Tried and True, Bold and New
New testing methods challenge medical device packagers as well as the makers of competing techniques.
|The PTI-225 from Packaging Technologies & Inspection has a manual test chamber for Tyvek.|
Package-testing tools range from something everyone has--the human eye--to new, high-tech equipment that can see inside a package seal or detect microscopic defects in materials. As ASTM works to approve standards for many emerging technologies, companies offering long-established testing methods are employing heightened customer service and product refinements to stay competitive.
Keeping Their Edge
Van der Stahl Scientific (Wrightwood, CA) has a patent pending on a technology that takes the granddaddy of package-testing methods, visual inspection, to a new level. Van der Stahl's viu visual inspection unit uses polychromatic side light to illuminate the sealed area of a package. It provides magnification to allow better visual inspection of the seal. The idea is to provide a "repeatable, consistent standard" for visual seal inspection, says president Charlie Webb.
Van der Stahl also applies the most widely used standard, ASTM-F88, in concert with computer software that gathers data 20 times per second and creates an x-y graph of a seal's performance, says Webb. "It gives a very good picture of how strong that seal is."
The company is currently working on a package tester that is integrated into tabletop sealing equipment and prevents the operator from continuing production if a package fails a test. Van der Stahl hopes to have this technology on the market in mid-2004.
T.M. Electronics Inc. (TME; Boylston, MA), maker of burst, creep, and creep-to-failure testing equipment, has introduced more-sensitive leak testing equipment. "The TME Solution leak tester has the capability to test for pressure changes to 0.0001 psi, which can find micron to sub-micron-size holes in products," says executive vice president Stephen Franks.
To keep customers aware of their options, TME has several educational booklets available on its Web site at www.tmelectronics.com. "Education in the use of existing testing procedures and products is key to keeping customers aware of the benefits of current test technologies," says Franks.
Test-a-Pack Systems, Carlton Technologies (Orchard Park, NY), often develops test equipment around customer requests. Most recently, the firm developed a new product called the F100-2800 series package testing system. "It is a seal-strength tester that also has capabilities to do mass flow and pressure decay with an open-package test fixture. It was needed in the converting field for open-ended packages being produced for medical, food, and pharmaceutical companies," says sales manager Jim Zynda. "We also developed restraining plate test fixtures for open- and closed-package testing based on customer needs."
Companies offering established testing technologies with known R&D statistics can also reduce customers' development costs. "The fact that ASTM has documented many of these widely used test methods and that FDA has adopted them as consensus standards provides the opportunity to adopt these methods for new products and processes with less validation time invested," says Franks.
Streamlining established methods also saves packaging manufacturers money. "We are always looking for ways to increase the value of leak testing equipment to the customer," says Martin Bryant of Uson L.P. (Houston). "Our latest tester, Vector, has more-powerful processing capability. This enables it to interface easily with other equipment while testing faster."
Going High Tech
Testing companies touting high-tech package testing options rely on their high degree of sensitivity and accuracy to lure customers. Packaging Technologies & Inspection LLC (PTI; Tuckahoe, NY) offers an airborne ultrasonic test method that can detect defects and voids in heat-seal layers and foreign materials in seals.
"The proof is in the results of the data," says Jack Richtsmeier, business development manager for Sonoscan Inc. (Elk Grove Village, IL), a maker of acoustic microimaging equipment. "AMI is extremely sensitive in detecting air gaps or disbonds, which typically come in the form of cracks, voids, and channels. AMI offers a unique advantage to the packaging industry by providing an image or roadmap of the interface between two materials (i.e., the seal zone)."
Sometimes, however, the sensitivity of new technologies can prevent them from being readily embraced, says Ron Pilchik, business manager of the medical package integrity test unit of Mocon Inc. (Minneapolis). Mocon recently won ASTM approval for a technology that uses infrared-based sensing of a CO2 trace gas to identify defects. The method can detect channels as small as 0.004-in. diam in the seal between a porous lid and tray and 0.002-in. diam pinholes in the tray.
"The Mocon method, or any other emerging sensitive, nondestructive method, can and will show defects not currently being detected," Pilchik explains. "The user of the method must be confident that these positive results are real and not false."
Lack of consensus on what size defects are problematic further complicates matters. And though the question is being researched (see sidebar), answers will be years in coming.
The costs and testing time associated with some newer technologies can also make manufacturers less likely to embrace them, says Donald Barcan. Barcan is president of Donbar Industries Inc. (Long Valley, NJ), a medical package consulting firm. Ultrasonic testers, for instance, can cost more than $100,000, and the time to test one package can be more than 30 seconds. "The challenge for the 21st century is to make the equipment affordable and reduce the time that it takes to complete the test," Barcan says.
Several new technologies are being helped along by recently approved ASTM standards. "New standards are a way in which new technology or methods can be introduced, while lessening the risk perceived by companies that otherwise may have continued to use older methods," says Uson's Bryant.
In the ASTM peer review process, interested parties propose test methods. These folks develop supporting data to present to an ASTM subcommittee, explains Pilchik. If the method and data are acceptable, the subcommittee, and eventually the full committee, will vote on approval. "It's a rigorous process that leads to good technology," says Pilchik.
ASTM viewed a presentation about PTI airborne ultrasound technology (ABUS) at its fall meeting. The group has asked to see the equipment at its next meeting in spring of 2004, says Tony Stauffer, president of PTI. ASTM approval is generally a one-year cycle, so the technology could win approval as early as fall, or in 2005. PTI is working to generate data that will be used to support the establishment of a new ASTM method using the ABUS technology. Gathering supporting data for ASTM is time consuming and expensive, says Stauffer, but these hurdles are designed to keep marginal products from passing.
Testing companies would like to see even further new standards and revisions from ASTM. Franks applauds the introduction of test methods for medical trays using porous barrier materials. "However, similar or alternate methods need development for a larger array of package forms," he says.
Uson would like to see more standards for nonsubjective testing and more guidance for companies on "the type and magnitude of leaks they should be testing for," Bryant says.
Pilchik is hoping for a revision of the ASTM standard for visual inspection. "As I often say in public forums, the medical device industry employs leading-edge technologies for its products. Yet, the industry approves packages, the final defenses against microbial contamination, merely by looking at them," Pilchik says. "This method is due for revision soon, and I hope it will be considered seriously for significant change."