Authorization for the highest-level measurement standards in enterprises

Article 1 specifies the \"scope of measuring instruments not subject to mandatory verification and the determination of their verification intervals.\" Article 2 clarifies the \"verification methods for measuring instruments not subject to mandatory verification,\" which may involve self-verification or sending them for verification. Article 3 specifies the scope of measuring instruments subject to mandatory verification, which includes the enterprise’s highest-level measuring standards. When an enterprise establishes standard devices for measuring instruments that are not subject to mandatory verification within its own premises, it must consult with the metrology department of the local quality and technical supervision bureau. Upon reaching an agreement, the enterprise may apply to the competent technical supervision authority for the establishment of such standards and for standard evaluation; only after passing this evaluation can verification activities be carried out within the specified scope.

First, the instrument technicians must possess certification as metrology verifiers for the internal inspection items required; at least two people are needed for each item. Next, a standard room should be established and metrological standards purchased. Finally, the Technical Supervision and Administration Bureau must conduct an inspection and grant authorization.

Management practices vary from place to place; do the three major oil companies, along with local refining and petrochemical companies, all have their own standardization, inspection, and metrology departments? Not necessarily... If standards are established, there’s no need for external inspections at all. SH/T 3521-2013 Technical Specifications for the Construction of Petrochemical Instrumentation Projects > 5 Calibration and Adjustment of Instruments > 5.1 General Provisions 5.1.1 These specifications apply to the inspection of process control and testing instruments in the petrochemical industry; they are not applicable to the verification of instruments that constitute the highest level of measurement standards as stipulated by the Metrology Law of the People’s Republic of China, nor to instruments used for trade settlement, safety protection, environmental monitoring, etc ； Meters and instruments included in the list of instruments subject to mandatory verification. 5.1.2 Before installation and commissioning, the instruments shall be inspected, calibrated, and tested to ensure that they meet the requirements of the design documents as well as the technical specifications specified in the product’s technical documentation. 5.1.3 Calibration and testing of instruments prior to installation shall be carried out indoors. The calibration room should meet the following conditions: a) The interior should be clean, quiet, well-lit, well-ventilated, and free from vibrations as well as strong electromagnetic field interference ； b) The indoor temperature should be maintained between 10~35°C, with a relative humidity of no more than 85% ； c) It has water supply and drainage facilities. 5.1.4 The supply voltage for instrument testing should be stable. An AC voltage stabilizer should be installed; the voltage fluctuations of the AC power supply and DC power supplies above 60V should not exceed ±10%, while those of DC power supplies below 60V should not exceed ±5%. 5.1.5 The air source used for instrument testing should be clean and dry, and the air pressure should be stable. 5.1.6 Instrument calibrators must hold valid qualification certificates: Before calibration, they should be familiar with the instrument specifications outlined in the technical documents and design files related to the instruments, and they must have the necessary standard instruments and tools for calibration available. 5.1.12 After the instrument has passed calibration, a calibration record should be filled out promptly. The data must be accurate and the handwriting clear; it shall be signed by the person who performed the calibration, the quality inspector, and the technical supervisor. The calibration date should also be indicated, and a certification label indicating successful calibration (with the instrument’s identification number) should be attached to the instrument. My understanding and perception of the above petrochemical standards (which are excerpted from the national standard GB 50093-2013, Code for Construction and Quality Acceptance of Automation Instrumentation Projects) is as follows: 1. Instruments that are subject to mandatory inspection must be sent for testing on a regular basis (in most cases, this service is provided free of charge; it’s only right to do so). 2. Periodic self-check of non-mandatory inspection instruments (Class B). 3. There should be a gauge calibration laboratory that looks properly organized. 4. The person involved in measurement (i.e., the one who issues the certificate of conformity) should have a verifier’s certificate. 5. Measuring instruments, such as standard gauges, are sent for inspection, and a traceability diagram of the measured values can be created. 6. For measuring instruments, such as calibration tables, have the manufacturer issue a certificate of conformity on a regular basis to give peace of mind; of course, if they do break down, remember to send them back to the factory for repair.

1. For calibration and standard establishment, it is possible to apply for the calibration and standard setting of pressure gauges. For detailed procedures, consult the local Quality and Technical Supervision Bureau, the Market Regulation Bureau, or the Administrative Approval Bureau (the names of these agencies vary from place to place). Once standards have been established, it becomes possible to calibrate equipment that is not subject to mandatory calibration； 2. Certification authorization: On the basis of establishing standards, an application can be submitted for authorization to conduct mandatory inspections (the two applications can be submitted simultaneously); once authorized, it is possible to inspect equipment subject to mandatory inspection

The person involved in measurement (i.e., the one who issues the certificate of conformity) should have a certifier’s certificate: the requirement for such a certificate no longer exists; it has been abolished. However, proof of the ability to carry out the relevant work is required, such as a certificate of completion of internal company training.

The person involved in measurement (i.e., the one who issues the certificate of conformity) should have a certifier’s certificate: the requirement for such a certificate no longer exists; it has been abolished. However, proof of the ability to carry out the relevant work is required, such as a certificate of completion of internal company training.