Are pressure transmitters subject to mandatory calibration?

Meters that are subject to mandatory inspection refer to those used in areas such as safety protection, healthcare, environmental monitoring, or trade settlement. As listed in the catalog of meters requiring mandatory inspection, any pressure transmitter that meets the aforementioned criteria is considered a meter subject to mandatory inspection; otherwise, it is not

In my opinion, if the pressure gauge in the same area is rated as Class A, then a pressure transmitter is not necessary.

In chemical plants, pressure sensors and pressure gauges are commonly used to monitor and control pressure in order to ensure the safety and stability of the production process. Regarding your question, in general, pressure sensors installed on pressure vessels/pressure pipelines in chemical plants are typically classified as Class B instruments, as they are used to measure and control physical quantities such as pressure. However, in certain specific situations, such as pressure sensors used in hazardous areas (e.g., those that are flammable, explosive, toxic, etc.), more stringent safety requirements may apply, and such sensors may be classified as Class A instruments. As for ordinary local pressure gauges, they are usually also classified as Class B instruments. However, if these pressure gauges are used to monitor and control safety-related parameters such as the liquid level, temperature, and pressure in containers or pipelines, they may need to meet more stringent requirements to ensure safety and reliability.

I remember that for pressure pipelines and pressure vessels, regardless of whether there are pressure transmitters or not, local pressure gauges must be installed. So it is sufficient to send the local pressure gauge for inspection. I’m not sure if I’m saying the wrong thing; could any experienced person correct me?

The pressure transmitters for major hazard sources belong to Class A

Classification of pressure gauges subject to mandatory calibration – Safety protection: 1. Pressure gauges used for safety protection must undergo mandatory calibration. Including the following 7 categories: 1.1 Measurements of the boiler’s main cylinder and feedwater pressure areas ； 1.2 Measurement of the pressure in the air receiver and main ducts of fixed air compressors ； 1.3 Measurement of generator and turbine oil pressure as well as locomotive pressure ； 1.4 Measurement of pressure in medical autoclaves and pressure cookers ； 1.5 Pressure measurement with alarm device ； 1.6 Measurement of pressure in sealed pressurized vessels ； 1.7 Measurement of pressure in hazardous, toxic, and highly corrosive media. (For example: Bourdon tube pressure gauges, electric remote transmission pressure gauges, and electric contact pressure gauges) 2. Pressure gauges used for safety protection must undergo mandatory calibration. That is: the measurement of wind pressure and wind speed in the tunnels of a mine. (e.g.: mine air pressure gauges, mine wind speed meters). 3. Oxygen meters used for safety protection must undergo mandatory calibration. Including the following 2 categories: 3.1 Measurement of oxygen monitoring pressure during oxygen cylinder filling ；    3.2 Measurement of oxygen pressure, which is explosive and poses a safety risk during the process.

I’ve learned something, thanks for sharing

Pressure transmitters are no longer on the list of devices subject to mandatory inspection

What was said on the 2nd floor is correct; the measurement standard should also be that, right?