All Inflatable PFDs come with an oral tube which a user can use to orally inflate the device. This has many uses:
- It acts as a backup if inflation by automatic means or pulling the inflation handle does not occur.
- CO2 will slowly escape through the fabric of an inflated device over time. Topping up by oral inflation may be required in the event of extremely prolonged immersion.
- Oral inflation is an excellent means to test out and see how much inflation is needed to float you. Your device's Owner's Manual will explain how to test your PFD using the oral inflator.
- As temperatures approach freezing, your flotation device will provide less buoyancy and will inflate slower. At temperatures near freezing, the device should be worn partially inflated with the CO2 cylinder to ensure that some buoyancy is immediately available to you if you fall overboard. You can then use the oral inflator to top up the flotation device after adequate CO2 inflation.
- The oral tube is normally used to deflate an inflatable PFD. Just reverse the oral-inflation tube dust cap and insert it into the valve to release the gas.
There are some warnings to note if you do inflate the vest orally:
- Do not manually or automatically activate the inflator when your flotation device is orally inflated. Doing so will result in excessively high pressure within the inflation chamber, which may cause permanent damage to your device and/or extreme discomfort to you.
- You may not inflate the device to the intended design pressure, which means the device may not perform as intended. It might not provide the necessary buoyancy, floatation performances, or self-righting.