Vacuum technology creates, measures and maintains gas pressures below the surroundings for experiments and manufacturing. Pumps remove gas while leaks, permeation and outgassing replenish it. Clean surfaces and appropriate materials can therefore matter as much as nominal pump capacity.
In a simple steady model, a gas throughput balanced by effective pumping speed gives . Connecting pipes reduce that speed through their vacuum conductance. The model assumes a specified gas, flow regime and suitable pressure-gauge interpretation; a pressure reading is not automatically a composition-independent measurement of every residual species.[ref]
New to topics? Read the docs here!