Spirometry
Occupational Spirometry: Keeping Your PFT Results Defensible
July 6, 2026 · 5 min read
Spirometry shows up across occupational health — respirator medical evaluations, surveillance programs under substance-specific OSHA standards, and the NIOSH Coal Workers' Health Surveillance Program. Wherever it appears, the result is only as defensible as the practices behind it: the instrument's calibration, the technician's training, and the quality of each maneuver.
Calibration verification — every testing day
A spirometer should have its accuracy verified with a calibration syringe (typically 3 liters) before testing, following the manufacturer's procedure and the consensus technical standards the device is validated against. Log every check — a result without a calibration trail is the first thing challenged when a case is contested.
The syringe itself needs care too: it should be maintained and periodically checked, not treated as a lifetime-accurate reference.
Technician training
Coached, maximal-effort maneuvers are a skill. For NIOSH CWHSP testing, technicians must complete a NIOSH-approved spirometry course; for other occupational programs, formal training to the same standard is the benchmark worth holding your program to. A trained technician recognizes a bad curve in real time instead of filing it.
Test quality: acceptable and repeatable
Current ATS/ERS spirometry standards grade each session on acceptability (good start, no cough or glottis closure, adequate exhalation) and repeatability between the best efforts. Modern computer-controlled spirometers grade this automatically — which is exactly why software and instrument versions matter when results are reviewed years later.
Consumables are part of the result
Single-use flowtubes, filters, and mouthpieces exist to protect both the employee and the measurement. Reusing single-use sensors or substituting non-OEM consumables changes the flow characteristics the instrument was calibrated for. Stock genuine consumables and treat the reorder as part of the program, not an afterthought.
The paper trail
For each employee: the test record with quality grades, the technician's identity and training, and the instrument's calibration-verification log for that day. Foster supplies and services the spirometers we sell — EasyOne and Benson computer-controlled instruments — plus the genuine flowtubes, filters, and calibration syringes that keep the whole chain intact.
EasyOne and Benson spirometers, genuine flowtubes, filters, and calibration syringes — shipped nationwide, with calibration and service from the same team.
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