You live in a city where the atmospheric pressure is 101.3 kPa (14.69 psi). If you take a sealed cylinder, pressurise it to 355 kPa (51.489 psi) above the atmospheric pressure and connect pressure gauges to the vessel.

Please calculate the following:

1. What is the gauge pressure?
2. What is the absolute pressure?

If you do not have a weather station close by to give you the atmospheric pressure but do have a gauge pressure gauge and an absolute pressure gauge.

1. How could you get an accurate indication of the atmospheric pressure?

2. Provide the names of any two over pressure relief devices and explain the

operating principle of one of them.

3. Briefly explain two commonly used noise reduction techniques in Instrumentation.