A basic spirometry test, the most common type of pulmonary function test, typically takes about 15 to 45 minutes from start to finish, though the actual blowing maneuvers account for only a fraction of that time. If your doctor orders additional tests such as a bronchodilator response assessment, lung diffusion capacity measurement, or full cardiopulmonary exercise testing, the appointment can stretch to an hour or more. The wide range depends on which specific tests are ordered, how quickly you produce acceptable results, and whether the lab bundles multiple tests into a single visit.
Spirometry Alone Is the Quickest Option
Spirometry measures how much air you can blow out and how fast you can blow it. You take a deep breath, seal your lips around a mouthpiece, and exhale as hard and as long as you can. A technician coaches you through each attempt, checking each curve on a screen for quality. Most people need three to eight acceptable blows before the technician is satisfied, and each blow takes only a few seconds of actual effort. Between blows you rest for a minute or so to catch your breath. Factor in the time for a technician to explain the procedure, position you correctly, and enter your data, and a straightforward spirometry session runs roughly 15 to 30 minutes.
What stretches that time is repeatability. The technician needs at least three good-quality efforts where your results are close to each other. If your first few attempts have air leaks, hesitant starts, or coughs mid-blow, those don’t count. Younger, healthy adults who follow coaching well sometimes wrap up in under 15 minutes. Older adults or people with severe lung disease may need more attempts and more rest between efforts, pushing the visit closer to 30 or even 45 minutes for spirometry alone.
Adding a Bronchodilator Response Test
Doctors frequently want to know whether your airways open up after inhaling a short-acting bronchodilator, usually albuterol (salbutamol). This is the standard way to check for reversible obstruction, which helps distinguish asthma from conditions like chronic obstructive pulmonary disease (COPD). The test adds a significant chunk of waiting time to your appointment.
The process works like this: you complete your baseline spirometry, then inhale the bronchodilator through a spacer or nebulizer. After that, you sit and wait before repeating spirometry. Professional guidelines from the American Thoracic Society and European Respiratory Society recommend waiting at least 15 minutes between pre- and post-bronchodilator spirometry.
In practice, the ideal wait is often longer than 15 minutes. Research on adults with obstructive lung disease found that the average peak bronchodilator effect on one key measurement occurred at around 20 minutes after inhalation, while another measurement peaked at about 30 minutes.1PubMed Central. Determining the optimal time to assess the reversibility of airway obstruction A study of asthmatic children reached a similar conclusion, finding that a minimum interval of 20 minutes was needed to capture the maximal bronchodilator response in most kids.2PubMed. Determining the time to maximal bronchodilator response in asthmatic children Many pulmonary function labs therefore use a 15-to-20-minute waiting period as their standard.3PubMed. Effect of extending the time after bronchodilator administration on identifying bronchodilator responsiveness in a pediatric pulmonary clinic
So a bronchodilator reversibility test essentially doubles your time in the lab. You do the first round of spirometry (15 to 30 minutes), wait 15 to 20 minutes for the medication to take effect, and then repeat the spirometry (another 10 to 15 minutes, usually faster this time because you’re warmed up). Total clock time is typically 45 minutes to just over an hour.
Lung Diffusion Capacity Testing
A diffusion capacity test, often written as DLCO on your order form, measures how well gases cross from your lungs into your bloodstream. It is commonly ordered alongside spirometry for people with conditions like pulmonary fibrosis, emphysema, or unexplained shortness of breath. The test itself is relatively quick per maneuver: you breathe in a special gas mixture containing a tiny amount of carbon monoxide and a tracer gas, hold your breath for about 10 seconds, then exhale steadily. The machine analyzes how much carbon monoxide your lungs absorbed during that single breath-hold.
The time cost comes from repetition and mandatory rest intervals. Guidelines recommend waiting at least four minutes between duplicate measurements to let residual test gas clear from your lungs.4European Respiratory Journal. Impact of shorter time interval between duplicate DLCO measurements Since you typically need at least two acceptable maneuvers, that’s a minimum of four minutes of sitting between them, plus the time for each maneuver itself and the technician’s quality checks. A DLCO test on its own usually takes 15 to 30 minutes. When it’s bundled with spirometry, expect the combined visit to run 30 to 45 minutes if no bronchodilator test is included, or an hour or more if one is.
Full Lung Volume Measurement
Some orders include a test for total lung capacity, residual volume, and related measurements. This is often done in a body plethysmograph, a clear, phone-booth-sized chamber you sit inside while breathing through a mouthpiece. The technician closes the door briefly while you pant gently against a closed shutter, and pressure changes inside the box let the equipment calculate how much air your lungs hold at every stage of breathing.
The actual measurement takes only a few minutes per trial, but people sometimes feel uneasy in the enclosed space, which can slow things down. You may need several attempts, and the technician will open the door between rounds. Plan for roughly 15 to 20 minutes for plethysmography alone. When lung volumes are added to spirometry and DLCO as a “complete pulmonary function test” package, the entire visit commonly runs 60 to 90 minutes.
Cardiopulmonary Exercise Testing
A cardiopulmonary exercise test (CPET) is the longest common pulmonary test. It combines breathing measurements with heart monitoring while you exercise, usually on a stationary bike or treadmill. The European Respiratory Society’s standardized protocol calls for at least three minutes of rest, three minutes of unloaded pedaling or slow walking, eight to twelve minutes of progressively harder exercise, and then two to three minutes of recovery.5European Respiratory Review. ERS statement on standardisation of cardiopulmonary exercise testing in chronic lung diseases
That exercise portion alone adds up to roughly 16 to 21 minutes. But the appointment is much longer because of setup: you’ll have ECG electrodes placed on your chest, a blood pressure cuff fitted, a pulse oximeter clipped on, and a face mask or mouthpiece connected for breath-by-breath gas analysis. Calibrating the equipment takes several minutes. Many labs also perform baseline spirometry before the exercise portion. Including setup, the exercise itself, a monitored cooldown, and cleanup, a CPET appointment typically runs 45 minutes to an hour and a half. If your doctor ordered it specifically to evaluate unexplained breathlessness or to assess surgical fitness, expect to block out at least 90 minutes.
What About Children and Preschoolers?
Spirometry takes longer with young children, partly because the technique requires coordination that small kids are still developing. A study of preschoolers aged three to six found that children needed an average of about 6.6 attempts per maneuver to produce acceptable curves before bronchodilator use, and around 5.1 attempts afterward.6Jornal Brasileiro de Pneumologia. Feasibility of spirometry in preschool children By comparison, a cooperative adult often achieves acceptable results within three to five blows. The extra attempts mean more coaching, more rest breaks, and a longer visit overall. Parents should expect a pediatric spirometry session to run 30 to 45 minutes or longer, especially for children under five.
Performance improves with age. Three-year-olds had the hardest time producing usable curves, while six-year-olds performed much more reliably. If your child is being tested for the first time, the technician may spend extra time turning the procedure into a game, using animated software that rewards good blows with on-screen animations. That playful approach improves results but also adds minutes to the clock.
Impulse Oscillometry as a Faster Alternative
Not everyone can perform the forceful exhale spirometry requires. Very young children, frail elderly adults, and people with severe breathlessness sometimes simply can’t blow hard and long enough to get usable data. Impulse oscillometry (IOS) is an alternative that measures airway resistance while you breathe normally through a mouthpiece. The device sends gentle sound-wave pulses into your airways and analyzes how those pulses bounce back. Because it requires only quiet, relaxed breathing and minimal patient cooperation, it can be done in people who are unable to perform spirometry.7PubMed Central. Impulse oscillometry: The state-of-art for lung function testing
An IOS measurement typically lasts 30 to 60 seconds of tidal breathing per trial, and two or three trials are usually collected. Including setup and data review, the test can be done in under 10 minutes for a cooperative subject. It is not a replacement for spirometry in all clinical scenarios, but when speed and ease matter, it is a useful option that some pediatric and geriatric clinics prefer as a first-line screen.
Home Spirometry and How It Compares
Portable spirometers have become more common, especially for people with chronic lung conditions who need to track their function between clinic visits. Home devices measure the same basic parameters as lab spirometers, and studies of patients with severe COPD have found that daily home readings are reliable enough to track changes over time, though home values tend to be slightly lower than clinic values, likely because there’s no technician coaching you through each blow.8Dove Press / PubMed Central. Daily home-based spirometry during withdrawal of inhaled corticosteroid in severe to very severe chronic obstructive pulmonary disease
A single home spirometry session takes about five minutes once you’re familiar with the device. You power it on, perform three good blows, and the device stores or transmits the results. There’s no waiting room, no travel time, and no technician scheduling. The tradeoff is accuracy: without someone watching for air leaks, coughs, or half-hearted efforts, individual readings can be less precise. Over time, though, the day-to-day trend data from home spirometry is valuable for spotting early declines that might not show up during quarterly clinic visits.
Practical Tips to Keep Your Visit Shorter
Most of the time variability in pulmonary function testing comes from how quickly you produce acceptable results. A few things genuinely help speed the process along:
- Avoid smoking beforehand. Most labs ask you to refrain from smoking for at least four to six hours before testing, because recent smoking temporarily changes airway caliber and diffusion measurements.
- Skip heavy meals. A full stomach pushes up on your diaphragm and can reduce the volume of air you move. Eat lightly two to three hours before the test.
- Hold off on bronchodilators if instructed. Your doctor may ask you to skip your regular inhaler the morning of the test so baseline readings reflect your untreated airway function. Using it by mistake means the technician may need to reschedule or add extra steps.
- Wear loose clothing. Tight waistbands and restrictive shirts limit chest expansion. Comfortable clothes let you take a full breath more easily.
- Listen to the technician’s coaching. The biggest time sink is unusable blows. If the technician says “blast it out harder” or “keep blowing, keep blowing,” they’re trying to prevent a repeat. Following their cues closely often cuts several attempts from the session.
Arriving a few minutes early to handle paperwork also helps. Most labs have you fill out a questionnaire about your smoking history, medications, and symptoms before testing begins. Getting that done in the waiting room rather than in the testing room keeps the equipment schedule on track.
When Multiple Tests Are Bundled Together
It’s common for a pulmonologist to order a “complete PFT” that bundles spirometry, bronchodilator reversibility, lung volumes, and diffusion capacity into one visit. Labs have their own preferred sequencing, but a typical order is spirometry first, then lung volumes by plethysmography, then DLCO, then the bronchodilator, then repeat spirometry. This sequence works because the bronchodilator waiting period can overlap with other tests, saving total time.
Even with efficient scheduling, a complete PFT panel usually takes 60 to 90 minutes. If exercise testing is included as well, the appointment can stretch past two hours. When your referral form says “PFTs,” it’s worth calling the lab ahead of time to ask which specific tests are ordered and how long to expect. Some labs schedule complete panels in dedicated time blocks and will tell you upfront to plan for 90 minutes. Others tack tests on sequentially and may underestimate the total time on the phone.
Why Repeat Visits Sometimes Happen
Occasionally, a pulmonary function lab will ask you to come back for a second session. This usually happens for one of a few reasons. Sometimes the data quality on the first visit was poor, perhaps because you were having a bad breathing day, felt unwell, or couldn’t coordinate the maneuvers well enough. Other times, your doctor sees the initial results and wants an additional test that wasn’t originally ordered, like a methacholine challenge to provoke airway narrowing and confirm asthma. A methacholine challenge is its own procedure, typically taking 60 to 90 minutes, and most labs won’t add it to an already long appointment on the fly.
Serial testing over weeks or months is also common for monitoring. People with interstitial lung disease, cystic fibrosis, or post-transplant recovery may have spirometry or DLCO repeated every few months to track disease progression or treatment response. Each individual follow-up visit tends to be shorter than the initial one, because the technician doesn’t need to explain the procedure from scratch and you already know what to expect. A follow-up spirometry-only visit typically runs 15 to 20 minutes.
Methacholine and Other Provocation Tests
If standard spirometry looks normal but your doctor still suspects asthma, a bronchoprovocation test may be ordered. The most common version uses inhaled methacholine in increasing doses. You perform spirometry at baseline, inhale a low concentration of methacholine, repeat spirometry, and then inhale a slightly higher concentration, repeating the cycle until your lung function drops by a predetermined amount or you’ve completed the full series without a significant drop. Because each step requires a fresh spirometry effort and a brief waiting period, the entire test can take 60 to 90 minutes. If your airways do react, a bronchodilator is given at the end and another spirometry is done to confirm your function recovers, which adds another 15 to 20 minutes.
Exercise-induced bronchospasm testing is a related but different provocation. Instead of inhaling a chemical trigger, you exercise vigorously for six to eight minutes and then perform spirometry at intervals for 15 to 30 minutes afterward. Total time runs about 45 to 60 minutes including setup and monitoring. These provocation tests are less commonly ordered than standard spirometry but are important for confirming or ruling out asthma in people whose baseline numbers look normal.