A Depth Gauge is a device for registering the pressure of water around a diver.
Several models are available, which vary in accuracy and in special features The simplest types register pressure only (forcing the diver to be familiar with the pressure/depth relationship for the specific planet). Of similar quality and price are gauges manufactured for diving on a specific world, which calibrate depth in meters (or other local measurement) rather than by pressure. In addition to concerns over reliability, characters should be aware of the danger of diving with a depth gauge calibrated for a different planet.
Depth gauges are worn on a wrist mounting and usually require occasional battery charges for power.
The first gauges were large, bulky affairs, often designed to complement SCUBA equipment. At TL–8, a more elaborate model of depth gauge is a digital unit that records time as well as pressure and specifically processes information on decompression stops and duration. Most sophisticated of all at TL–9 a device which can be programmed to show pressure, decompression data, and depth in meters for any world merely by making some simple entries before diving.