Piezoelectric belts- Piezoelectric belts contains a piezo-electric device that responds linearly to changes in length. It measures changes in thoracic or abdominal circumference during respiration. These measurements can indicate inhalation, expiration and breathing strength and can be used to derive breathing rate. The transducer may be used to characterize breathing patterns. The transducer is a solidstate device that requires no excitation. It is comfortable to wear, rugged, reliable and washable.

RIP belts- RIP belts have a wire running through the length of belts in a zigzag fashion. When chest and abdomen expand the inductance of the wire changes which is proportional to the cross sectional area belt encloses. This change in inductance is recorded as signal. To ensure quality signals, RIP belts should be placed at the standard locations: near the nipple line (or mid-chest) and just above the belly button.