There’s something about a pneumatic tube system (PTS) that makes risk feel distant. Maybe it’s the speed, maybe it’s the sealed canister, or maybe it’s just the fact that once a specimen disappears into that tube station, it becomes someone else’s problem. But that perception is exactly where the danger begins. When it comes to respiratory specimens, what travels through that system isn’t just a sample, it’s a potential aerosol exposure event waiting to happen at the other end.
During the height of the COVID-19 pandemic, the Centers for Disease Control and Prevention (CDC) made it very clear: pneumatic tube systems could generate aerosols. That language mattered because it acknowledged a truth laboratorians have long understood—movement, agitation, and pressure changes can turn liquid specimens into airborne hazards. More recently, that direct language has softened. Now, the CDC recommends that organizations perform their own risk assessments to determine whether PTS transport is appropriate. On the surface, that sounds reasonable. In practice, it has opened the door for inconsistent decisions, internal pressure, and in some cases, a quiet erosion of safety practices that were once considered non-negotiable.
Contrast that with guidance from the Clinical and Laboratory Standards Institute (CLSI), specifically the QMS28 document titled Laboratory Safety Management. The message there is far less ambiguous: do not transport respiratory specimens via pneumatic tube systems. That clarity is refreshing, but it also puts laboratory leaders in a difficult position when operational demands start pushing in the opposite direction.
Those pressures are very real. Nursing units and emergency departments are often stretched thin. Staffing shortages, patient surges, and throughput expectations all create a strong incentive to use the fastest available transport method. From their perspective, sending a specimen through the tube system is efficient and practical. But here’s the uncomfortable truth: there is no risk to them once that carrier closes and the button is pressed. The risk is transferred entirely to the laboratory professional who opens that canister, often without knowing exactly how the specimen was handled, how tightly it was sealed, or what happened to it during transit.
Let’s be clear about what can happen inside that system. Pneumatic tubes move carriers rapidly through a network of pressurized air. Specimens can be jostled, shaken, and subjected to sudden stops. Even a well-capped tube can leak under those conditions. If a primary container isn’t sealed perfectly, or if a bag isn’t intact, small amounts of fluid can aerosolize within the carrier. When that carrier is opened in the lab, those aerosols don’t stay politely contained. They enter the breathing zone of the person doing the receiving.
What might be in those aerosols? We are not just talking about nuisance exposures. Respiratory specimens can contain pathogens like Mycobacterium tuberculosis, influenza viruses, respiratory syncytial virus, SARS-CoV-2, adenovirus, parainfluenza viruses, and even Bordetella pertussis. Many of these organisms are capable of transmission through aerosols or droplets, and some carry significant consequences for exposed staff. The idea that a thin layer of plastic and a high-speed ride through a tube system somehow neutralizes that risk is simply not grounded in reality.
One of the most common solutions suggested so that PTS transport can occur is that specimens can be double-bagged. It sounds reassuring, and on paper, it feels like a control. But it doesn’t solve the core problem. At some point, someone in the laboratory must open that final bag. If aerosols were generated inside the primary container or within the transport bag during transit, opening that packaging is the moment of exposure. Double-bagging may help contain visible leaks, but it does nothing to eliminate aerosol risk. It’s a control that protects the hallway, not the laboratorian.
So where does that leave us? Stuck between operational efficiency and employee safety? It doesn’t have to. There are workable solutions, but they require commitment and, frankly, a willingness to prioritize safety over convenience. Some organizations have implemented dedicated courier systems or used trained volunteers to transport high-risk specimens by hand. Others have established clear policies that prohibit PTS use for respiratory samples and backed those policies with leadership support, even when there is pushback. Proper packaging still matters, of course—leak-proof containers, secure lids, and appropriate secondary containment—but those are baseline expectations, not substitutes for safe transport decisions.
Communication is another critical piece. Laboratory leaders need to clearly explain the “why” behind these restrictions. This isn’t about being difficult or inflexible; it’s about protecting people from a real and preventable hazard. When nursing and Emergency Department staff understand that the risk doesn’t disappear—it simply shifts—they are more likely to engage in finding workable alternatives. It also helps to share real scenarios, near-misses, or data from internal risk assessments to make the hazard tangible rather than theoretical.
Ultimately, this issue comes down to a fundamental principle of laboratory safety: just because a process is fast and convenient does not mean it is safe. Pneumatic tube systems are valuable tools, but they are not appropriate for every specimen type. Respiratory samples carry inherent risks that are amplified—not reduced—by high-speed, pressurized transport.
Safety isn’t serendipity—it’s science. And the science here is clear. When we send respiratory specimens through a pneumatic tube system, we’re not just moving samples. We’re moving risk, concentrating it, and delivering it directly into the hands—and lungs—of laboratory professionals. The question isn’t whether we can do it, it’s whether or not we should.