Similarly, high-level events can be decomposed into one or more low-level events or actions; for example, changing a pressure control valve, sounding an alarm, or signaling an alert.
UV unit: High speed low pressure UV emitter; UV sensor with alarm.
紫外线单元：高速低压紫外线放射器；带报警系统的紫外线传感器。
3
The system uses a vent fan, a manually adjustable backpressure damper, a differential pressure-sensing gage, and an inlet air filter high differential pressurealarm switch.