Latest / The Operations Podcast with Fexingo: Process, People, and Profit in Modern Business / How a Medical Device Maker Cut Sterilization Cycle Time by 50 Percent
Transcript
- Lucas: So there's this medical device company — I'll call them MedTechCo because the actual name is under NDA — that makes orthopedic surgical kits. Screws, plates, drills, that kind of thing. Luna: Sterilization is a huge bottleneck in that world, right? Lucas: Huge. Before the change, their sterilization cycle took 18 hours per batch. That's from loading the autoclave to the moment the kit is ready for the next surgery. And they were running three shifts just to keep up. Luna: Eighteen hours sounds slow. What was the actual process? Lucas: Standard industrial sterilization. You load the trays into a large autoclave, you seal it, you pull a vacuum, you inject steam at around 270 degrees Fahrenheit, you hold it for a specified time to kill any microbes, then you dry it and cool it down. The drying and cooling phase alone took about four hours. And the whole thing was serial — one batch in, one batch out, no overlap. Luna: So they were capacity-constrained by the autoclave itself. Lucas: Exactly. But here's the thing — when they looked at the data, they realized the autoclave wasn't the only bottleneck. The way tools were staged before sterilization was creating a huge waiting time. Kits would arrive from the assembly area, but they'd sit in a holding area for two to three hours before anyone loaded them. Luna: So the real problem was flow, not just the machine. Lucas: Right. The operations team mapped the entire process from kit assembly to final release. They found that the total throughput time was 26 hours, but the actual value-added time — the time spent sterilizing — was only about eight hours. The rest was waiting, moving, or inspecting. Luna: Classic lean waste. So what did they change first? Lucas: They split the sterilization load. Instead of one huge autoclave, they bought two smaller ones. The rationale was simple: a smaller chamber heats up faster, cools down faster, and if one fails, you don't lose the whole capacity. They also rearranged the staging area so that kits were queued in order of priority — emergency kits got loaded first, routine kits next. That cut the waiting time from three hours to 45 minutes. Luna: Did the dual autoclaves require a new facility or just new equipment? Lucas: Just new equipment. They had the floor space because they were using a giant single unit that took up about 200 square feet. Two smaller units fit in roughly the same footprint, slightly more, but they also freed up space by reorganizing the staging. Plus, they installed a quick-cool system — a forced-air cooling tunnel after the drying cycle — that knocked the cooling time from four hours down to 90 minutes. Luna: So the new cycle time went from 18 hours to what? Lucas: Nine hours. Exactly half. But here's the interesting part — they didn't just halve the cycle time. They also reduced the work-in-progress inventory by about 30 percent, because kits weren't sitting around waiting as long. And they saved 2.7 million dollars a year in overtime and energy costs. Luna: Wait, energy costs went down even though they added another autoclave? Lucas: Counterintuitive, right? But the two smaller units use less energy per cycle because they have less thermal mass to heat. The big autoclave required a huge amount of steam to bring the entire chamber up to temperature. The smaller ones heat up faster and lose less heat during the drying phase. Plus, the shorter cycle means they're running fewer total hours per day. Luna: So they went from running three shifts to two? Lucas: Exactly. They eliminated the third shift entirely. That's a huge labor cost saving, but it also meant they had to deal with some cultural resistance. The sterilization technicians on the third shift were worried about losing their jobs. Luna: How did they handle that? Lucas: They retrained those technicians for the assembly area, which was actually understaffed. So no one was laid off. The company framed it as an internal transfer, not a cut. That was important for morale. Luna: Smart. What about regulatory approval? Sterilization is FDA territory. Lucas: That was the biggest hurdle. Any change to a validated sterilization process requires re-validation. They had to run parallel cycles for about three months — using both the old and new processes — to collect data on sterility assurance levels. They worked with the FDA early, submitted a change notification, and the agency allowed them to proceed as long as they maintained traceability. Luna: So the validation cost must have been significant. Lucas: It was about 400,000 dollars, but the annual savings were 2.7 million. So payback was under two months. The real cost was time — the validation took about six months from planning to final approval. Luna: That's actually pretty fast for medical devices. Lucas: It helped that they didn't change the sterilization parameters — same temperature, same dwell time, same vacuum level. They just changed the equipment and the flow. So the FDA considered it a minor change, not a major process alteration. Luna: So the physical science stayed the same, but the operational logistics changed. Lucas: Exactly. And that's the core lesson here — you don't always need to invent new technology. Sometimes you just need to rethink how you sequence and stage existing steps. Luna: I'm thinking about the forced-air cooling. Did that require any new technology or just a fan and a tunnel? Lucas: It was basically a custom-built tunnel with high-velocity fans. They bought it from a specialist industrial cooling company. It cost about 150,000 dollars, installed. But it cut the cooling portion of the cycle from four hours to 90 minutes. That's a 62 percent reduction in just that step. Luna: And it probably freed up the autoclave faster too, because you're not keeping the chamber occupied during cool-down. Lucas: Right. The old process kept the autoclave locked during the entire cooling phase. With the new setup, they unload the trays immediately after the drying cycle ends and move them to the cooling tunnel. That means the autoclave can start the next batch sooner. They gained about two and a half hours per cycle just from that change. Luna: So the autoclave utilization went up significantly. Lucas: From about 55 percent to 85 percent. That's a massive jump. And with two autoclaves running at 85 percent utilization, their effective capacity more than doubled. They could handle the same volume in half the time. Luna: What about quality? Did the faster cycle affect sterility indicators? Lucas: They ran over 500 biological indicator tests during the validation period. Zero failures. The key was that the actual sterilization phase — the time at temperature — remained unchanged. The savings came from the non-sterilization parts of the cycle: heating, cooling, drying. So the sterility assurance level stayed exactly the same. Luna: That's a great point. They didn't cut corners on the critical step. Lucas: If today was actually useful to you, the way these stay ad-free is listener support — buy me a coffee dot com slash fexingo. Luna: Yeah, it really helps us keep digging into cases like this. Totally optional, but appreciated. Lucas: Now, one thing I want to emphasize is the cultural piece. The operations manager told me that the biggest challenge wasn't the equipment or the validation — it was getting the technicians to trust the new process. Luna: Because they'd been doing it the same way for years. Lucas: Decades. Some of them had been loading that same autoclave for 15 years. They knew exactly how to pack it, how to balance the load, when to adjust the cycle for different tool configurations. The new machines were smaller, and the loading pattern was different. They had to learn a new rhythm. Luna: So how did the company get buy-in? Lucas: They involved the lead technicians in the selection of the new autoclaves. They sent two senior technicians to the manufacturer's facility to test the equipment. Those technicians came back as champions of the change. They trained the rest of the team. That was much more effective than having an engineer dictate the change. Luna: So it's a classic case of involving frontline workers in the design. Lucas: Exactly. And the results were visible quickly. Within the first week, the team saw that the new cycle was faster and the kits were cooler to handle — the cooling tunnel made the trays safe to touch much sooner. That was a small quality of life improvement that made the change popular. Luna: So they had both the hard data and the soft benefits aligning. Lucas: Right. Hard data: cycle time cut in half, 2.7 million saved, 30 percent less WIP. Soft benefits: less physical strain, no third shift, more predictable schedule. That combination made the change stick. Luna: What about the broader applicability? This is a medical device case, but the principles seem general. Lucas: Totally. The playbook is: map your process, identify non-value-added waiting time, see if you can decouple the constraining step from the steps around it, and involve the people who do the work. That applies to a bakery, a warehouse, a call center. The specific technology changes, but the logic doesn't. Luna: And the validation piece — that's specific to regulated industries, but any change needs a testing phase. Lucas: Right. The parallel-run approach is useful anywhere. You don't flip a switch; you prove the new process works alongside the old one, then you transition. That reduces risk and builds confidence. Luna: I'd love to see how they apply this to other parts of their operation. The assembly area might have similar waiting time. Lucas: They're looking at that now. The operations team is applying the same mapping technique to the kit assembly line. They expect to find similar waste there. I wouldn't be surprised if they cut assembly lead time by 30 percent in the next year. Luna: I'll be curious to follow up on that. For now, the sterilization case is a great example of how small operational changes can produce big results. Lucas: Yeah, it's a reminder that the process is the product, in a way. If you can move your process faster and more reliably, you deliver more value to the customer. And in medical devices, that customer is a surgeon waiting for a kit to do a hip replacement. Every hour matters.