Safety inspection of refrigeration systems: Standards and implementation procedures

Why is refrigeration system inspection required? Legal basis and operational benefits

Implementation refrigeration system inspection is a mandatory legal requirement from the State authorities to ensure absolute operating safety throughout the equipment's service life. Businesses should pay particular attention to these three legal instruments:

• Law on Occupational Safety and Hygiene 2015 (Article 30, Clause 4): requires every machine and item of equipment with strict occupational safety requirements to undergo technical safety inspection before being put into actual operation.
• Decree 44/2016/ND-CP: sets out in detail the operating conditions for occupational safety inspection organisations.
• Circular 36/2019/TT-BLDTBXH: issues the list of equipment with strict requirements, which includes pressure vessels, chiller systems and industrial refrigeration compressors.

A business that fails to carry out refrigeration system inspection on time faces administrative penalties under Decree 12/2022/ND-CP, and may even have operations suspended when the authorities inspect.

Beyond legal compliance, periodic inspection brings practical value to plant operations:

• Early detection of latent risks: the inspection identifies common faults such as a safety relief valve seized with rust, vibrating pipework cracking welds, or measuring instruments reading inaccurately. This matters especially for complex systems such as IQF quick-freezing conveyors.
• Optimised equipment performance: a system inspected and serviced on schedule can save 10% to 15% of electricity compared with equipment running past its due date.
• Preventing refrigerant leaks: Job refrigeration system inspection helps find small gas leaks early, reducing the cost of topping up refrigerant and protecting the environment.
• Completing insurance documentation: the inspection certificate is a mandatory document for a business to claim property insurance benefits when an incident occurs.

At Tan Long, with specialists of more than 20 years' experience, we commit to helping customers complete every technical procedure to meet the most demanding safety inspection standards. If you are planning an upgrade or a new installation, look at our refrigeration system design and installation service to ensure consistency and safety from the outset.

Mandatory refrigeration inspection standards in Vietnam

Carrying out refrigeration system inspection must strictly follow the national technical regulations and safety standards approved by the authorities. Where a business chooses to apply international standards to its system, the minimum technical requirements must not fall below the current domestic regulations.

Below is the list of key legal instruments and technical standards applied in refrigeration system inspection in Vietnam:

At Tan Long, every project from the consultation cold storage design stage through to equipment installation is checked carefully against the standards listed above. This compliance not only makes it easy for customers to complete the refrigeration system inspection procedures but also ensures that equipment such as evaporative condenser and the compressor operate durably, avoiding legal and technical risk.

To keep the system to standard before the authorities inspect, businesses should coordinate inspection closely with a scheduled industrial refrigeration maintenance programme.

Conditions to be met before refrigeration system inspection

For the refrigeration system inspection process to run smoothly, accurately and in line with Ministry of Labour requirements, the business needs to prepare the following four prerequisites carefully:

• The system ready for technical operation: the whole system, including core equipment such as the industrial refrigeration compressor and heat exchangers, must be fully charged with refrigerant and supplied with stable power. The system must be ready to start immediately so the inspector can check actual operation and measure pressure and current..
• Complete technical documentation assembled: the business needs a documentation set ready comprising: the equipment data record from the manufacturer, the refrigeration system design and installation drawings, conformity certificates refrigeration system inspection.
• Favourable working conditions: detailed pressure and temperature measurements require stable environmental conditions. Extreme weather, or a machine area with excessive temperature or humidity, directly affects the measurement error. The space around the equipment must therefore be well ventilated and dry before the inspector begins work.
• Strict compliance with occupational safety and hygiene: the area where refrigeration system inspection is carried out must be cordoned off with barriers or warning signs. The business should assign technical staff familiar with the system to assist, and provide full personal protective equipment (PPE) for the inspection and supervision team. This matters especially when working with NH3 systems or large-capacity IQF freezers of large capacity.

Preparing these steps well not only shortens the procedure but also gives the business a chance to review the effectiveness of its refrigeration system maintenanceprogramme, keeping the plant operating safely and at high efficiency.

The refrigeration inspection procedure under Circular 36/2019/TT-BLDTBXH

The technical safety inspection procedure for refrigeration systems comprises 6 steps carried out in a mandatory order. The next step proceeds only when the previous one has passed.

Step 1: Check technical documents

The inspector reviews all documentation supplied by the business, including the equipment data record, technical drawings, design specifications, conformity certificates and the operating and maintenance log. The purpose is to confirm the system was installed to the design, has no unapproved structural changes, and that the documentation reflects the actual condition.

Step 2: General technical inspection, external and internal

The inspector carries out two forms of examination in parallel:

• Visual examination: observing metal surfaces for corrosion, flaking and geometric deformation; checking the condition of the insulation and cladding; and assessing stairs, working platforms and access conditions.
• Non-destructive testing (NDT): using ultrasonic (UT), radiographic (RT), dye penetrant (PT) or magnetic particle (MT) methods to find hidden defects inside the base metal, the refrigerant pipework and the welds. This is

Step 3: Pressure testing

The pressure equipment and pipework are isolated for two types of test:

• Pressure test: raising the pressure to the specified level (usually 1.25-1.5 times the maximum allowable working pressure) and holding it for a set time to verify load-bearing capability.
• Leak test: checking the tightness of the whole system at the allowable working pressure for a minimum of 24 hours, to find small refrigerant leaks that cannot be seen by eye.

Step 4: Check safety mechanisms and measuring equipment

The safety relief valve, high/low pressure switches, thermometers, pressure gauges and the entire automatic protection system are function-tested. Measuring instruments must be calibrated periodically and still in date. This is the step that uncovers the most faults, particularly safety valves seized with rust from long periods without activation.

Step 5: Checking actual operation

The system is started and run in normal mode. The inspector monitors temperature, suction pressure, discharge pressure, compressor current and other operating parameters under real load. This step confirms the system achieves its design cooling capacity

Step 6: Processing results and issuing certification

After compiling the results of the 5 steps above, there are two outcomes:

• Pass: the inspector prepares the inspection report, affixes the inspection sticker to the equipment, seals the safety devices and issues an inspection certificate valid nationwide, usually within 3-5 working days.
• Fail: a detailed remediation report is issued, specifying the location of each fault, its severity and the remedy. The business rectifies the faults before re-inspection takes place.

Documentation to prepare for refrigeration system inspection

Preparing complete legal and technical documentation is the key step in shortening the time spent with the authorities. Depending on the project's operating stage, the refrigeration system inspection documentation set will comprise the following specific groups:

First inspection (carried out after installation and before use)

This is the most important stage for confirming the system was installed to technical safety standards. The required documents are:

• Equipment and pressure vessel data records: the original documentation issued by the manufacturer for the equipment in the system.
• Construction design drawings: including the project's detailed P&ID process and piping diagram.
• Equipment conformity certificates: applying to high-pressure components such as pressure vessel, the high-pressure receiver or the oil separator.
• Technical calculation records: documents demonstrating the design capability of the cold storage design consultant.
• Installation acceptance report: the document confirming completion of installation between the investor and the contractor.
• Instrument calibration certificates: valid calibration certificates for the pressure gauges and measuring instruments in the system.

Periodic inspection (re-inspection during operation)

This activity keeps the system continuously safe after a period of operation. The business needs to provide:

• Original documentation: the originals or notarised copies of the entire first inspection documentation set.
• The immediately preceding inspection report: the result of the most recent refrigeration system inspection that is still valid or has just expired.
• Operating and maintenance log: detailed records of the operating history and each round of industrial refrigeration system maintenance from the previous inspection to now
• Repair and modification records: reports of equipment replacements or major repairs during the operating period, if any.

Keeping complete, accurate documentation serves not only the refrigeration system inspection process but also as evidence of the business's operational management capability to major partners. Tan Long always helps customers review their technical documentation on every project it supplies refrigeration system design and installation to make the inspection process as smooth as possible.

Refrigeration system inspection intervals

Complying with refrigeration system inspection intervals is mandatory to ensure operating safety and meet the legal requirements on occupational safety. Depending on the condition and technical characteristics of each project, the inspection timing is divided as follows:

First inspection

This must be carried out immediately after refrigeration system installation is complete and before the system is formally put into operation. Under the regulations, no industrial refrigeration system may operate without a valid first inspection certificate.

Periodic inspection

The periodic inspection interval depends on the refrigerant used and the age of the equipment, particularly the refrigeration compressor units and pressure vessels.

Note: if the equipment manufacturer specifies a shorter interval than the table above, the business must follow the manufacturer's instructions. The inspector will state the reason for the shortened interval in the actual inspection report.

Extraordinary inspection

An extraordinary refrigeration system inspection is carried out outside the periodic cycle in the following special cases:

• at the direct request of the labour inspectorate, or when a technical incident needs investigating.
• after the business relocates or changes the installation position of core equipment.
• after major repairs or replacement of important pressure-bearing parts such as vessels or main pipework, or a change of compressor model during refrigeration system maintenance.
• after the system has been out of operation continuously for more than 12 months and needs restarting for production.

Tracking inspection due dates proactively not only helps a business avoid legal risk but also keeps complex systems such as IQF freezing conveyors and large-scale cold stores at optimal performance.

Reference costs for refrigeration system inspection

The minimum cost framework for refrigeration system inspection is set in Circular 41/2016/TT-BLDTBXH. The actual level depends on system capacity, the number of pressure vessels, the refrigerant type, the location and the inspection organisation chosen.

Factors raising the cost above the base level include: a large number of pressure vessels, requirements for in-depth NDT (radiographic examination), long travel distances, and requests for rapid completion outside office hours.

Contact Tan Long's technical team on the hotline 0933 357 058 for advice, an introduction to a suitable inspection organisation, and free help preparing the documentation.

Organisations authorised to inspect refrigeration systems

Only organisations issued a certificate of eligibility for technical safety inspection by the Department of Occupational Safety, Ministry of Labour, have the authority to carry out refrigeration system inspections and issue legally valid certificates.

A business should check whether the inspection organisation is on the Department of Occupational Safety's designated list before signing a contract. A certificate issued by a non-designated organisation has no

Tan Long can connect businesses with designated inspection bodies and help assemble complete technical documentation from the installation stage, so the inspection goes as smoothly as possible.

Refrigeration system inspection is a mandatory legal obligation and the most effective way to protect both assets and people throughout the equipment's operating life. The 6-step procedure under Circular 36/2019/TT-BLDTBXH comprises documentation review, general technical inspection, pressure testing, safety device inspection, operational checking and processing the results.

Inspection intervals run from 1 to 3 years depending on equipment age and refrigerant type. Businesses should prepare complete technical documentation in advance and choose an inspection organisation designated by the Department of Occupational Safety so the certificate carries legal validity.

For advice and help preparing refrigeration system inspection documentation, call the free hotline 0933 357 058 or fill in the contact form and Tan Long's technical team will respond within 2 working hours.

Frequently asked questions about refrigeration system inspection

Do small refrigeration systems under 20 kW need inspection?

Yes. The law applies by equipment type, not by capacity. Any refrigeration system containing pressure equipment (receivers, separators) falls within the mandatory inspection list under Circular 36/2019/TT-BLDTBXH.

What has to be done if a system fails inspection?

The inspector issues a report specifying the items that failed and the remediation required. The business carries out the repairs per the report, then registers for re-inspection. The system may not operate until the remediation is complete.

Is there a penalty if the inspection certificate expires?

Yes. Under Decree 12/2022/ND-CP, using equipment with strict occupational safety requirements without a valid inspection certificate carries a fine of 5,000,000 to 10,000,000 VND and a mandatory halt to use of the equipment until inspection is completed.

Are chiller systems and central air conditioning systems subject to inspection?

Yes. Circular 36/2019/TT-BLDTBXH explicitly lists refrigeration systems, chiller systems and central air conditioning systems as subject to mandatory technical safety inspection.

How long does one inspection take to complete?

On-site inspection usually takes 1 to 3 working days depending on system scale. The inspection body then needs a further 3 to 5 working days to process the documentation and issue the certificate.