Insufficient Breath Sample or Shy Lung
Evidential Breath Testers (EBT’s) are engineered to automatically capture a breath sample when analyzing for the presence of alcohol. There are two critical conditions which must be met in order for an automatic breath sample to be taken. First, the subject must provide a minimum volume of breath (1200 cc’s of breath for the Alco-Sensor IV and 1350 cc’s of breath for the Alco-Sensor V). Second, the subject must reach a breath flow drop off point. When both conditions occur, the instrument’s fuel cell automatically opens to capture 1cc of breath sample. However, when your subject will not or cannot provide the minimum volume of breath and reach the breath flow drop off point, it is referred to as “insufficient breath sample” or “shy lung”. Here are the most common reasons for “insufficient breath sample” or “shy lung” and ways to overcome it:
- Improper instruction to the subject: This is the number one reason Breath Alcohol Technicians (BAT) fail to obtain a sufficient amount of breath. It is very important to provide the proper instructions to your subject. I often hear students in a training class instruct their test subjects using phrases like, “blow hard” or “blow long and hard”. If you subject blows too hard, the instrument will likely render an error message and your subject is going to run out of breath before they reach that critical breath flow drop off point. The clearest instruction you can provide is…“Take a deep breath. Hold if for just one second. Blow long and steady until I tell you to stop.” It is also a good idea to ask them if they understood the instructions AND if they didn’t, take an individual mouthpiece and provide a demonstration.
- Subject is “faking it”: If you think your subject is “faking it”, try to take a manual breath sample. Your Alco-Sensor is engineered to allow you to capture a manual breath sample and gives you three chances to do so before it displays a “Void 6” or “Insufficient Sample” error message in the display window. Between each attempt, continue to give good instructions as outlined above. From the previous attempt, mentally note when the subject reached that breath flow drop off point so you know when to press your manual trigger.
- Subject has a medical condition: The DER should notify you if there is a known medical condition and proactively order a manual breath sample be taken. However, there may be times when you will not be made aware of this. As the BAT you are empowered by the DOT federal regulations to attempt the capture of a manual breath sample. In any case give clear instructions to your subject at all times.
- You have a clogged mouthpiece: A mouthpiece should be removed from the package by tearing at the pouch perforation or peel back flap. Never remove a mouthpiece by jamming the end through the plastic pouch. This may force plastic into the mouthpiece, making air flow impossible.
- Subject is too nervous: That which is unfamiliar can often times make someone feel anxious or nervous. Take a little time to make your subject feel comfortable by communicating the process and demonstrating how to provide a good breath sample. If they cannot overcome their nervous state, try to take a manual breath sample.
Manual breath sampling for alcohol testing is preferred over reports of “Insufficient Sample”. Being aware of primary causes for “Insufficient Sample” and some of the ways of overcoming this obstacle will render more completed tests and more efficient operations.