Search results
Results from the WOW.Com Content Network
A standard measurement, hood static pressure, provides information on airflow changes that affect hood performance. For hoods designed to prevent exposure to hazardous airborne contaminants, the American Conference of Governmental Industrial Hygienists recommends the installation of a fixed hood static pressure gauge .
In closed caissons the internal pressure may be raised to keep water out. Occupants need to use an airlock for access, and may require decompression stops when exiting. Underwater demolition, for removal of damaged structure in repair work, or to prepare an area for new construction. Underwater surveying: site surveys and geological surveys
The parent of all mercury pressure gauges is the mercury barometer invented by Evangelista Torricelli in 1643. [15] An early engineering application of the mercury pressure gauge was to measure pressure in steam boilers during the age of steam. The first use on steam engines was by James Watt while developing the Watt steam engine between 1763 ...
Compass navigation is a matter of training, practice and familiarity with the use of underwater compasses, combined with various techniques for reckoning distance underwater, including kick cycles (one complete upward and downward sweep of a kick), time, and occasionally by actual measurement, which may involve the length of umbilical deployed ...
A reduced pressure zone device (RPZD, RPZ, or RPZ valve) is a type of backflow prevention device used to protect water supplies from contamination. RPZDs may also be known as reduced pressure principle (RP), reduced pressure principle backflow prevention devices, [1] [2] reduced pressure zone assemblies (RPZA), [3] or reduced pressure principle ...
Example of the widely used Bourdon pressure gauge Checking tire pressure with a spring and piston tire-pressure gauge. Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area.
A permanent downhole gauge (PDG) is a pressure and/or temperature gauge permanently installed in an oil or gas well. [1] These gauges are typically installed in the tubing in the well and can measure the tubing pressure, annulus pressure, or both.
A special form of the Pirani gauge is the pulsed Pirani vacuum gauge where the sensor wire is not operated at a constant temperature, but is cyclically heated up to a certain temperature threshold by an increasing voltage ramp. When the threshold is reached, the heating voltage is switched off and the sensor cools down again.