{
  "name": "How far off a US fuel pump, LPG meter or EV charger is allowed to be (NIST Handbook 44)",
  "description": "The accuracy every commercial device that sells fuel or energy in the United States has to hold, taken from NIST Handbook 44 -- the specifications and tolerances that state weights-and-measures programs adopt by reference and enforce when they inspect a gas pump. Each record is one row of one tolerance table: the commodity or device the row covers, its accuracy class, and the three limits the handbook prints for it. Answers 'how accurate does a gas pump have to be' (a retail petrol or diesel dispenser is Accuracy Class 0.5: 0.5 % once in service, 0.3 % when newly installed), 'is a new dispenser held to a tighter standard than one already in service' (yes -- the acceptance tolerance for a new or newly repaired device is tighter than the maintenance tolerance that applies afterwards), and the same question for propane, anhydrous ammonia, CNG, hydrogen, liquid CO2, cryogenic products and EV chargers. Covers Handbook 44 sections 3.30 (liquid-measuring devices), 3.31 (vehicle-tank meters), 3.32 (LPG and anhydrous ammonia), 3.33 (hydrocarbon gas vapor), 3.34 (cryogenic), 3.37 (mass flow meters), 3.38 (carbon dioxide), 3.39 (hydrogen) and 3.40 (electric vehicle fueling systems). Three things to read alongside the numbers. First, the handbook footnotes that special test tolerances do not apply to retail motor fuel or retail Diesel Exhaust Fluid dispensers at all, so the special-test column in section 3.30 is not a limit a filling-station pump is held to; that footnote is carried here as its own record. Second, the Accuracy Class 0.5 percentages stop applying on a small test draft: in section 3.30, a draft of 40 L (10 gal) or less is held to a volume figure instead of a percentage, and in section 3.31 to 6 in3 for a 5 gallon draft and 11 in3 for a 10 gallon one. The section 3.30 version of that exception is a record here. Third, this is a first pass over a source published only as a PDF: a table row is included only where the device, the class and the printed limits sit in one continuous run of text, so a handful of rows whose bullets are split across a page break by the PDF's running footer are not yet here -- section 3.30's Accuracy Class 0.3 row is the notable omission, and the equivalent row is present from sections 3.31 and 3.37. Nothing is reconstructed across a break; a row we cannot quote whole is left out.",
  "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/",
  "licence": "NIST Handbook 44 is a work of the US federal government and carries no copyright. Values are quoted with the section they appear in and link back to the NIST-hosted PDF.",
  "last_verified": "2026-08-20",
  "stale_after": "2027-08-20",
  "sources": [
    "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-332",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-333",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-334",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-338",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-339",
    "https://www.nist.gov/document/2026-nist-handbook-44-section-340"
  ],
  "records": [
    {
      "application": "Asphalt at temperatures greater than 50 \u00b0C (122 \u00b0F)",
      "accuracy_class": "0.3A",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.3 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-0-3a-asphalt-at-temperatures-greater-than-50-c-122-f",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-0-3a-asphalt-at-temperatures-greater-than-50-c-122-f/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "0.3A - Asphalt at temperatures greater than 50 \u00b0C (122 \u00b0F) 0.3 % 0.3 % 0.5 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Agri-chemical liquids",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.5 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-0-5-agri-chemical-liquids",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-0-5-agri-chemical-liquids/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "- Petroleum products delivered from small capacity (at 4 L/min (1 gpm) through 115 L/min or 30 gpm)** motor-fuel devices 0.5* 0.3 % 0.5 % 0.5 % - Agri-chemical liquids - All other applications not shown in the table where the typical delivery is \u2264 200 L (50 gal)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Petroleum products delivered from small capacity (at 4 L/min (1 gpm) through 115 L/min or 30 gpm)** motor-fuel devices",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.5 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-0-5-petroleum-products-delivered-from-small-capacity-at-4-l-min-1-gpm-through-115-l-",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-0-5-petroleum-products-delivered-from-small-capacity-at-4-l-min-1-gpm-through-115-l-/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "- Petroleum products delivered from small capacity (at 4 L/min (1 gpm) through 115 L/min or 30 gpm)** motor-fuel devices 0.5* 0.3 % 0.5 % 0.5 % - Agri-chemical liquids - All other applications not shown in the table where the typical delivery is \u2264 200 L (50 gal)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Devices designed to deliver less than 1 gal",
      "accuracy_class": "1.1",
      "acceptance_tolerance": "0.75 %",
      "maintenance_tolerance": "1.0 %",
      "special_test_tolerance": "1.25 %",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-1-1-devices-designed-to-deliver-less-than-1-gal",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-1-1-devices-designed-to-deliver-less-than-1-gal/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "- Petroleum products and other normal liquids from 1.1 devices with flow rates** less than 1 gpm. 0.75 % 1.0 % 1.25 % - Devices designed to deliver less than 1 gal",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "test drafts \u2264 40 L or 10 gal",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "one-half the maintenance tolerance values",
      "maintenance_tolerance": "20 mL plus 4 mL per indicated liter or 1 in3 plus 1 in3 per indicated gallon",
      "test_condition": "normal and special tests",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-normal-and-special-tests-0-5-test-drafts-40-l-or-10-gal",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-normal-and-special-tests-0-5-test-drafts-40-l-or-10-gal/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "* For test drafts \u2264 40 L or 10 gal, the tolerances specified for Accuracy Class 0.5 in the table above do not apply. For these test drafts, the following applies: (a) Maintenance tolerances on normal and special tests shall be 20 mL plus 4 mL per indicated liter or 1 in3 plus 1 in3 per indicated gallon. (b) Acceptance tolerances on normal and special tests shall be one-half the maintenance tolerance values.",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "retail motor fuel and retail Diesel Exhaust Fluid (DEF) dispensers",
      "special_test_tolerance": "not applicable",
      "handbook_section": "3.30. Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-30-liquid-measuring-devices-retail-motor-fuel-and-retail-diesel-exhaust-fluid-def-dispensers",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-30-liquid-measuring-devices-retail-motor-fuel-and-retail-diesel-exhaust-fluid-def-dispensers/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-330",
      "source_quote": "Special test tolerances are not applicable to retail motor fuel and retail Diesel Exhaust Fluid (DEF) dispensers.",
      "verified_fields": [
        "application",
        "edition",
        "handbook_section",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Asphalt at temperatures greater than 50 \u00b0C",
      "accuracy_class": "0.3A",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.3 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-0-3a-asphalt-at-temperatures-greater-than-50-c",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-0-3a-asphalt-at-temperatures-greater-than-50-c/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "- Asphalt at temperatures greater than 50 \u00b0C 0.3A 0.3 % 0.3 % 0.5 % (122 \u00b0F)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Petroleum products delivered from large capacity (flow rates over 115 L/min or 30 gpm)** devices, including motor-fuel devices",
      "accuracy_class": "0.3",
      "acceptance_tolerance": "0.15 %",
      "maintenance_tolerance": "0.3 %",
      "special_test_tolerance": "0.45 %",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-0-3-petroleum-products-delivered-from-large-capacity-flow-rates-over-115-l-min-or-30",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-0-3-petroleum-products-delivered-from-large-capacity-flow-rates-over-115-l-min-or-30/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "- Petroleum products delivered from large capacity (flow rates over 115 L/min or 30 gpm)** devices, including motor-fuel devices - Heated products (other than asphalt) at 0.3 temperatures greater than 50 \u00b0C (122 \u00b0F) 0.15 % 0.3 % 0.45 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Petroleum products delivered from small capacity (at 4 L/min (1 gpm) through 115 L/min or 30 gpm)** motor-fuel devices",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.5 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-0-5-petroleum-products-delivered-from-small-capacity-at-4-l-min-1-gpm-through-115-l-",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-0-5-petroleum-products-delivered-from-small-capacity-at-4-l-min-1-gpm-through-115-l-/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "- Petroleum products delivered from small capacity (at 4 L/min (1 gpm) through 115 L/min or 30 gpm)** motor-fuel devices 0.5* 0.3 % 0.5 % 0.5 % - Agri-chemical liquids - All other applications not shown in the table where the typical delivery is \u2264 200 L (50 gal)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Devices designed to deliver less than 4 L (1 gal)",
      "accuracy_class": "1.1",
      "acceptance_tolerance": "0.75 %",
      "maintenance_tolerance": "1.0 %",
      "special_test_tolerance": "1.25 %",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-1-1-devices-designed-to-deliver-less-than-4-l-1-gal",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-1-1-devices-designed-to-deliver-less-than-4-l-1-gal/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "- Petroleum products and other normal liquids from devices with flow rates** less than 4 L/min 1.1 0.75 % 1.0 % 1.25 % (1 gpm) and - Devices designed to deliver less than 4 L (1 gal)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "5 gal and 10 gal test drafts",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "3 in3 and 5.5 in3",
      "maintenance_tolerance": "6 in3 and 11 in3",
      "test_condition": "normal and special tests",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-normal-and-special-tests-0-5-5-gal-and-10-gal-test-drafts",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-normal-and-special-tests-0-5-5-gal-and-10-gal-test-drafts/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "* For 5 gal and 10 gal test drafts, the tolerances specified for Accuracy Class 0.5 in the table above do not apply. For these test drafts, the maintenance tolerances on normal and special tests for 5 gal and 10 gal test drafts are 6 in3 and 11 in3, respectively. Acceptance tolerances on normal and special tests are 3 in3 and 5.5 in3.",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "Water",
      "accuracy_class": "1.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "1.5 %",
      "special_test_tolerance": "1.5 %",
      "test_condition": "Overregistration",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-overregistration-1-5-water",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-overregistration-1-5-water/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "Overregistration 1.5 % 1.5 % 1.5 % 1.5 - Water",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "Water",
      "accuracy_class": "1.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "1.5 %",
      "special_test_tolerance": "5.0 %",
      "test_condition": "Underregistration",
      "handbook_section": "3.31. Vehicle-Tank Meters",
      "edition": "2026",
      "id": "3-31-vehicle-tank-meters-underregistration-1-5-water",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-31-vehicle-tank-meters-underregistration-1-5-water/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-331",
      "source_quote": "1.5 - Water Underregistration 1.5 % 1.5 % 5.0 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "Anhydrous ammonia, LPG",
      "accuracy_class": "1.0",
      "acceptance_tolerance": "0.6 %",
      "maintenance_tolerance": "1.0 %",
      "special_test_tolerance": "1.0 %",
      "handbook_section": "3.32. LPG and Anhydrous Ammonia Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-32-lpg-and-anhydrous-ammonia-liquid-measuring-devices-1-0-anhydrous-ammonia-lpg",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-32-lpg-and-anhydrous-ammonia-liquid-measuring-devices-1-0-anhydrous-ammonia-lpg/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-332",
      "source_quote": "Anhydrous ammonia, LPG 1.0 0.6 % 1.0 % 1.0 % (including vehicle-mounted meters)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Gases at low pressure",
      "accuracy_class": "3.0",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "1.5 %",
      "test_condition": "Overregistration",
      "handbook_section": "3.33. Hydrocarbon Gas Vapor-Measuring Devices",
      "edition": "2026",
      "id": "3-33-hydrocarbon-gas-vapor-measuring-devices-overregistration-3-0-gases-at-low-pressure",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-33-hydrocarbon-gas-vapor-measuring-devices-overregistration-3-0-gases-at-low-pressure/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-333",
      "source_quote": "Gases at low pressure Overregistration 1.5 % 1.5 % 3.0 (for example, LPG vapor) Underregistration 3.0 % 3.0 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "Gases at low pressure",
      "accuracy_class": "3.0",
      "acceptance_tolerance": "3.0 %",
      "maintenance_tolerance": "3.0 %",
      "test_condition": "Underregistration",
      "handbook_section": "3.33. Hydrocarbon Gas Vapor-Measuring Devices",
      "edition": "2026",
      "id": "3-33-hydrocarbon-gas-vapor-measuring-devices-underregistration-3-0-gases-at-low-pressure",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-33-hydrocarbon-gas-vapor-measuring-devices-underregistration-3-0-gases-at-low-pressure/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-333",
      "source_quote": "Gases at low pressure Overregistration 1.5 % 1.5 % 3.0 (for example, LPG vapor) Underregistration 3.0 % 3.0 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "Cryogenic products; liquefied compressed gases",
      "accuracy_class": "2.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "2.5 %",
      "special_test_tolerance": "2.5 %",
      "handbook_section": "3.34. Cryogenic Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-34-cryogenic-liquid-measuring-devices-2-5-cryogenic-products-liquefied-compressed-gases",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-34-cryogenic-liquid-measuring-devices-2-5-cryogenic-products-liquefied-compressed-gases/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-334",
      "source_quote": "Cryogenic products; liquefied compressed gases 2.5 1.5 % 2.5 % 2.5 % other than liquid carbon dioxide",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Asphalt at temperatures greater than 50 \u00b0C",
      "accuracy_class": "0.3A",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.3 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-0-3a-asphalt-at-temperatures-greater-than-50-c",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-0-3a-asphalt-at-temperatures-greater-than-50-c/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "0.3A - Asphalt at temperatures greater than 50 \u00b0C 0.3 % 0.3 % 0.5 % (122 \u00b0F)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Large capacity motor-fuel dispensers",
      "accuracy_class": "0.3",
      "acceptance_tolerance": "0.2 %",
      "maintenance_tolerance": "0.3 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-0-3-large-capacity-motor-fuel-dispensers",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-0-3-large-capacity-motor-fuel-dispensers/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "0.3 - Large capacity motor-fuel dispensers (maximum 0.2 % 0.3 % 0.5 % discharge flow rates greater than 100 L/min or 25 gal/min)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Small capacity (retail) motor-fuel dispensers",
      "accuracy_class": "0.5",
      "acceptance_tolerance": "0.3 %",
      "maintenance_tolerance": "0.5 %",
      "special_test_tolerance": "0.5 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-0-5-small-capacity-retail-motor-fuel-dispensers",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-0-5-small-capacity-retail-motor-fuel-dispensers/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "0.5 - Small capacity (retail) motor-fuel dispensers 0.3 % 0.5 % 0.5 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Anhydrous ammonia",
      "accuracy_class": "1.0",
      "acceptance_tolerance": "0.6 %",
      "maintenance_tolerance": "1.0 %",
      "special_test_tolerance": "1.0 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-1-0-anhydrous-ammonia",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-1-0-anhydrous-ammonia/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "1.0 - Anhydrous ammonia 0.6 % 1.0 % 1.0 % - LP Gas (including vehicle-tank meters)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "LP Gas (including vehicle-tank meters)",
      "accuracy_class": "1.0",
      "acceptance_tolerance": "0.6 %",
      "maintenance_tolerance": "1.0 %",
      "special_test_tolerance": "1.0 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-1-0-lp-gas-including-vehicle-tank-meters",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-1-0-lp-gas-including-vehicle-tank-meters/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "1.0 - Anhydrous ammonia 0.6 % 1.0 % 1.0 % - LP Gas (including vehicle-tank meters)",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Compressed natural gas as a motor-fuel",
      "accuracy_class": "2.0",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "2.0 %",
      "special_test_tolerance": "2.0 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-2-0-compressed-natural-gas-as-a-motor-fuel",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-2-0-compressed-natural-gas-as-a-motor-fuel/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "2.0 - Compressed natural gas as a motor-fuel 1.5 % 2.0 % 2.0 % - All other hydrocarbon gases and any other hydrocarbon gas/air mix applications not shown in the table",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Cryogenic liquid meters",
      "accuracy_class": "2.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "2.5 %",
      "special_test_tolerance": "2.5 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-2-5-cryogenic-liquid-meters",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-2-5-cryogenic-liquid-meters/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "2.5 - Cryogenic liquid meters 1.5 % 2.5 % 2.5 % - Liquefied compressed gases other than LP Gas",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Liquefied compressed gases other than LP Gas",
      "accuracy_class": "2.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "2.5 %",
      "special_test_tolerance": "2.5 %",
      "handbook_section": "3.37. Mass Flow Meters",
      "edition": "2026",
      "id": "3-37-mass-flow-meters-2-5-liquefied-compressed-gases-other-than-lp-gas",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-37-mass-flow-meters-2-5-liquefied-compressed-gases-other-than-lp-gas/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-337",
      "source_quote": "2.5 - Cryogenic liquid meters 1.5 % 2.5 % 2.5 % - Liquefied compressed gases other than LP Gas",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Liquid carbon dioxide",
      "accuracy_class": "2.5",
      "acceptance_tolerance": "1.5 %",
      "maintenance_tolerance": "2.5 %",
      "special_test_tolerance": "2.5 %",
      "handbook_section": "3.38. Carbon Dioxide Liquid-Measuring Devices",
      "edition": "2026",
      "id": "3-38-carbon-dioxide-liquid-measuring-devices-2-5-liquid-carbon-dioxide",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-38-carbon-dioxide-liquid-measuring-devices-2-5-liquid-carbon-dioxide/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-338",
      "source_quote": "2.5 Liquid carbon dioxide 1.5 % 2.5 % 2.5 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "special_test_tolerance"
      ]
    },
    {
      "application": "Hydrogen gas as a vehicle fuel",
      "accuracy_class": "7.0",
      "acceptance_tolerance": "5.0 %",
      "maintenance_tolerance": "7.0 %",
      "handbook_section": "3.39. Hydrogen Gas-Measuring Devices",
      "edition": "2026",
      "id": "3-39-hydrogen-gas-measuring-devices-7-0-hydrogen-gas-as-a-vehicle-fuel",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-39-hydrogen-gas-measuring-devices-7-0-hydrogen-gas-as-a-vehicle-fuel/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-339",
      "source_quote": "7.0 Hydrogen gas as a vehicle fuel 5.0 % 7.0 %",
      "verified_fields": [
        "acceptance_tolerance",
        "accuracy_class",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance"
      ]
    },
    {
      "application": "a DC system that was placed in service prior to January 1, 2025, and that is marked Class 5",
      "acceptance_tolerance": "5.0 %",
      "maintenance_tolerance": "5.0 %",
      "test_condition": "acceptance and maintenance tolerances",
      "handbook_section": "3.40. Electric Vehicle Fueling Systems",
      "edition": "2026",
      "id": "3-40-electric-vehicle-fueling-systems-acceptance-and-maintenance-tolerances-a-dc-system-that-was-placed-in-service-prior-to-january-1-2025-and-that-is-marke",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-40-electric-vehicle-fueling-systems-acceptance-and-maintenance-tolerances-a-dc-system-that-was-placed-in-service-prior-to-january-1-2025-and-that-is-marke/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-340",
      "source_quote": "shall be as follows: (a) For a DC system that was placed in service prior to January 1, 2025, and that is marked Class 5, acceptance and maintenance tolerances are: 5.0 %. This paragraph T.2.2.(a) shall expire on January 1, 2034; after that date, all DC EVSEs shall be subject to the tolerances of paragraph T.2.2.(b).",
      "verified_fields": [
        "acceptance_tolerance",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance",
        "test_condition"
      ]
    },
    {
      "application": "any DC system not subject to paragraph T.2.2.(a)",
      "acceptance_tolerance": "1.0 %",
      "maintenance_tolerance": "2.0 %",
      "handbook_section": "3.40. Electric Vehicle Fueling Systems",
      "edition": "2026",
      "id": "3-40-electric-vehicle-fueling-systems-any-dc-system-not-subject-to-paragraph-t-2-2-a",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-40-electric-vehicle-fueling-systems-any-dc-system-not-subject-to-paragraph-t-2-2-a/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-340",
      "source_quote": "(b) For any DC system not subject to paragraph T.2.2.(a), tolerances are: (1) Acceptance Tolerance: 1.0 %; and (2) Maintenance Tolerance: 2.0 %.",
      "verified_fields": [
        "acceptance_tolerance",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance"
      ]
    },
    {
      "application": "EVSE load tests for AC Systems",
      "acceptance_tolerance": "1.0 %",
      "maintenance_tolerance": "2.0 %",
      "handbook_section": "3.40. Electric Vehicle Fueling Systems",
      "edition": "2026",
      "id": "3-40-electric-vehicle-fueling-systems-evse-load-tests-for-ac-systems",
      "url": "https://referencesource.org/motor-fuel-dispenser-measurement-tolerances-nist/3-40-electric-vehicle-fueling-systems-evse-load-tests-for-ac-systems/",
      "source": "https://www.nist.gov/document/2026-nist-handbook-44-section-340",
      "source_quote": "T.2.1. EVSE Accuracy Test Tolerances for AC Systems. \u2013 The tolerances for EVSE load tests for AC Systems are: (a) Acceptance Tolerance: 1.0 %; and (b) Maintenance Tolerance: 2.0 %.",
      "verified_fields": [
        "acceptance_tolerance",
        "application",
        "edition",
        "handbook_section",
        "maintenance_tolerance"
      ]
    }
  ]
}