AstraGuard Bacterial/Viral Filters

AstraGuard filters protect both patients and equipment during pulmonary function testing (PFT) by trapping bacteria, viruses, and other airborne contaminants before they can pass through to the spirometer or reach the next patient. For any lab running spirometry, these single-use barriers are the small consumable that keeps cross-contamination out of the breathing circuit.

The collection centers on the AstraGuard Bacterial/Viral Filter with integrated mouthpiece (29-7990-100), a disposable filter built specifically for use with pulmonary function testing. It arrives with the mouthpiece already attached, so there's no separate part to source or fit — the patient breathes directly into a ready-to-use assembly that seals cleanly against the flow sensor. The small, non-threatening profile matters more than it sounds: a bulky filter can intimidate anxious or pediatric patients and skew results, while this lower-visual-impact design helps them relax and produce accurate, repeatable maneuvers.

Because each filter is discarded after a single patient, technicians avoid the labor and infection-control risk of reprocessing internal tubing between tests. High filtration efficiency guards the spirometer's sensitive sensors from moisture and particulate, extending equipment life and reducing calibration drift. That combination — patient protection, equipment protection, and clean workflow — is why disposable PFT filters have become standard practice in respiratory clinics, hospital pulmonary labs, and occupational health screening.

Stocking depth is the practical question here: high-volume labs should order in quantities that match their daily test schedule so a filter is always on hand for the next appointment. If you're outfitting or resupplying a testing station, explore related consumables and instruments in our broader Respiratory category.