the right direction regarding standardization and the elimination of confusion.ï¿½
Other current projects
Recently, the committee also completed the round-robin for ASTM F2203 Standard Test Method for Linear Measurement Using a Precision Steel Rule. Dhuanne Dodrill says that while companies had their own test methods for this, there was no industry standard. The round-robin helped make clear the margin of error that was possibleï¿½an amount that can exceed the very tight tolerances that many medical device manufacturers desire, he explains.
SPMC often works with ASTM to develop standards, and it has proven to be a valuable resource, says Hal Miller, director of packaging technology at Johnson & Johnson, a member of ASTM F02 Committee on Flexible Barrier Materials, and past chairman of F02.60 Subcommittee on Medical Device Packaging. ï¿½They have been a group that has brought a lot of standards proposals to ASTM,ï¿½ Miller explains. ï¿½Theyï¿½ve been a catalyst to move the standards along and have come up with a lot of new ideas for standards.ï¿½
As a task group leader, Miller is currently working on an ASTM guidance document for writing pouch specifications. ï¿½SPMC group is a wealth of knowledge in this area, so I used it as my task group,ï¿½ says Miller. He is now incorporating the groupï¿½s feedback into his draft of the guidance document, which will likely go to ASTM for a subcommittee ballot in the fall.
Questions for the future
John Richard, North American business manager for DuPont Medical Packaging (Wilmington, DE), hopes that SPMC will address ï¿½adoption of a test method that quantifies the microbial barrier resistance of porous packaging materials, such as the proposed standard, ï¿½Standard Test Method for Determining the Microbial Barrier of Porous Packaging Materials Using the Aerosol Filtration Method,ï¿½ currently circulating in ASTM subcommittee F02.06.ï¿½
The existing test method, F1608, ï¿½Standard Test Method for Microbial Ranking of Porous Packaging Materials,ï¿½ is both a time-consuming and expensive test method since it requires the use of live microbes to challenge the packaging material, Richard explains. The proposed additional method being circulated by the Barrier Test Consortium uses physical particles in place of live microbes to challenge the material. It is anticipated that this will be an easier, cheaper, and quicker means to measure a materialï¿½s microbial barrier resistance.
Richard would also like to see SPMC consider reviewing the various test methods used to evaluate printing and its applicability in medical device packaging. Most of the existing standards used in the medical industry only address ink adhesion issues, says Richard. But, as the use of variable data on medical packaging increases, bar coding labeling and the evaluation of bar code label print quality to medical industry standards will become more important, he says.
On the Web
Tkacik says that in the immediate future, the technical committee will focus on expanding the FAQ section of the SPMC Web site (www.sterilizationpackaging.org). The site currently offers a forum where those in the industry can submit questions to be answered by the technical committee. The questions and answers are posted on the site.
The FAQ is important because there are many new companies that donï¿½t have much experience with packaging, according to Beacon vice president of marketing Kathleen Daly Mascolo. ï¿½I think that a lot of the start-up medical device companies donï¿½t necessarily have packaging engineers on staff,ï¿½ says Mascolo. Rather than asking a single supplier for information, they can submit questions to SPMC and get an unbiased answer.
One unique thing about the FAQ section, says Johnson, is that the answers posted there represent an industry consensus. ï¿½As a group we represent the manufacturers who make most of the medical packaging in the world,ï¿½ she explains. Current topics in the section include guidelines for writing a pouch specification and the effect that pinholes in the foil layer may have on the barrier properties of a multiple-layer lamination. Future questions will touch on the F88 round-robin. ï¿½Itï¿½s important to discuss these round-robin results in a little more detail,ï¿½ says Johnson.