Circular No. 57/2025/TT-BCT stipulates certain technical contents in oil and gas activities

CIRCULAR

REGULATIONS ON CERTAIN TECHNICAL CONTENTS IN OIL AND GAS ACTIVITIES

__________________

THE MINISTER OF INDUSTRY AND TRADE

Pursuant to the Oil and Gas Law dated November 14, 2022;

Pursuant to Decree No. 45/2023/NĐ-CP dated July 1, 2023 of the Government detailing certain provisions of the Oil and Gas Law;

Pursuant to Decree No. 40/2025/NĐ-CP dated February 26, 2025 of the Government stipulating the functions, tasks, powers, and organizational structure of the Ministry of Industry and Trade;

At the proposal of the Director of the Department of Oil and Gas and Coal,

The Minister of Industry and Trade issues this Circular regulating certain technical contents in oil and gas activities.

PART I

GENERAL PROVISIONS

Article 1. Scope of Application and Scope of Regulation

1. This Circular regulates certain technical contents related to exploration, development, and exploitation of oil and gas within the territory, islands, and maritime areas of the Socialist Republic of Vietnam.

2. This Circular applies to agencies, organizations, and individuals, both domestic and foreign, involved in oil and gas activities in Vietnam.

Article 2. Definitions

In this Circular, the following terms shall be understood as follows:

    1. Oil and gas production facilitymeans an oil and gas facility serving the exploitation of oil and gas.

    2. Casing completion intervalis the section of the wellbore that has been reinforced or equipped with equipment through which fluid flows into or out of the wellbore.

    3. Annulus space for exploitationis the space between the outer wall of the oil production casing and the inner wall of the oil protection casing.

    4. Rock sampleincludes core samples, sidewall samples, cuttings, and drill cuttings collected during drilling operations.

5. Auxiliary meansinclude transportation means such as air, water, land, or other means used to transport people, materials, and equipment or to assist in other works.Product reservoir

    6. is a natural oil and gas reservoir separated from other reservoirs by barriers.Article 3. Naming of Reservoirs, Product Layers, Structures, Oil Fields, and Drilling Wells

1. The names of reservoirs, product layers, structures, oil fields, and drilling wells are assigned by the operator and must be consistent with the regulations of the law, not violate historical traditions, cultural values, ethics, and customs of the nation, and not use sensitive or misleading terms.

2. The names of reservoirs, product layers, structures, oil fields, and drilling wells must be used in all reports, records, and related documents.

3. The name of a drilling well consists of the following parts separated by a hyphen in the following sequence:

a) The name of the oil block;

b) The abbreviated name of the structure or oil field;

c) The name of the well including the well number and type code defined as follows:

Exploration wells are marked with the letter X;

Injection wells are marked with the letter I;

Production wells are marked with the letter P;

Sidetrack wells are marked with the letters ST;

Wells with multiple purposes are marked with corresponding letters;

Other well names (if any) will be determined by the operator and the Vietnam National Industrial and Energy Group.

OIL AND GAS EXPLORATION ACTIVITIES

Chapter II

Article 4. General Provisions on Conducting Oil and Gas Exploration

1. The main contents of oil and gas exploration activities include:

a) Identifying and ranking potential plays, structures, traps, and reservoirs;

b) Determining and evaluating geological characteristics, oil and gas systems, permeability and storage properties, fluid characteristics, and commercial viability of reservoirs and oil-bearing formations;

c) Evaluating the potential and risks of discovered and undiscovered reservoirs, and developing exploration and appraisal plans;

d) Assessing oil and gas resources, reserves, and the scale of structures, prospects, discoveries, and fields, and identifying risk factors to develop exploration and appraisal plans and prepare resource and reserve reports.

2. The main steps in conducting oil and gas exploration include:

a) Collecting, analyzing, and evaluating geological, geophysical data, and information related to geological conditions and resource potential;

b) Implementing a combination of surveying, seismic, gravity, magnetic, remote sensing, and oil and gas resource evaluation works, including processing and interpreting geophysical data, determining well locations, and designing exploration and appraisal wells;

c) Pre-drilling assessment, including potential structure research reports, geological well drilling plans, and drilling programs;

d) Drilling exploration and appraisal wells;

e) Post-drilling assessment, including geological completion reports, well construction activity summary reports, and post-drilling evaluation research reports.

3. After completing drilling operations, the operator is responsible for updating relevant information, studies, and assessments, finalizing, and submitting geological completion reports in accordance with the oil and gas contract or agreements with the Vietnam National Industrial and Energy Group (if applicable).

Article 5. Geophysical Survey

1. The main contents of the plan for implementing geophysical surveys include:

a) Survey methods and objectives;

b) Implementation methods for geophysical surveys;

c) Safety and environmental management during geophysical surveys;

d) Plan for submission of geophysical survey data before and after implementation.

2. When conducting geophysical surveys, organizations and individuals are responsible for:

    2. When conducting geophysical surveys, organizations and individuals shall be responsible for:

a) Arrange necessary signs and directions, and notify vehicles operating in the implementation area;

b) Conduct geophysical surveys according to approved plans, areas, regions, and networks;

c) Comply with other relevant legal regulations.

After completing the geophysical survey, the operator shall report and submit the results of the geophysical survey collected during the implementation period, in accordance with the oil and gas contract or agreement with the Vietnam National Oil and Gas Group (if applicable).

Article 6. Drilling Wells

1. The main contents of the drilling program include:

a) General information about the well including:

- Well name, well coordinates, sea water depth, height above sea level; drilling rig construction site; construction time; well structure; drilling fluid; drill string, drill bit, and hydraulic system; directional drilling (if any); casing; cementing pump for the well; wellhead system and blowout prevention equipment;

- Information on geological engineering survey results of the platform placement area, seabed survey;

- Plan for testing blowout prevention equipment, wellhead, casing, and fracture pressure;

b) Geological objects of the well, well temperature and pressure conditions, geophysical logging program, sampling, and formation testing (if any);

c) Preparation work for drilling operations including: positioning the drilling rig, preparation before drilling starts;

d) Drilling procedures for each stage according to the designed well depth;

đ) Completion plan for the well; preliminary well completion plan (if any);

e) Risk prediction and risk mitigation measures during drilling.

2. Prior to conducting well drilling and related activities, organizations and individuals responsible must develop safety management documents in accordance with Articles 39 and 40 of Decree No. 45/2023/NĐ-CP dated July 1, 2023, of the Government detailing certain provisions of the Petroleum Law (hereinafter referred to as Decree No. 45/2023/NĐ-CP).

3. During well drilling operations, organizations and individuals responsible must:

a) Drill according to the program, plan, design, or approved adjustments;

b) Implement emergency response and environmental protection measures during drilling.

c) Comply with other relevant legal regulations.

Article 7. Final Report on Well Construction Activities

1. The operator is responsible for submitting a final report on well construction activities to the Vietnam National Oil and Gas Group within sixty working days after completing the drilling program.

2. The final report on well construction activities includes the following main contents: general information about the well; evaluation of well drilling performance compared to the planned program; well completion work and actual status diagram of the well after completion; preliminary geological oil and gas results (if any) and data obtained from the last survey regarding surface conditions and surrounding areas of the well.

Chapter III

ACTIVITIES FOR DEVELOPING OIL AND GAS FIELDS AND PRODUCTION

Article 8. Putting Oil and Gas Production Facilities into Operation

1. Oil and gas production facilities must be inspected and accepted before being put into operation and use in accordance with the provisions of the oil and gas contract and agreements signed between the parties in compliance with the law.

2. For oil and gas production facilities located in port waters or shipping channels, prior to putting the facility into operation and use, the operator must establish a safe zone around the oil and gas production facility in accordance with Clause 1 and Clause 2 of Article 8 of the Petroleum Law and maritime laws. This safe zone must be indicated and warned in accordance with maritime laws.

Article 9. Support Vessels and Field Service Vessels

1. Support vessels must be designed, manufactured, operated, and maintained to ensure safe operation under forecasted natural environmental conditions in the operational area in accordance with the law and international treaties to which Vietnam is a party.

2. Field service vessels must meet technical standards as prescribed and ensure the following conditions:

a) Have sufficient temporary shelter for personnel present at the oil and gas production facility in case of evacuation;

b) Be equipped with first aid equipment and personnel capable of providing first aid to injured persons;

c) Have the capability to rescue people who fall into the sea near the oil and gas production facility;

d) Be equipped to operate as a communication center in emergencies to ensure communication between the oil and gas production facility and other ships and nearby oil and gas facilities, with rescue vessels, bases, and land-based rescue facilities.

3. Offshore oil and gas production facilities where personnel reside or work regularly must have field service vessels ready to assist in rescuing personnel on the oil and gas production facility in emergencies and to access the facility if deemed necessary for rescue purposes in the following situations:

a) Helicopter takeoff or landing;

b) Personnel outside the side of the vessel;

c) Personnel near the water's edge or underwater;

d) Warning to avoid the risk of collision, impact, and other dangers to the oil and gas production facility.

4. Offshore oil and gas production facilities designed without personnel residing there must have appropriate support vessels available in case of occasional personnel presence or work to be ready to assist in emergencies.

Article 10. Wellbore Safety Valves

1. For offshore producing wells, the wellbore safety valve must be installed at a minimum depth of 30 meters below the seabed in the following cases:

a) A well that has the ability to flow naturally without mechanical support and a well with a fluid production volume at opening greater than the allowable leakage rate for the wellbore safety valve according to the latest version of the API RP 14B recommendation (Design, Installation, Operation, Testing, and Maintenance of Wellbore Safety Valve Systems);

b) A well producing gas with a hydrogen sulfide (H2S) content higher than 50 ppm volume.

2. For onshore wells capable of flowing naturally without mechanical support, the wellbore safety valve must be installed in the following cases:

a) The well is located within a range that may pose danger to residents, the environment, and well equipment due to blowout or oil spill incidents;

b) A well producing gas with a hydrogen sulfide (H2S) content higher than 50 ppm volume.

3. Technical specifications, design, installation, operation, maintenance, repair, and replacement of the wellbore safety valve must comply with the API Spec 14A standard (Technical Characteristics of Wellbore Safety Valve Equipment) and the latest version of the API RP 14B recommendation (Design, Installation, Operation, Testing, and Maintenance of Wellbore Safety Valve Systems) or other standards consistent with international oil and gas industry practices.

4. All installed wellbore safety valves must be:

a) Pressure tested immediately after installation;

b) Inspected at least once a year; or more frequently if required by actual field operations.

5. The operator is only permitted to operate the well when the wellbore safety valve can function normally or when other safety measures are in place.

6. The operator is responsible for implementing all necessary measures to ensure the safety of the well.

Article 11. Wellhead Equipment, Tubing, and Emergency Shut-off Valves

1. The operator must install emergency shut-off valves at the wellhead and tubing in the following cases:

a) Wells producing products containing hydrogen sulfide (H2S) with a concentration exceeding 50 ppm volume;

b) Wells in offshore production areas;

c) When it is necessary to isolate the well from the flowline or injection line due to an incident that could cause harm to people or severe damage to the natural environment.

2. Wellhead equipment and tubing are designed and installed with pressure measuring devices between the production casing and the intermediate casing, as well as between the intermediate casings.

3. After initial installation and each repair, the tubing is tested for its maximum operating pressure.

4. Emergency shut-off valves must be regularly maintained, serviced, and inspected at least once a year according to the latest version of the API RP 14H recommendation (Installation, Maintenance, and Repair of Surface and Subsea Well Control Equipment) or other standards consistent with international oil and gas industry practices.

Article 12. Measurement and Survey of Well Parameters and Oil and Gas Reservoirs

1. The operator conducts measurements and surveys of wells to collect reservoir parameters, formation conditions, well status, and production and injection equipment before and during production and annually thereafter.

2. Measuring and surveying equipment must be calibrated or verified in accordance with legal metrology regulations.

3. In cases where the scheduled measurement and survey schedule specified in Clause 1 of this Article needs to be adjusted to suit actual oil and gas production conditions, the operator shall notify and coordinate with the Vietnam National Industry and Energy Corporation.

4. The operator is responsible for storing and sharing survey information and data upon request from the Vietnam National Industry and Energy Corporation, and submitting collected information and parameters to the Vietnam National Industry and Energy Corporation after completion of work.

Article 13. Sampling and Analysis of Fluid Samples and Rock Samples

1. For fluid samples:

a) The operator collects bottom fluid samples or surface fluid samples or both to recreate the original reservoir conditions at wells undergoing reservoir testing or production;

b) During production, the operator collects sufficient fluid samples at appropriate wellheads annually or as needed to analyze the composition of oil, gas, and water in the reservoir, in accordance with the latest version of the API RP 44 recommendation (Sampling of Oil and Gas Reservoir Fluids) or other standards consistent with international oil and gas industry practices;

c) When water appears in the fluid from a well that has been put into production, the operator takes and analyzes water samples to determine the composition of produced water and assess the source of the produced water within technological limits;

d) Water samples taken as described above are analyzed in accordance with the latest version of the API RP 45 recommendation (Analysis of Produced Water from Oil and Gas Wells) or other standards consistent with international oil and gas industry practices;

e) The operator submits to the Vietnam National Industry and Energy Corporation the results of the analysis of the fluid composition from the reservoir or production zone, descriptions of the basic physical and chemical properties of the fluids, or other information requested by the Vietnam National Industry and Energy Corporation upon completion of the analysis and when full reports are available.

2. For rock samples:

a) Collect rock samples according to the sampling plan, preserve them, and conduct analyses to provide complete geological data and parameters for evaluating the reservoir;

b) Store and submit the results of rock sample analysis as prescribed.

Article 14. Completion and Operation of Wells

1. The operator completes and operates oil and gas wells in accordance with technical standards and procedures to ensure safe well operation, environmental protection, continuous monitoring and control of all well activities, and efficient recovery of oil and gas.

    2. The operator shall immediately adjust the equipment of the well or change the completion interval of the well to ensure the oil and gas recovery factor. In cases where technical conditions do not allow such work to be carried out, the operator shall notify the Vietnam National Industry and Energy Group and clearly state the reasons.

    3. For wells that simultaneously exploit multiple layers designed to be separately completed, the operator shall perform the following tasks:

    a) After completing the well, the operator shall conduct separate tests on each layer to ensure that the separation between the layers is good, both inside and outside the casing;

    b) During subsequent exploitation, if there is any doubt about this separation, the operator shall immediately carry out separate testing activities.

    4. After completing the activities prescribed in Clauses 1, 2, and 3 of this Article, the operator shall submit a report on the well completion and operation activities to the Vietnam National Industry and Energy Group, including the following contents:

    a) Summary of activities and incidents occurred (if any);

    b) Diagrams and technical parameters of the equipment in the wellbore, casing, production tubing, surface tree, and production control system;

    c) Parameters regarding the composition and properties of the fluid used for well completion;

    d) Evaluation of the results of the works performed.

    Article 15. Production Annulus

    1. The operator shall not put offshore wells, onshore gas wells with hydrogen sulfide (H2S) content exceeding 50 ppm volume into exploitation operation when the production annulus is not effectively separated from the completion interval of the well.

    2. The production annulus shall be constructed and installed so that it can easily release pressure.

    3. The operator shall select the least harmful fluid for well completion or repair operations suitable for international petroleum industry practices.

    4. The operator shall install packers for wells required to be equipped with downhole safety valves according to Article 10 of this Circular. In special technological cases where it is not necessary to install packers, the operator shall coordinate with the Vietnam National Industry and Energy Group on safety assurance principles and compliance with international petroleum industry practices.

    Article 16. Inspection of Valves and Pressure Sensors for Onshore Oil and Gas Facilities

    1. For onshore oil and gas facilities, the operator shall perform the following tasks:

    a) Inspect all emergency shut-off valve systems at the wellhead at least once every six months;

    b) Inspect safety valves installed at the well or onshore oil and gas facility at least once a year;

    c) Inspect pressure sensors at least once every three months;

    d) Inspect liquid level control devices by activating the sensors at least once every three months;

    đ) Inspect automatic shut-off valves connected to air compressors or at the inlet of pressure vessels, test the automatic shut-off valves operating according to the lowest closure principle on pipelines at least once every three months;

    e) When onshore oil and gas facilities are equipped with gas processing or oil equipment, the operator shall inspect all safety valves of such equipment at least once a year.

    2. When inspecting equipment as prescribed in Clause 1 of this Article and discovering damage or inaccuracy, the operator must immediately replace or calibrate the equipment in accordance with the legal provisions on measurement.

    Article 17. Relief Systems

    1. At oil and gas exploitation facilities, the operator shall connect relief valves and hydrocarbon liquid treatment equipment to separators or storage tanks with sufficient capacity to contain the largest possible volume of liquid before the system is safely closed.

    2. At oil and gas exploitation facilities, all relief valves on gas processing equipment must be connected to a flare system or gas venting system.

    3. For oil and gas exploitation facilities with hydrogen sulfide (H2S) content in the produced fluids, the operator must ensure that the H2S (hydrogen sulfide) content in the air in the exploitation facility area complies with the national technical regulation QCVN 03:2019/BYT dated June 10, 2019 on permissible exposure limits for 50 chemical factors in the workplace.

    Article 18. Flaring, Venting Gas, and Burning, Disposing of Oil

    1. Flaring, Venting Gas:

    The operator may only flare or vent gas in accordance with Clause 2 of Article 49 of the Petroleum Law, ensuring the following requirements:

    a) The flow rate or volume of flared or vented gas does not exceed the amount necessary to clean and clear the well;

    b) Flaring gas for testing purposes or after well completion, repair, or treatment if expected to last more than 48 hours must be coordinated with the Vietnam National Industry and Energy Group by the operator;

    c) Periodic flaring of excess gas from the technology system that cannot be collected and flaring that does not pose a safety risk; flaring in emergencies such as compressor or other equipment failure; flaring during regular maintenance, inspection, and testing;

    d) In emergencies, the operator may temporarily vent gas (without flaring) through safety valves for up to 24 hours. If venting exceeds 24 hours, it must be coordinated with the Vietnam National Industry and Energy Group by the operator.

    2. Burning, Disposing of Oil:

a) The operator shall carry out oil burning or disposal in emergency situations or when they consider it necessary to burn or dispose of oil during well completion or repair work, or in the case of stimulation to increase flow rate, provided that the volume of oil burned or disposed of is less than 01 m3/h and must ensure environmental safety in accordance with the provisions of the law.

b) The operator must immediately notify the Vietnam National Oil and Gas Group in writing when burning or disposing of oil and must have emergency response plans ready.

c) During well testing, the operator may only burn or dispose of oil in quantities agreed upon by the Vietnam National Oil and Gas Group.

3. After ceasing oil burning, gas venting, and oil disposal as stipulated in Clause 1 and Clause 2 of this Article, the operator shall submit a report on the actual amount of oil burned, gas vented, and oil disposed of to the Vietnam National Oil and Gas Group.

Article 19. Management of Oil and Gas Fields and Other Activities Concurrently with Production Operations

1. Extraction methods, extraction targets, well networks, and well operations shall be carried out in accordance with approved contents and international petroleum industry practices.

2. The operator shall conduct pressure maintenance injection in accordance with the approved target, reservoir, and injection network.

3. During production, if abnormal reservoir pressure decline occurs which poses a risk of affecting the final oil and gas recovery factor of the field, the operator shall conduct research, address the issue, and report to the Vietnam National Oil and Gas Group to promptly adjust the production volume to ensure safe field operation.

Article 20. Monitoring, Measurement, and Recording of Environmental Parameters

1. For onshore oil and gas facilities, the operator shall organize environmental monitoring in accordance with environmental protection laws.

2. For onshore oil and gas facilities, the operator shall observe and record wind direction, wind speed, temperature, and rainfall according to a set schedule.

3. For offshore oil and gas facilities with personnel operating them, the operator shall be responsible for:

a) Maintaining comprehensive records of natural environment observations during each day's field operation.

b) Recording weather forecasts for each day and noting changes in weather conditions from the forecast during production activities.

c) Floating or semi-submersible production platforms shall be observed and recorded for inclination, heave, pitch, and roll of the production system and tension of each mooring line at least once every six hours when wind speed is below 35 km/h and at least once every three hours when wind speed exceeds 35 km/h.

4. The operator may refer to and utilize monitoring and measurement data from other offshore oil and gas facilities within the same field or adjacent fields.

Article 21. Suspension of Oil and Gas Production Activities

1. The operator must immediately cease oil and gas production activities in the following cases:

a) Production activities cause serious accidents or incidents, or continuing such activities will seriously endanger the safety of workers, oil and gas facilities, or violate waste management and environmental protection regulations.

b) There is a serious injury where stopping production would prevent further serious consequences or an incident posing danger to people and severe damage to equipment.

c) Unforeseen events such as natural disasters or war occur.

d) It involves national security as directed by competent authorities.

2. When a well in the production area loses control or there is a risk of losing control, the operator must shut down all wells in that production area until the risks are mitigated.

3. When suspending production activities, the operator has the responsibility to immediately report to the Vietnam National Oil and Gas Group. The operator may resume production activities only after completing adjustments and repairs that meet legal requirements for safety and environmental protection.

Chapter IV

IMPLEMENTING PROVISIONS

Article 22. Effectiveness and Implementation

    1. This Circular shall take effect from January 20, 2026.

    2. In cases where the normative legal documents or technical standards cited in this Circular are amended, supplemented, or replaced, implementation shall be carried out according to the provisions of the new document.

    3. During the implementation process, if there are difficulties or obstacles, organizations, individuals, and the National Industry-Energy Corporation of Vietnam shall report to the Ministry of Industry and Trade for consideration and resolution within their authority.