40 CFR § 63.425 - Test methods and procedures.

§ 63.425 Test methods and procedures.
Link to an amendment published at 89 FR 39361, May 8, 2024.

(a) Performance test and evaluation requirements. Each owner or operator subject to the emission standard in § 63.422(b)(1) or § 60.112b(a)(3)(ii) of this chapter shall comply with the requirements in paragraph (b) of this section. Each owner or operator subject to the emission standard in § 63.422(b)(2) shall comply with the requirements in paragraph (c) of this section. Performance tests shall be conducted under representative conditions when liquid product is being loaded into gasoline cargo tanks and shall include periods between gasoline cargo tank loading (when one cargo tank is disconnected and another cargo tank is moved into position for loading) provided that liquid product loading into gasoline cargo tanks is conducted for at least a portion of each 5 minute block of the performance test. You may not conduct performance tests during periods of malfunction. You must record the process information that is necessary to document operating conditions during the test and include in such record an explanation to support that such conditions represent normal operation. Upon request, you shall make available to the Administrator such records as may be necessary to determine the conditions of performance tests.

(b) Gasoline loading rack and gasoline storage vessel performance test requirements. For gasoline loading racks subject to the requirements in § 63.422(b)(1) or gasoline storage vessels subject to the requirements in § 60.112b(a)(3)(ii) of this chapter:

(1) Conduct a performance test on the vapor processing and collection systems according to either paragraph (b)(1)(i) or (ii) of this section.

(i) Use the test methods and procedures in § 60.503 of this chapter, except a reading of 500 ppm shall be used to determine the level of leaks to be repaired under § 60.503(b) of this chapter, or

(ii) Use alternative test methods and procedures in accordance with the alternative test method requirements in § 63.7(f).

(2) The performance test requirements of § 60.503(c) of this chapter do not apply to flares defined in § 63.421 and meeting the flare requirements in § 63.11(b). The owner or operator shall demonstrate that the flare and associated vapor collection system is in compliance with the requirements in § 63.11(b) and § 60.503(a), (b), and (d) of this chapter, respectively.

(3) For each performance test conducted under paragraph (b)(1) of this section, the owner or operator shall determine a monitored operating parameter value for the vapor processing system using the following procedure:

(i) During the performance test, continuously record the operating parameter under § 63.427(a);

(ii) Determine an operating parameter value based on the parameter data monitored during the performance test, supplemented by engineering assessments and the manufacturer's recommendations; and

(iii) Provide for the Administrator's approval the rationale for the selected operating parameter value, and monitoring frequency and averaging time, including data and calculations used to develop the value and a description of why the value, monitoring frequency, and averaging time demonstrate continuous compliance with the emission standard in § 63.422(b)(1) or § 60.112b(a)(3)(ii) of this chapter.

(4) For performance tests performed after the initial test, the owner or operator shall document the reasons for any change in the operating parameter value since the previous performance test.

(c) Gasoline loading rack performance test and evaluation requirements. For gasoline loading rack sources subject to the requirements in § 63.422(b)(2):

(1) Conduct performance tests or evaluations on the vapor processing and collection systems according to the requirements in § 60.503a(a), (c) and (d) of this chapter.

(2) The first performance test or performance evaluation of the continuous emissions monitoring system (CEMS) shall be conducted within 180 days of the date affected source begins compliance with the requirements in § 63.422(b)(2). A previously conducted performance test may be used to satisfy this requirement if the conditions in paragraphs (c)(2)(i) through (v) of this section are met. Prior to conducting this performance test or evaluation, you must continue to meet the monitoring and operating limits that apply based on the previously conducted performance test.

(i) The performance test was conducted on or after May 8, 2022.

(ii) No changes have been made to the process or control device since the time of the performance test.

(iii) The operating conditions, test methods, and test requirements (e.g., length of test) used for the previous performance test conform to the requirements in paragraph (c)(1) of this section.

(iv) The temperature in the combustion zone was recorded during the performance test as specified in § 60.503a(c)(8)(i) of this chapter and can be used to establish the operating limit as specified in § 60.503a(c)(8)(ii) through (iv) of this chapter.

(v) The performance test demonstrates compliance with the emission limit specified in § 63.422(b)(2).

(3) For loading racks complying with the mass loading emission limit in § 60.502a(c)(1) of this chapter, subsequent performance tests shall be conducted no later than 60 calendar months after the previous performance test.

(4) For loading racks complying with the concentration emission limit in § 60.502a(c)(2) of this chapter, subsequent performance evaluations of CEMS for the vapor collection and processing system shall be conducted no later than 12 calendar months after the previous performance evaluation.

(d) Gasoline storage vessel requirements. The owner or operator of each gasoline storage vessel subject to the provisions of § 63.423 shall comply with § 60.113b of this chapter and, if applicable, the provisions in paragraph (j) of this section. If a closed vent system and control device are used, as specified in § 60.112b(a)(3) of this chapter, to comply with the requirements in § 63.423, the owner or operator shall also comply with the requirements in paragraph (d)(1) or (2) of this section, as applicable.

(1) If the gasoline storage vessel is subject to the provision in § 63.423(a) or the provision in § 63.423(b) and a control device other than a flare is used for the gasoline storage vessel, the owner or operator shall also comply with the requirements in paragraph (b) of this section.

(2) If the gasoline storage vessel is subject to the provision in § 63.423(b) and a flare is used as the control device for the gasoline storage vessel, you must comply with the requirements in § 60.502a(c)(3) of this chapter as indicated in paragraphs (d)(2)(i) and (ii) of this section rather than the requirements in § 60.18(e) and (f) of this chapter as specified in § 60.113b(d) of this chapter.

(i) At § 60.502a(c)(3)(i) of this chapter, replace “vapors displaced from gasoline cargo tanks during product loading” with “vapors from the gasoline storage vessel.”

(ii) Section 60.502a(c)(3)(vi) through (ix) of this chapter does not apply.

(e) Annual certification test. The annual certification test for gasoline cargo tanks shall consist of the following test methods and procedures:

(1) Method 27 of appendix A-8 to part 60 of this chapter. Conduct the test using a time period (t) for the pressure and vacuum tests of 5 minutes. The initial pressure (Pi) for the pressure test shall be 460 millimeters (mm) of water (H2O) (18 inches (in.) H2O), gauge. The initial vacuum (Vi) for the vacuum test shall be 150 mm H2O (6 in. H2O), gauge. Each owner or operator shall implement the requirements in paragraph (e)(1)(i) or (ii) of this section, as applicable in paragraph (e)(1)(iii) of this section.

(i) The maximum allowable pressure and vacuum changes (Δ p, Δ v) are as shown in the second column of table 1 to this paragraph (e)(1).

(ii) The maximum allowable pressure and vacuum changes (Δ p, Δ v) are as shown in the third column of table 1 to this paragraph (e)(1).

(iii) Compliance with the provisions of this section shall be achieved as expeditiously as practicable, but no later than the dates provided in paragraphs (e)(1)(iii)(A) and (B) of this section.

(A) For facilities that commenced construction on or before June 10, 2022, meet the requirements in paragraph (e)(1)(i) of this section prior to May 8, 2027, and meet the requirements in paragraph (e)(1)(ii) of this section no later than May 8, 2027.

(B) For facilities that commenced construction after June 10, 2022, meet the requirements in paragraph (e)(1)(ii) of this section upon startup or July 8, 2024, whichever is later.

Table 1 to Paragraph (e)(1)—Allowable Cargo Tank Test Pressure or Vacuum Change

Cargo tank or compartment capacity, liters (gal) Annual certification-
allowable pressure or
vacuum change
(Δ p, Δ v) in
5 minutes, mm H2O
(in. H2O)
Annual certification-
allowable pressure or
vacuum change
(Δ p, Δ v) in
5 minutes, mm H2O
(in. H2O)]
Allowable pressure
change (Δ p) in
5 minutes at any
time, mm H2O
(in. H2O)
9,464 or more (2,500 or more) 25 (1.0) 12.7 (0.50) 64 (2.5)
9,463 to 5,678 (2,499 to 1,500) 38 (1.5) 19.1 (0.75) 76 (3.0)
5,677 to 3,785 (1,499 to 1,000) 51 (2.0) 25.4 (1.00) 89 (3.5)
3,784 or less (999 or less) 64 (2.5) 31.8 (1.25) 102 (4.0)

(2) Pressure test of the cargo tank's internal vapor valve as follows:

(i) After completing the tests under paragraph (e)(1) of this section, use the procedures in Method 27 to repressurize the tank to 460 mm H2 O (18 in. H2 O), gauge. Close the tank's internal vapor valve(s), thereby isolating the vapor return line and manifold from the tank.

(ii) Relieve the pressure in the vapor return line to atmospheric pressure, then reseal the line. After 5 minutes, record the gauge pressure in the vapor return line and manifold. The maximum allowable 5-minute pressure increase is 130 mm H2 O (5 in. H2 O).

(f) Leak detection test. The leak detection test shall be performed using Method 21 of appendix A-7 to part 60 of this chapter. A vapor-tight gasoline cargo tank shall have no leaks at any time when tested according to the procedures in this paragraph (f).

(1) The instrument reading that defines a leak is 10,000 ppm (as propane). Use propane to calibrate the instrument, setting the span at the leak definition. The response time to 90 percent of the final stable reading shall be less than 8 seconds for the detector with the sampling line and probe attached.

(2) In addition to the procedures in Method 21, include the following procedures:

(i) Perform the test on each compartment during loading of that compartment or while the compartment is still under pressure.

(ii) To eliminate a positive instrument drift, the dwell time for each leak detection shall not exceed two times the instrument response time. Purge the instrument with ambient air between each leak detection. The duration of the purge shall be in excess of two instrument response times.

(iii) Attempt to block the wind from the area being monitored. Record the highest detector reading and location for each leak.

(g) Nitrogen pressure decay field test. For those cargo tanks with manifolded product lines, this test procedure shall be conducted on each compartment.

(1) Record the cargo tank capacity. Upon completion of the loading operation, record the total volume loaded. Seal the cargo tank vapor collection system at the vapor coupler. The sealing apparatus shall have a pressure tap. Open the internal vapor valve(s) of the cargo tank and record the initial headspace pressure. Reduce or increase, as necessary, the initial headspace pressure to 460 mm H2 O (18.0 in. H2 O), gauge by releasing pressure or by adding commercial grade nitrogen gas from a high pressure cylinder capable of maintaining a pressure of 2,000 psig.

(i) The cylinder shall be equipped with a compatible two-stage regulator with a relief valve and a flow control metering valve. The flow rate of the nitrogen shall be no less than 2 cfm. The maximum allowable time to pressurize cargo tanks with headspace volumes of 1,000 gallons or less to the appropriate pressure is 4 minutes. For cargo tanks with a headspace of greater than 1,000 gallons, use as a maximum allowable time to pressurize 4 minutes or the result from the equation below, whichever is greater.

T = Vh × 0.004
where:
T = maximum allowable time to pressurize the cargo tank, min;
Vh = cargo tank headspace volume during testing, gal.

(2) It is recommended that after the cargo tank headspace pressure reaches approximately 460 mm H2 O (18 in. H20), gauge, a fine adjust valve be used to adjust the headspace pressure to 460 mm H2 O (18.0 in. H2 O), gauge for the next 30 ±5 seconds.

(3) Reseal the cargo tank vapor collection system and record the headspace pressure after 1 minute. The measured headspace pressure after 1 minute shall be greater than the minimum allowable final headspace pressure (PF) as calculated from the following equation:

P F = 18 ( ( 18 N ) 18 ) ( V s 5 ( V h ) )

where:
(PF) = minimum allowable final headspace pressure, in. H2 O, gauge;
Vs = total cargo tank shell capacity, gal;
Vh = cargo tank headspace volume after loading, gal;
18.0 = initial pressure at start of test, in. H2 O, gauge;
N = 5-minute continuous performance standard at any time from the fourth column of table 1 to paragraph (e)(1) of this section, inches H2O.

(4) Conduct the internal vapor valve portion of this test by repressurizing the cargo tank headspace with nitrogen to 460 mm H2 O (18 in. H2 O), gauge. Close the internal vapor valve(s), wait for 30 ±5 seconds, then relieve the pressure downstream of the vapor valve in the vapor collection system to atmospheric pressure. Wait 15 seconds, then reseal the vapor collection system. Measure and record the pressure every minute for 5 minutes. Within 5 seconds of the pressure measurement at the end of 5 minutes, open the vapor valve and record the headspace pressure as the “final pressure.”

(5) If the decrease in pressure in the vapor collection system is less than at least one of the interval pressure change values in Table 3 of this paragraph, or if the final pressure is equal to or greater than 20 percent of the 1-minute final headspace pressure determined in the test in paragraph (g)(3) of this section, then the cargo tank is considered to be a vapor-tight gasoline cargo tank.

Table 3—Pressure Change for Internal Vapor Valve Test

Time interval Interval pressure change, mm H2 O (in. H2 O)
After 1 minute 28 (1.1)
After 2 minutes 56 (2.2)
After 3 minutes 84 (3.3)
After 4 minutes 112 (4.4)
After 5 minutes 140 (5.5)

(h) Continuous performance pressure decay test. The continuous performance pressure decay test shall be performed using Method 27 in appendix A to part 60 of this chapter. Conduct only the positive pressure test using a time period (t) of 5 minutes. The initial pressure (Pi) shall be 460 mm H2O (18 in. H2O), gauge. The maximum allowable 5-minute pressure change (Δ p) which shall be met at any time is shown in the fourth column of table 1 to paragraph (e)(1) of this section.

(i) Railcar bubble leak test procedures. As an alternative to paragraph (e) of this section for annual certification leakage testing of gasoline cargo tanks, the owner or operator may comply with paragraphs (i)(1) and (2) of this section for railcar gasoline cargo tanks, provided the railcar tank meets the requirement in paragraph (i)(3) of this section.

(1) Comply with the requirements of 49 CFR 173.31(d), 179.7, 180.509, and 180.511 for the testing of railcar gasoline cargo tanks.

(2) The leakage pressure test procedure required under 49 CFR 180.509(j) and used to show no indication of leakage under 49 CFR 180.511(f) shall be ASTM E 515-95 (incorporated by reference, see § 63.14), BS EN 1593:1999 (incorporated by reference, see § 63.14), or another bubble leak test procedure meeting the requirements in 49 CFR 179.7, 180.505, and 180.509.

(3) The alternative requirements in this paragraph (i) may not be used for any railcar gasoline cargo tank that collects gasoline vapors from a vapor balance system permitted under or required by a Federal, State, local, or tribal agency. A vapor balance system is a piping and collection system designed to collect gasoline vapors displaced from a storage vessel, barge, or other container being loaded, and routes the displaced gasoline vapors into the railcar gasoline cargo tank from which liquid gasoline is being unloaded.

(j) LEL monitoring procedures. Compliance with the vapor concentration below the LEL level for internal floating roof storage vessels at § 63.423(b)(2) shall be determined based on the procedures specified in paragraphs (j)(1) through (5) of this section. If tubing is necessary to obtain the measurements, the tubing must be non-crimping and made of Teflon or other inert material.

(1) LEL monitoring must be conducted at least once every 12 months and at other times upon request by the Administrator. If the measurement cannot be performed due to wind speeds exceeding those specified in paragraph (j)(3)(iii) of this section, the measurement must be performed within 30 days of the previous attempt.

(2) The calibration of the LEL meter must be checked per manufacturer specifications immediately before and after the measurements as specified in paragraphs (j)(2)(i) and (ii) of this section. If tubing will be used for the measurements, the tubing must be attached during calibration so that the calibration gas travels through the entire measurement system.

(i) Conduct the span check using a calibration gas recommended by the LEL meter manufacturer. The calibration gas must contain a single hydrocarbon at a concentration corresponding to 50 percent of the LEL (e.g., 2.50 percent by volume when using methane as the calibration gas). The vendor must provide a Certificate of Analysis for the gas, and the certified concentration must be within ±2 percent (e.g., 2.45 percent—2.55 percent by volume when using methane as the calibration gas). The LEL span response must be between 49 percent and 51 percent. If the span check prior to the measurements does not meet this requirement, the LEL meter must be recalibrated or replaced. If the span check after the measurements does not meet this requirement, the LEL meter must be recalibrated or replaced, and the measurements must be repeated.

(ii) Check the instrumental offset response using a certified compressed gas cylinder of zero air or an ambient environment that is free of organic compounds. The pre-measurement instrumental offset response must be 0 percent LEL. If the LEL meter does not meet this requirement, the LEL meter must be recalibrated or replaced.

(3) Conduct the measurements as specified in paragraphs (j)(3)(i) through (iv) of this section.

(i) Measurements of the vapors within the internal floating roof storage vessel must be collected no more than 3 feet above the internal floating roof.

(ii) Measurements shall be taken for a minimum of 20 minutes, logging the measurements at least once every 15 seconds, or until one 5-minute average as determined according to paragraph (j)(5)(ii) of this section exceeds the level specified in § 63.423(b)(2).

(iii) Measurements shall be taken when the wind speed at the top of the tank is 5 mph or less to the extent practicable, but in no case shall measurements be taken when the sustained wind speed at top of tank is greater than the annual average wind speed at the site or 15 mph, whichever is less.

(iv) Measurements should be conducted when the internal floating roof is floating with limited product movement (limited filling or emptying of the tank).

(4) To determine the actual vapor concentration within the storage vessel, the percent of the LEL “as the calibration gas” must be corrected according to one of the following procedures. Alternatively, if the LEL meter used has correction factors that can be selected from the meter's program, you may enable this feature to automatically apply one of the correction factors specified in paragraphs (j)(4)(i) and (ii) of this section.

(i) Multiply the measurement by the published gasoline vapor correction factor for the specific LEL meter and calibration gas used.

(ii) If there is no published correction factor for gasoline vapors for the specific LEL meter used, multiply the measurement by the published correction factor for butane as a surrogate for determining the LEL of gasoline vapors. The correction factor must correspond to the calibration gas used.

(5) Use the calculation procedures in paragraphs (j)(5)(i) through (iii) of this section to determine compliance with the LEL level.

(i) For each minute while measurements are being taken, determine the one-minute average reading as the arithmetic average of the corrected individual measurements (taken at least once every 15 seconds) during the minute.

(ii) Starting with the end of the fifth minute of data, calculate a five-minute rolling average as the arithmetic average of the previous five one-minute readings determined under paragraph (j)(5)(i) of this section. Determine a new five-minute average reading for every subsequent one-minute reading.

(iii) Each five-minute rolling average must meet the LEL level specified in § 63.423(b)(2).

[59 FR 64318, Dec. 14, 1994; 60 FR 7627, Feb. 8, 1995; 60 FR 32913, June 26, 1995; 68 FR 70965, Dec. 19, 2003; 89 FR 39361, May 8, 2024]