GB/T 8927-2008 Petroleum and liquid petroleum products — Temperature measurement — Manual method

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1. Method number / full title / English title / replacement relationship

• Standard number: GB/T 8927-2008
• Chinese full title: Petroleum and liquid petroleum products — Temperature measurement — Manual method
• English title: Petroleum and liquid petroleum products—Temperature measurement—Manual methods
• Replacement relationship: replaces GB/T 8927-1988 "Method for temperature measurement of petroleum and liquid petroleum products"
• Adoption relationship: modified adoption of ISO 4268:2000 (MOD), and reference adoption of "Manual of Petroleum Measurement Standards, Chapter 7—Temperature Measurement"
• Publication/implementation: published on 2008-02-13, implemented on 2008-09-01
• Responsible organization: Sinopec Research Institute of Petroleum Processing
• First publication: 1988 year

2. Scope of application and non-applicability

• Applicable: methods, procedures and equipment for manually measuring the temperature of petroleum and petroleum products in storage tanks; storage tanks include road tankers, railway tank cars and oil tanker compartments.
• Preferred method: preferentially use the portable electronic thermometer (PET) given in 4.1 to measure temperature.
• Other usable methods: measurement with a fixed single-point thermometer; measurement by the sampling method using a cup-case thermometer, an overflow cup thermometer, and a thermometer placed in a sample bottle after sampling in accordance with GB/T 4756; in the sampling method, the overflow cup thermometer should be preferentially used to measure temperature.
• Not applicable: only includes manual methods of temperature measurement, and does not include averaging thermometers that form part of an automatic metering system.
• Guidance on related automatic measurement content: for measuring the temperature of oil in atmospheric tanks with a fixed automatic averaging thermometer, see GB/T 21451.4; for measuring the temperature of oil in oil tanker compartments and pressurized tanks, see the corresponding parts of ISO 4266.

3. Method principle

No chapter centrally stating the "method principle" is provided in the available source. The standard specifies manual temperature measurement procedures in separate chapters on equipment, measures, and measurement methods; the temperature measurement error constitutes a relatively large part of the total error in quantity measurement of petroleum and liquid petroleum products (see the introduction).

4. Reagents and materials (purity / preparation)

No dedicated chapter on "reagents and materials" is provided in the available source. Materials/media related to measurement are scattered in various clauses:

• A low-viscosity oil product (such as kerosene or diesel) may be placed in the temperature well to ensure good thermal contact between the temperature well and the thermometer (4.5.2, 6.1.4.6).
• Graphite grease with good conductivity is used in the installation of the angle-stem thermometer (annotation in Figure 5).
• Cleaning: after use for crude oil or fuel oil, the thermometer and cup-case/overflow cup should be cleaned with kerosene or gasoline and wiped dry with a cloth to prevent the formation of a heavy oil insulating film (6.3.3.2 Note 3, 6.3.3.3 Note 2, 6.4.4.2 Note, 6.4.4.3 Note 2).
• When a mercury thermometer is scrapped, measures should be taken to safely preserve the mercury (4.2.5.2 Note).

5. Instruments and equipment

5.1 Portable electronic thermometer (PET) (4.1)

• The minimum resolution shall be 0.1 °C (4.1.2).
• Accuracy: after calibration by comparison with a standard thermometer, the accuracy within the range −10 °C–35 °C is within ±0.2 °C; the accuracy within the ranges −25 °C–−10 °C and 35 °C~100 °C is within ±0.3 °C (the calibration correction value of the standard thermometer shall be applied); the standard thermometer shall be calibrated and qualified by a qualified laboratory (4.1.2).
• Sensing element: resistance type (nickel-wound −200 °C–350 °C; platinum-wound −200 °C–600 °C; copper-wound 40 °C~175 °C), semiconductor type (zero point drift may exist, usually equipped with a zero adjustment device) (4.1.3.1, 4.1.3.2).
• Electrical safety: shall be suitable for the hazardous area in which it is used, have intrinsically safe or explosion-proof characteristics, and can be grounded through the gauge hatch or vapor lock valve (4.1.4).
• Specifications: suitable temperature measurement range; digital display with minimum resolution 0.1 °C; matching instrument case; cable/tape can be immersed in petroleum products for a long time, length sufficient to cover the entire tank depth, can be marked at intervals of every meter or graduated in millimeters; verification device; charger must be charged in a safe area (4.1.5.2).
• Initial calibration: before use, it shall be calibrated and qualified by a qualified calibration laboratory, and a calibration certificate shall be issued, stating the measurement uncertainty, traceability to the national primary standard, calibration date and unique serial number; overall calibration (sensor, cable/tape, electronic circuit and display); the standard thermometer shall be accurate to at least 0.05 °C, with a resolution not lower than 0.02 °C, and traceable to the national primary standard (4.1.5.3).
• Pre-use check: check specifications and damage, battery status, check with a calibrated standard thermometer, check response time; when the change in indicated temperature stabilizes within 0.1 °C for 30 s, equilibrium is established; the response time should usually be less than 15 s (4.1.5.4).
• Storage: the cable/tape shall be wound on a reel; rechargeable instruments shall be charged in time, and non-rechargeable instruments shall have their batteries removed before long-term storage (4.1.5.5).
• Intermediate checks: the difference between the working check and the verification check shall not exceed 0.3 °C; for PET used in custody transfer metering, it is best to do it once a day; verification checks are usually once a month, with at least two temperature points (corresponding to the temperature measurement range 20% and 80%), and the difference shall not exceed 0.3 °C; if exceeded, adjustment and recalibration shall be carried out; recalibration shall be sent to a qualified inspection body according to the period specified by the state (4.1.5.7).

5.2 Liquid-in-glass thermometer (4.2)

• Accuracy and resolution: those used in temperature wells as components of fixed single-point thermometers, and those used in combination in tank sampling methods, shall be consistent with the provisions for PET; with comprehensive consideration, the resolution shall not be lower than 0.2 °C (4.2.2).
• Note 1: for thermometers used in tank sampling methods, when the oil temperature is less than 40 °C, the resolution shall reach 0.1 °C; at 40 °C~80 °C, it shall reach 0.25 °C; when greater than 80 °C, it shall reach 0.5 °C (4.2.2 Note 1).
• Note 2: for thermometers used in tank sampling methods, the accuracy within the range −10 °C–35 °C shall reach ±0.1 °C; within the ranges −40 °C–−10 °C and 35 °C–80 °C, it shall reach ±0.25 °C; within the range 80 °C–120 °C, it shall reach ±0.5 °C (4.2.2 Note 2).
• When used as a standard thermometer: the accuracy shall not be lower than ±0.05 °C, the resolution shall not be lower than 0.02 °C, and it shall be traceable to the corresponding national primary standard (4.2.2).
• General requirements: solid-stem gas-filled (non-air) type (stick type); suitable glass tube with enameled back; temperature sensing bulb made of selected and treated thermometer glass, meeting the performance specified in GB/T 514; the expanded part of the tube diameter shall be more than 10 mm from the graduated part; scale markings clearly etched, line width not exceeding 0.15 mm; indicate immersion depth; mark unique serial number; heat treatment to reduce stress; artificial aging before graduation; standard thermometers shall be calibrated and qualified by a higher-level calibration institution traceable to the national primary standard (4.2.4).
• Intermediate checks: the working check tolerance shall not exceed 0.5 °C; verification check at at least two temperature points (20% and 80%), the reading difference shall not exceed 0.5 °C, and if exceeded, it shall be scrapped; the recalibration period shall not exceed 5 years (4.2.5).
• Protective sleeve: made of thin-walled metal tube, aluminum or aluminum alloy shall not be used; the cutout shall make all graduations clearly visible, and the part enclosing the temperature sensing bulb shall be drilled with a sufficient number of holes; thermometers used in reference measurement or custody transfer metering shall not be equipped with a protective sleeve (4.2.6).
• Selection: only thermometers conforming to the specifications specified in 4.2.2~4.2.3 or equivalent national standards may be used; the expected measurement temperature shall be within the range of the two terminal scale lines, and the temperature to either terminal scale line shall be more than 1 °C; when reading, the line of sight shall be basically perpendicular to the stem tube, and the temperature sensing bulb shall always be immersed in the liquid (4.2.7).
• Error detection: for thermometers used at temperatures exceeding 50 °C, the comparison interval shall not exceed one year; thermometers in daily use shall be checked once a month (4.2.8.1).
• Emergent stem correction: correction value = na (t − tF); for mercury-in-glass thermometers using Celsius temperature, a is approximately 0.00016 (4.2.9).

5.3 Temperature measurement device for tank sampling method (4.3)

• Cup-case thermometer: the cup-case may be made of painted hardwood or non-sparking anti-corrosion material, with a capacity of at least 100 mL, the nearest distance from the temperature sensing bulb to the cup wall shall not be less than 10 mm, and the bottom of the temperature sensing bulb shall be 25 mm±5 mm above the bottom of the cup (4.3.1).
• Overflow cup thermometer: composed of a cylinder with a capacity of at least 200 mL and a rigidly connected thermometer protection tube; shall not be made of aluminum or aluminum alloy; the bottom of the temperature sensing bulb shall be about 25 mm±3 mm above the bottom of the cup; the cylinder body shall be made of oil-resistant insulating material or equipped with an insulating sleeve; there are quick-opening and closing sealing covers at the top and bottom; opening and closing are controlled by a sharp pull of the suspension rope or by remote control (4.3.2.1).
• Sampling bottle method: the capacity of the sampling bottle should usually be not less than 500 mL; it is recommended not to use metal sample bottles (4.3.3).

5.4 Vapor lock sampler and matching thermometer (4.4)

• The vapor lock device shall enable metering or sampling of a pressure tank at the maximum working pressure (4.4.1).
• Sampler example: a glass cylinder with a capacity of about 1 L, with the top and bottom closed by valves positioned by pull pins; the sampling capacity shall not be less than 450 mL; the distance from any part of the temperature sensing bulb to the inside and bottom of the sampler shall not be less than 10 mm (4.4.2).

5.5 Fixed single-point thermometer (4.5)

• Angle-stem thermometer: the graduated portion of the stem forms a certain angle with the rest of the stem and the sensing bulb; the distance from the sensing bulb to the tank wall shall not be less than 500 mm, and it is preferably placed at a position not less than 900 mm from the tank wall (4.5.1).
• Tank-bottom liquid-in-glass thermometer: length is usually 1.3 m, diameter 10 mm; placed in a horizontal or slightly inclined thermowell inserted into the tank wall by at least 900 mm (4.5.2).
• Accuracy and resolution shall meet the requirements in 4.2.2 (4.5.3).

5.6 Dial-type bimetallic-actuated thermometer (4.6)

• Installed into the oil tank through a standard removable metal thermowell; the thermometer stem length shall be at least 500 mm, and the length of the sensing portion shall not exceed 60 mm; connected to the thermowell by threads (4.6.2).
• Measurement data shall not be used for custody transfer metering unless calibration experiments have confirmed that its accuracy and resolution are consistent with other measurement methods in this standard (4.6.3).

6. Recommended operating conditions

• Recommended temperature ranges for thermometers (Table 1):
  • Non-heated oil products in cold climates: −40 °C~30 °C
  • Non-heated oil products in warm climates: −15 °C~40 °C
  • Non-heated oil products in hot climates: 10 °C~65 °C
  • Heated oil products: 35 °C~120 °C
  • Non-heated and heated oil products on ships: 0 °C~80 °C
• Temperature measurement positions and minimum number at different oil depths (Table 2):
  • Oil product depth >4.5 m: minimum 3 points, upper, middle and lower
  • Oil product depth 3.0 m~4.5 m: minimum 2 points, upper and lower
  • Oil product depth <3.0 m: minimum 1 points, middle
  • The upper, middle and lower positions are calculated successively as 6/5, 1/2 and 1/6 of the oil product depth; temperature measurement shall not be carried out at positions less than 150 mm below the oil surface or less than 150 mm above the bottom of the liquid layer (6.1.4.3).
• Recommended immersion times for cup-case thermometers (Table 3):
  • Standard density of oil product <775 kg/m³: when moving 5 min, when stationary 10 min
  • 775 kg/m³~825 kg/m³: when moving 5 min, when stationary 15 min
  • 825 kg/m³~875 kg/m³: when moving 12 min, when stationary 25 min
  • 875 kg/m³~925 kg/m³: when moving 20 min, when stationary 45 min
  • >925 kg/m³: when moving 45 min, when stationary 80 min
• Overflow cup thermometer: repeatedly raise and lower within a height interval of about 0.3 m, overflowing at least 2 min; for viscous oil products heated to above 60 °C, the continuous overflow time shall be increased to 5 min (6.3.3.3, 6.4.4.3).
• Sampling bottle method: the sample bottle is kept at the temperature measurement position for at least 2 min (preferably 3 min); after the thermometer is inserted into the sample, stir slowly until the temperature remains constant (within half of the smallest division) for 20 s (6.3.3.4).
• Pressurized railway tank cars and road tank cars: a non-permanently installed liquid-in-glass thermometer is placed in a thermowell at a position corresponding to the volumetric center of the liquid in the tank, and kept for at least 10 min (6.1.4.6).
• Heated oil products: experience shows that the most reliable temperature is obtained when convection is minimized, which usually occurs 2 h~6 h after the heating line is shut off; temperature shall not be measured in the region within 300 mm of the heating pipe (6.4.2).

7. Sampling and sample preparation

• Temperature measurement shall be carried out through the gauge hatch that can directly contact the bulk oil product in the tank; unless specified in this standard, guide tubes or thermowells shall not be used (3.2 d).
• Before temperature measurement, the height of the liquid in the tank (including free water in the tank) shall first be measured in accordance with GB/T 13894, and the correct liquid level for temperature measurement shall be determined based on the actual oil height after deducting the free water height (3.2 e).
• Related to the sampling method: after sampling in accordance with GB/T 4756, the temperature is measured with a thermometer placed in the sample bottle (Chapter 1); for the sampling bottle method procedure, see 6.3.3.4.
• Floating roof tanks: measure temperature through a perforated gauge pipe or guide tube; if there is no perforated gauge pipe or guide tube, open the cover at the gauge hatch near the gauge platform and measure temperature with a thermometer (6.3.5).

8. Analytical procedure

8.1 General measures (3.2)

• The same method shall be used to measure the liquid temperature in the tank before and after oil product transfer; it is recommended to use the same metering equipment before and after transfer (3.2 a, Note 1).
• When temperature measurement data are used for reference purposes, an experienced metering person shall supervise on site; before the metering person and metering equipment leave the oil storage container, confirmation from the relevant parties shall be obtained, and readings shall be recorded immediately (3.2 b).
• When reading, the thermometer readings at each measurement point, the date and time shall be recorded immediately; the position of the gauge hatch and the liquid level for each temperature measurement (or the position where the sample was collected) shall also be clearly recorded (3.2 c).
• If a metal sheath is used for the liquid-in-glass thermometer, the sensing bulb shall be brought into full contact with the oil product, and it must be kept in the oil product for a sufficient time before reading (3.2 f).
• Avoid the influence of external temperature; temperature shall not be measured in the region within 500 mm of the tank wall in vertical cylindrical oil tanks (3.2 Note 3).
• When temperature measurement data can be obtained from more than one gauge hatch, the liquid level in the tank shall be measured only from the gauge hatch related to the tank capacity table (3.2 Note 4).

8.2 Safety measures (3.3)

• General safety measures include: strictly observe regulations for entering hazardous areas; ladders and platforms are firm and reliable; oil depots and equipment are regularly maintained; metering personnel are equipped with tool kits; portable lamps and flashlights are of explosion-proof type; do not wear shoes, overshoes or clothing that may generate sparks; when opening gauge hatches, take special care with vapor-tight tanks that may be under pressure; ensure metal parts are effectively grounded; ropes shall be made of natural fibers; metering personnel shall first contact the grounded part of the tank; only one gauge hatch shall be opened at a time, and operations shall not be carried out during thunderstorms; temperature measurement equipment shall not be made of aluminum or aluminum alloys; take anti-slip measures when going onto tanks in winter (3.3.2).
• Special safety measures: leaded fuels (3.3.3.1), liquefied petroleum gas (3.3.3.2), pressure tanks and vapor-tight tanks (3.3.3.3, designed to withstand a pressure usually 1.5 times the maximum working pressure design value), floating roof tanks (3.3.3.4), benzene (3.3.3.5).

8.3 Measurement methods (Chapter 6)

• Liquid in pressure tanks (6.1): PET is directly put into the tank through a vapor lock valve for temperature measurement (must be able to withstand the rated pressure of the oil tank); or a thermometer in a thermowell is used; LPG tanks shall have temperature measurement equipment installed in the vapor space; vertical cylindrical tanks, spherical tanks and ellipsoidal tanks are in accordance with Table 2; horizontal cylindrical tanks are measured at heights 5/6, 1/2, 1/6, and the weighted average is calculated as 1/10 of the sum of 3 times upper, 4 times middle, and 3 times lower; spherical segment tanks are measured at volume heights 5/6, 1/2, 1/6; for pressurized railway tank cars and road tank cars see 6.1.4.6.
• Liquid in vapor-tight tanks (6.2): PET is measured through a vapor lock valve; thermometer in a thermowell according to 6.1.4.2; vapor lock sampler with integrated liquid-in-glass thermometer; cup-case thermometer method; overflow cup thermometer method.
• Liquid in atmospheric tanks near ambient temperature (6.3): applicable when the difference between the oil product temperature and the ambient temperature does not exceed 15 °C; PET method, cup-case thermometer method, overflow cup thermometer method, sampling bottle method; vertical cylindrical fixed-roof tanks, vertical cylindrical floating-roof tanks, horizontal cylindrical tanks, road tank cars and railway tank cars, oil tankers.
• Liquid in atmospheric bare tanks with a difference from ambient temperature exceeding 15 °C (6.4): it is best to use PET; the cup-case thermometer shall initially be immersed at least twice (emptying the cup-case after each immersion); the overflow cup thermometer shall initially be rinsed with the oil product in the tank at least twice; for the sampling bottle method, the sampling bottle and sampling cage shall be equilibrated at each sampling position for 5 min.

8.4 Calibration method for fixed tank thermometers (Chapter 7)

• The standard thermometer shall use the PET specified in 4.1, with a measurement resolution not lower than 0.1 °C, calibrated using a traceable temperature reference with a resolution not lower than 0.02 °C, and the measurement uncertainty shall not exceed 0.1 °C at any point within the expected measurement range (7.2).
• Calibration procedure for vertical cylindrical tanks: select measurement points at a distance of more than 500 mm from the tank wall; measure the liquid level; determine the total height of the oil product; calculate the positions 1/10, 3/10, 5/10, 7/10, 9/10; measure point by point; when the variation range of the 5 reference temperatures does not exceed 1.0 °C, take the arithmetic mean; when it exceeds, re-measure according to a uniform distribution of 1/20 (7.3).
• For tanks with inconsistent vertical cross-sectional areas, reference temperature measurement shall be carried out at positions of equal volume intervals (7.4).

8.5 Method of use for fixed single-point thermometers (Chapter 8)

• The thermometer shall be installed in a horizontal or slightly inclined thermowell, with the sensing bulb or sensing element not less than 500 mm from the tank wall and not less than 1 m from the tank bottom; the thermowell preferably extends into the tank by 900 mm (8.2).
• When used for trade metering, the resolution and accuracy shall meet the specification requirements in 4.2.2 (8.3).
• A tank temperature profile inspection shall be performed before use; if the variation range of 5 equally spaced reference measurement data exceeds 1.0 °C or the difference between the fixed single-point thermometer and the average of PET reference measurement data exceeds 0.5 °C, it is not suitable for trade measurement use; the profile inspection shall be repeated at intervals not exceeding 5 years or according to changes in tank service (8.4).

9. Qualitative and Quantitative and Calculation Formulas

• Average temperature calculation: take the arithmetic mean of the measured temperatures at each position as the average temperature of the oil in the tank (6.1.4.3).
• Horizontal cylindrical tank (full or nearly full): calculate the weighted average temperature as 1/10 of the sum of 3 times the upper measured temperature, 4 times the middle measured temperature, and 3 times the lower measured temperature (6.1.4.4).
• Spherical cap tank: if the difference between the middle temperature and the average temperature does not exceed 0.5 °C, take the arithmetic mean of the three temperatures as the average temperature; if the difference exceeds 0.5 °C, take the arithmetic mean of all measured temperatures after supplementary measurement (6.1.4.5).
• Vertical cylindrical fixed-roof tank (one center opening plus several peripheral openings): without rounding, first calculate in sequence the arithmetic mean of the center opening average temperature and the average temperature of each peripheral opening; divide the sum of these arithmetic means by the number of means, and round the result to 0.1 °C (6.3.4.3).
• Railway tank car volume weighting method: multiply the average temperature of each tank's liquid by the volume it contains, add them together, then divide by the total volume; the volume-weighted average calculated thereby is rounded to 0.1 °C (6.3.7).
• Exposed liquid column correction formula (Formula 1): correction value of the reading when the liquid column is exposed = na (t − tF); for mercury-in-glass thermometers using Celsius temperature, a is approximately 0.00016 (4.2.9).
• Tank wall temperature calculation (Formula B.1): ts = [(7×t)+tₐ]/8; ambient temperature accounts for only 1/8 of the total tank wall temperature (ts) (Appendix B).
• Readings and reporting: PET temperature readings shall be read and recorded accurately to 0.1 °C; liquid-in-glass thermometer readings shall be read and recorded accurately to half of the smallest scale division; the average temperature shall be rounded and reported to 0.1 °C (Chapter 5).

10. Precision

The available source does not contain a dedicated chapter on "Precision". Relevant tolerances/verification limits are scattered in various clauses:

• PET working verification: the difference between the two shall not exceed 0.3 °C (4.1.5.7.1).
• PET calibration verification: the difference between the two shall not exceed 0.3 °C (4.1.5.7.2).
• Liquid-in-glass thermometer working verification: the tolerance shall not exceed 0.5 °C (4.2.5.1).
• Liquid-in-glass thermometer calibration verification: the difference between the readings of the two thermometers shall not exceed 0.5 °C (4.2.5.2).
• Fixed single-point thermometer representativeness inspection: when the variation range of 5 equally spaced reference measurement data exceeds 1.0 °C or the difference from the average of PET reference measurements exceeds 0.5 °C, it is not suitable for trade measurement (8.4.1).
• The uncertainty of ambient temperature measurement can reach ±2.5 °C; the thermometer accuracy (maximum permissible error) shall be no lower than 1 °C, and it shall be inspected every three months (Appendix B).

11. Reporting

• Chapter 5 "Readings and Reporting": PET temperature readings shall be read and recorded accurately to 0.1 °C (usually the maximum displayed resolution or the smallest scale division value); liquid-in-glass thermometer temperature readings shall be read and recorded accurately to half of the smallest scale division; the average temperature shall be rounded and reported to 0.1 °C.
• Record contents: thermometer readings at each measurement point, date and time; the position of the gauging opening (including the gauging hatch or vapor lock valve) and the liquid level for each temperature measurement (or the position where the sample was collected) (3.2 c).
• Pressure tank vapor space pressure: usually the vapor space pressure also needs to be measured, and it shall be read and recorded accurately to 10 kPa (6.1.4.2 Note).
• Ambient temperature reporting: shall be accurate to the nearest whole degree (Appendix B).

12. Referenced Documents

• GB/T 514 Technical conditions for liquid-in-glass thermometers for petroleum product testing
• GB/T 4756 Manual sampling of petroleum liquids (GB/T 4756-1998, ISO 3170:1988, MOD)
• GB/T 13894 Liquid level measurement of petroleum and liquid petroleum products (manual method)
• GB/T 19779 Calculation of oil quantities for petroleum and liquid petroleum products — Static measurement
• GB/T 21451.4 Automatic measurement of liquid level and temperature in storage tanks for petroleum and liquid petroleum products — Part 4: Temperature measurement in atmospheric tanks (GB/T 21451.4-2008, ISO 4266-4:2002, MOD)
• ISO 4266-1 Petroleum and liquid petroleum products — Automatic measurement of liquid level and temperature in storage tanks — Part 1: Liquid level measurement in atmospheric tanks
• ISO 4266-2 Petroleum and liquid petroleum products — Automatic measurement of liquid level and temperature in storage tanks — Part 2: Liquid level measurement in ship tanks
• ISO 4266-3 Petroleum and liquid petroleum products — Automatic measurement of liquid level and temperature in storage tanks — Part 3: Liquid level measurement in pressurized tanks
• ISO 4266-5 Petroleum and liquid petroleum products — Automatic measurement of liquid level and temperature in storage tanks — Part 5: Temperature measurement in ship tanks
• ISO 4266-6 Petroleum and liquid petroleum products — Automatic measurement of liquid level and temperature in storage tanks — Part 6: Temperature measurement in pressurized tanks
• Cited in Appendix B: GB/T 13235.1~13235.3 (tank calibration)

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick Reference for Questions and Answers