buoyancy-compensator.com---scuba bcds, bcd wings, sidemounts bcds, technical bcd bladders!
home page about us products contact us site map FAQs

Home >> technical FAQs >> when need a new diving gauge?


When need a new diving gauge?

Scuba diving gauges can be used to obtain three vital pieces of information: air consumption, depth and time. This critical information enables the diver to avoid running out of air and stay within a safe depth of water. A submersible pressure gauge or monitoring console is used to monitor air consumption. This pressure gauge is usually attached to the high pressure port of the first stage regulator to measure the pressure in the scuba tank.

Initially, the tank may be filled at a dive shop to about 200 bars or 3000 psi. But the pressure will continue to decrease as the diver breathes and uses up the air under the water. This gauge is vital because it helps the diver to reserve adequate air in the tank to come up to the surface safely. It also allows the diver to retain air to inflate the buoyancy compensator device and prevent the tank from being filled with air and moisture from the ocean. Due to the critical function of this diving gauge, it should be replaced as soon as it gets faulty. Here are some of the common signs of a faulty pressure gauge:

The Gauge Shows a Fixed Reading

When the dial on the pressure gauge remains at the same position, even after you have used up some of the air in the tank, you need to change it. Normally, as you breathe, the air pressure in the tank will decrease, and the gauge will reflect this drop in pressure. The best way to discover this kind of fault is by testing the gauge before diving or through a short test dive for about 10 minutes. Observe the pressure gauge during the test, if it does not show a reduction in pressure, you need to change it.

The Oil in the Gauge is Drained

The pressure gauge contains mineral oil which makes the needle and dial to function properly. When the casing of the gauge gets broken or damaged, the oil could gradually drain out. If this occurs, it can be extremely difficult to obtain the right type of oil to replace the one used by the original gauge manufacturer. In addition, it is very difficult to seal up the casing manually after the oil is replaced. Hence, the best option is to replace the entire gauge.

Diving Gauge Works Properly Before Diving But Fails Under Water

Some pressure gauges give accurate information when they are tested out of water but immediately the diver descends below a particular depth, the pressure gauge malfunctions. Most likely, the water resistance of the gauge has failed. Pressure gauges are meant to provide accurate readings even at a depth of 130 feet below the water surface. So if a gauge fails to show that the pressure in the tank is reducing while the diver is under water, it should be changed immediately.

The Connecting Hose is Leaking

If the hose connecting the pressure gauge to the first stage is broken, the gauge will give inaccurate information. When this occurs, there will always be a short fall in the pressure reading on the gauge. You can easily detect this by using soapy water or by using another pressure gauge for troubleshooting. It is not advisable to repair the hose manually with adhesives. Instead, the entire pressure gauge should be changed so it can provide accurate pressure values.


Anytime you notice any of these signs, it is advisable to change the gauge immediately. Diving with a faulty pressure gauge is extremely dangerous. So always test your gauge regularly, especially before you go on any major diving adventure.


Our Scuba bcd wings technical bladders and diving equipments are exported to the worldwide countries like American, Canada, Italy, Germany, Greece, UK, France, Turkey, Ireland, Spain, Australia, New zealand, Brazil, Argentina, Philippine, Indonesia, Thailand, Singapore, Malaysia, Egypt, Japan, Korea, Russia, Poland, Austria, Mexico, Belgium,Venezuela, Bulgaria, Burma, Chile, Colombia, South Africa, Peru, Costa Rica, Norway, Portugal, Denmark, Finland, Sweden, Gibraltar, Uruguay, Puerto Rico, Hungary, Iceland, Madagascar, Maldives, Mauritius, Netherlands, Panama, Romania, Switzerland etc.

Contact: Richard Mobile: +0086-18942448041 E-mail: sales@buoyancy-compensator.com