More and more, the practice of nondestructive testing continues to lure cost-conscious manufacturers.
By John Conroy
Nondestructive testing continues to be the Holy Grail for medical device and pharmaceutical manufacturers facing cost pressures and the usual regulatory concerns.
In the testing arena, the most obvious trend is the industry’s search for nondestructive methods, says Steve Franks, executive vice president of T.M. Electronics (Boylston, MA). However, the medical device industry is so tied to Tyvek packaging that there are just a limited number of test processes available to do that.”
In the past year, a few manufacturers have introduced nondestructive techniques that work in a limited number of production settings. Cost and type of product are determining factors, says Franks. The question is: How much value does the test put into the product?
Franks believes the aspects share equal weight. “I think it’s both. For an expensive product, you can afford to add some value.” Orthopedic devices are one such example, he says. Customers are less likely to seek nondestructive tests on commodity products such as catheters and other volume-production devices, Franks says.
Generally speaking, “you can find a way to nondestructively test a product,” the executive points out. With most devices, “you can find a way to get air into it without harming it. That’s pretty straightforward.”
The industry continues to work on determining at what size leaks become harmful, Franks says. “These are not new issues, but people in the instrumentation side are looking at it.” Researchers at Michigan State University (East Lansing, MI) are hard at work, for example, exploring packaging sizes and damage assessments, he reveals.
T.M. Electronics has a relatively new chamber tester that features a high sensitivity level that can “home in on very small leaks,” Franks says. Called the Solution C, the tester was introduced in 2003. A high-resolution, pneumatic leak and flow tester, it is combined with a custom-engineered chamber fixture to test products, sealed packages, or medical devices for leakage.
The Solution C allows operators to store up to 100 different functional programs. It also gives them the ability to link several programs to design a sequence of tests that can suit a specific need, according to Franks. The product’s touchscreen menu operation allows the operator to easily control the test parameters, examine statistical analysis of results, or download data files easily, he adds.
“Nondestructive testing is the brass ring out there,” insists Steve Bunnell, Mocon’s sales and marketing manager. A new test system from Mocon (Minneapolis) combines two test modes. A leakage-testing mode measures pressure loss and a seal-strength mode measures burst test. Mocon is selling the Lippke 2500 SL system for the first time in the United States after acquiring Lippke of Neuwied, Germany, in 2004. Another new system, the Lippke blister tester VC 1380, automates the methylene blue-dye test for blister packs, ampules, and vials.
“We haven’t had these capabilities before,” says Bonnie Knowles, a Mocon sales representative, referring in particular to the water vacuum dye tester. Both Lippke products have been sold in Europe for several years, she notes. It’s the first time they’ve been available in the United States.
The fully computerized 2500 SL system has a flow booster to test trays with Tyvek lids for burst strength, says Bunnell. The system also accommodates pouches with Tyvek lids. In addition, it enables leak testing on flexible, semirigid, and rigid packages, and seal-strength testing on flexible and semirigid packages. In the leak testing mode, a self-adhesive septum is used to ensure a perfect seal for the injection of air, according to the company. After mounting the package onto the needle-head assembly, the pressure builds up in the package until it reaches a preselected level. It is then held at a constant level for the required settling time.
In the 2500 SL’s seal-strength testing mode, the septum is applied to the package and mounted onto a needle head assembly.
The 2500 SL computerized system is well-suited for R&D and quality control settings, Knowles says. A sister version, the 2000 SL, is designed for use on the production line.
Given the capabilities of the new tools, the Mocon crew “would like to see more people do more testing,” Knowles says. Notes Bunnell: “In the past it’s always been a case of ‘if it ain’t broke, don’t fix it.’ ” Device manufacturers have been content to submerge packages in water in order to look for leaks.
Another company actively engaged in package integrity testing is Test-A-Pack (Orchard Park, NY), which has a full line of seal-strength, integrity, and test fixture systems. The company’s 2700-series integrity tester provides a simple visual method for verifying the integrity of nonporous packages, according to a company representative. Its 2600-series seal-strength tester, meanwhile, allows testers to simply press a button for automatic testing and display of testing parameters.
Test-A-Pack also offers a range of closed-package test fixtures for testing completely sealed packages. These feature a sensing probe design that reportedly provides reliable and accurate results for the burst or creep testing of blister packs, lidded trays, and sealed pouches. The company also makes open-package test fixtures with similar features.
Jim Halling, another Mocon sales representative, says manufacturers “are not really using quantitative methodologies to test packages.” The visual approach will continue “until FDA wants to crack down on that.”
In the past year, Pat Nolan, chief operating officer of package testing service for DDL (Eden Prairie, MN), says the government agency may be doing just that. “What we’ve seen is a little bit more of a trend toward FDA clamping down and being more attentive to packaging operations. A lot of our clients are calling us to say they’ve got an FDA inspector on-site.”
Nolan presumes the closer scrutiny is related to poor packaging seals, although he says he has seen “no warning letters or data” to support his speculation. Anecdotal evidence, though, indicates that FDA has noticed enough irregularities to insist that auditors “look at packaging operations. It is a very important aspect of the whole process that a sterilized device is indeed sterilized.”
During 12 years of operation, DDL has been a pioneer in providing packaging validation services, having done “hundreds of validation protocols,” according to Nolan. The company recently has put some marketing muscle behind its seal, strength-test, and packaging integrity services. The company has also launched a new value-added effort called PackAdvice. The service is DDL’s attempt to add value to “what we’ve always done,” Nolan says.
“We don’t just do the testing and say, ‘Here’s your data,’ ” he notes. He likens the validation support “to an accountant doing your taxes and being there on an audit to support you with the IRS.”
DDL is also repackaging its services, partially in response to cost pressures. The issue has risen recently after several years in which “cost was not much of a factor at all,” Nolan says. Today, the supplier is seeing clients holding the purse strings tighter. Citing one example, the COO says DDL lost a project worth several thousand dollars because a competing firm underbid the Minnesota supplier by $75.
Although it’s far from a prevailing trend, DDL has started to lose projects either to in-house testing or competing suppliers. “It’s not to the point where we’re losing market share or anything like that,” Nolan emphasizes. For three to four years, the company has been feeling pressure to raise prices, he reports.
For Uson (Houston), business has been “slowly improving,” says Martin Bryant, product manager for the equipment provider. The company took in more business in the last quarter of 2004 than it had through the preceding months of the year. In particular, customers have been looking for multiunit installations. The nature of client inquiries has given Bryant the impression that “testing is moving out of the lab and into the production line.” Customers are buying equipment primarily for audit testing.
Uson’s Qualipak packaging integrity tester is a nondestructive system “positioned to replace destructive underwater immersion testing,” Bryant points out, adding “Uson hangs its hat on nondestructive testing.”
The Qualipak line of leak testers and pressure-decay leak testers is designed to replace the destructive and sometimes unreliable bubble and blue dye immersion tests.
In addition, the line is designed for testing of sachets, pouches, pillow packs, bags, lidded trays, and blister packs for leaks without the need for chemicals or other trace media. With this method, small leaks are identified quickly, Bryant adds.
He also mentions that this method of testing close to the packaging line can help reduce quarantine lot sizes and quickly bring attention to problems. Such steps can help companies save time and resources.
Uson also offers pressure-decay leak testers, trace-gas detectors, and other leak detection systems. The company’s pressure-decay testers can be designed to test rigid containers quickly and with high levels of sensitivity. They are particularly effective at detecting small leaks in induction-sealed containers, even when filled and with a closure in place, says Bryant. This nondestructive testing can incorporate fixtures, material handling, and reject segregation.
In addition, Uson’s trace-gas detectors use helium or another penetrating gas inside the pack, along with a sensitive detector. This system is designed to accurately locate leaks and can be used in either a handheld probe version or a mass spectrometer.
Working primarily with microelectronics customers, Sonoscan (Elk Grove Village, IL) offers nondestructive acoustic microscope imaging to check bonding strength and ensure the sterility of some medical device packaging, says Steve Martell, technical marketing manager for the company. The higher-frequency ultrasound techniques “look for proper bonding of homogenous materials.” The technology enables users to examine the bonding between the seal and the foil or the package itself, according to Martell.
The technology also enables device manufacturers to scout small potential leaks by actually examining the width of the bond path, the marketing manager points out. Width specifications vary. Some military specs stipulate that the packaging have at least half of the normal width of the bond, Martell says. “Less than that and it’s a process problem you’d have to double-check.”
Manufacturers can use the technology to keep products on the line while checking to determine whether their machinery is off-kilter, according to Martell. Depending on the type of scanner in the ultrasound machine, the technique “can see down to about a 5-micron width and range up to a gross 250 microns.”
For several industries, bonding certainly presents its share of manufacturing concerns, but the packaged product still has to withstand the rigors of the road. “If you were to draw parallels among the pharmaceutical, medical, and semiconductor sectors, shipping is the worst thing that ever happens,” asserts Dave Huntley, general manager ofLansmont (Monterey, CA).
The supplier specializes in transportation-monitoring instruments such as data loggers, temperature recorders, and vibration measurement systems. Lansmont serves different industries with products as diverse as semiconductor wafer inspection systems and OTC drugs. However, shipping can take an equally expensive toll on each, Huntley says.
Both examples have intrinsically high values. The wafer inspection system has a high dollar value, while the drug’s value rests in its lethality if contaminated. “Our specialty is the auditing of, or validation of, that movement of product. It’s critical,” Huntley remarks.
Consider, he says, all the variables a manufacturer confronts when it ships a product: different cargo companies such as FedEx and DHL, traffic jams, rainstorms, and rough handling, for example.
In the medical device and pharmaceutical sectors, Lansmont handles a high number of temperature audits of shippers in order to ensure that protein-based products, for instance, are safely transported. “If you’ve got a product to be maintained between 2° C and 8° C, we can validate or audit that,” says Huntley.
In addition, Lansmont has succeeded in lowering the prices of its trademark Field to Lab instruments and services to make them more attractive to cost-conscious customers, Huntley says. “When it was tens of thousands of dollars to buy advice, it was too costly. Now we’re able to get them down to just under $10,000 to measure a lot of different variables. It’s a lot easier to swallow. The more we do that, the more the government-driven agencies will do that as well.”
Shock and drop testing is one area where Lansmont has made headway in measuring the sensitivity of palletized shippers, for instance, the general manager says. Measuring heat is relatively easy compared to other tasks, he explains. “You can put your hand over a radiator. To measure how hard somebody hit something is more complicated.” The supplier tries “to replicate what actually happens to the product when shipped.”
Shipping risks have also attracted the attention of the Chinese government, Huntley points out. The China Packaging Research and Testing Center in Tianjin, for example, is currently conducting a major study to characterize such risks. The center’s material-testing site currently houses instruments for testing the physical properties of packaging materials.
Twenty Lansmont data recorders have been deployed in China to analyze more than 50,000 shock and vibration events. In addition, 360 different measurements and variables are being recorded by the machines.
Data from the test, which concludes in late 2005, are uploaded to a Web site for analysis by Lansmont workers in California. They will eventually look to replicate the test results in a laboratory. A similar test, directed by Michigan State University researchers, is in the works for India.