102 records
What is the maximum permissible error for this trade measuring instrument?
102 records covering 11 instrument types, one fact each. Every value is transcribed from the source that states it and carries the sentence it was taken from: 4 sources across 3 sites, last checked 2026-09-01, due for re-check by 2027-09-01. Every record is listed below, each linking the page its value came from.
Records102
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LicenceEU legislation reused under Commission Decision 2011/833/EU on the reuse of documents from the EU institutions. legislation.gov.uk content is Open Government Licence v3.0. NIST Handbook 44 is a work of the United States Government and carries no copyright in the US. OIML R 76-1 states no licence -- OIML publishes its recommendations as free downloads rather than selling them, but it is still a body whose product is partly the compilation, so what is taken here is the fact plus one short attributed quote linking back to the PDF, never the document. The single-publisher volume advisory that applied while this was EU-only is weaker now that three authorities supply the records, and the two largest are legislation published under an explicit reuse decision or free of copyright outright.
Cite as: Accuracy classes and maximum permissible errors for trade measuring instruments, referencesource.org/legal-metrology-accuracy-classes/, checked 2026-09-01.
About this data
Accuracy classes and maximum permissible errors that the law assigns to instruments used for trade, from three authorities that do not publish a common table: Directive 2014/32/EU (the EU Measuring Instruments Directive), Directive 2014/31/EU and OIML R 76-1 (non-automatic weighing instruments), and NIST Handbook 44 code 2.20 (scales, United States). Each record is one instrument type at one accuracy class under one measurement condition, with the permitted error that authority states. The MID side covers nine of the ten instrument-specific annexes: water meters (MI-001), gas meters and volume conversion devices (MI-002), thermal energy meters (MI-004), measuring systems for liquids other than water including fuel dispensers and road tankers (MI-005), automatic weighing instruments (MI-006), taximeters (MI-007), material measures (MI-008), dimensional measuring instruments (MI-009) and exhaust gas analysers (MI-010). Active electrical energy meters (MI-003) carry no records, and that is a statement about the source rather than an omission: Annex V sets its limits in a Table 2 whose load-current bands EUR-Lex renders as images, so neither the band nor the value it pairs with is in the page's text and no row can be keyed to it honestly. Annex VI is thin for the same reason -- every formula in it is an image, so only the flow sensor's 5 % cap, which the directive states in words, is here. Answers 'what is the maximum permissible error for a water meter', 'what accuracy class does a petrol pump have to be', 'MID accuracy class for a taximeter', 'allowed error on a weighbridge', 'thermal energy meter accuracy class 2 MPE', 'is a class III scale legal for trade in both the EU and the US' and 'is my fuel dispenser within tolerance'. The values are condition-dependent -- the error allowed at low flow differs from the error allowed at high flow, and in-service limits differ from new-instrument limits -- so a single percentage figure is almost always the wrong answer. The weighing records are what makes this a juxtaposition rather than a restatement: for a non-automatic weighing instrument the EU directive and OIML R 76-1 state the same three limits over the same load bands, while NIST Handbook 44 adds a fourth band to classes III and IIII and carries a class III L that exists nowhere in Europe. No single document says that, and getting it today means reading a 443,000-character standard, a 300,000-character directive and a 470,000-character handbook side by side.
The data
| Instrument type | Annex | Accuracy class | Condition | Maximum permissible error | Scope or member state option |
|---|---|---|---|---|---|
| Automatic weighing instruments | Annex VIII | Ref(x) | automatic gravimetric filling instrument, static loads, reference class Ref(x) | 0,312 of the maximum permissible deviation of each fill from the average | |
| Automatic weighing instruments | Annex VIII | 0,2 | automatic rail weighbridge, weighing-in-motion, class 0,2 | ± 0,1 % | |
| Automatic weighing instruments | Annex VIII | 0,5 | automatic rail weighbridge, weighing-in-motion, class 0,5 | ± 0,25 % | |
| Automatic weighing instruments | Annex VIII | 1 | automatic rail weighbridge, weighing-in-motion, class 1 | ± 0,5 % | |
| Automatic weighing instruments | Annex VIII | 2 | automatic rail weighbridge, weighing-in-motion, class 2 | ± 1,0 % | |
| Automatic weighing instruments | Annex VIII | 0,5 | continuous totaliser (beltweigher), totalised load, class 0,5 | ± 0,25 % | |
| Automatic weighing instruments | Annex VIII | 1 | continuous totaliser (beltweigher), totalised load, class 1 | ± 0,5 % | |
| Automatic weighing instruments | Annex VIII | 2 | continuous totaliser (beltweigher), totalised load, class 2 | ± 1,0 % | |
| Automatic weighing instruments | Annex VIII | 0,2 | discontinuous totaliser, totalised load, class 0,2 | ± 0,10 % | |
| Automatic weighing instruments | Annex VIII | 0,5 | discontinuous totaliser, totalised load, class 0,5 | ± 0,25 % | |
| Automatic weighing instruments | Annex VIII | 1 | discontinuous totaliser, totalised load, class 1 | ± 0,50 % | |
| Automatic weighing instruments | Annex VIII | 2 | discontinuous totaliser, totalised load, class 2 | ± 1,00 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 2,5 | cryogenic liquids (temperature below – 153 °C), class 2,5 | 2,5 % | |
| Dimensional measuring instruments | Annex XI | area measuring instrument, area of irregular shaped objects (e.g. leather) | 1,0 %, but not less than 1 dm2 | ||
| Dimensional measuring instruments | Annex XI | I | length measuring instrument for rope-type materials, class I | 0,125 %, but not less than 0,005 Lm | |
| Dimensional measuring instruments | Annex XI | II | length measuring instrument for rope-type materials, class II | 0,25 %, but not less than 0,01 Lm | |
| Dimensional measuring instruments | Annex XI | III | length measuring instrument for rope-type materials, class III | 0,5 %, but not less than 0,02 Lm | |
| Dimensional measuring instruments | Annex XI | multidimensional measuring instrument, edge length of the parallelepiped | ± 1,0 d | ||
| Exhaust gas analysers | Annex XII | 0 | CO2 fraction, class 0, rated operating conditions | ± 0,5 % vol ±5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | I | CO2 fraction, class I, rated operating conditions | ± 0,5 % vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | 0 | CO fraction, class 0, rated operating conditions | ± 0,03 % vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | I | CO fraction, class I, rated operating conditions | ± 0,06 % vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | 0 | HC fraction, class 0, rated operating conditions | ± 10 ppm vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | I | HC fraction, class I, rated operating conditions | ± 12 ppm vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | lambda calculation | 0,3 % | ||
| Exhaust gas analysers | Annex XII | 0 | O2 fraction, class 0, rated operating conditions | ± 0,1 % vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Exhaust gas analysers | Annex XII | I | O2 fraction, class I, rated operating conditions | ± 0,1 % vol ± 5 % | For each of the fractions measured, the maximum error value permitted under rated operating conditions according to point 1.1 of Annex I is the greater of the two values shown in Table 2. Absolute values are expressed in % vol or ppm vol, percentage values are percent of the true value. |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | fuel dispensers (not for liquefied gases), class 0,5 | 0,5 % | |
| Gas meters and volume conversion devices | Annex IV | class 1,0, durability test, error of indication | the MPE in point 2 | ||
| Gas meters and volume conversion devices | Annex IV | class 1,0, durability test, variation of the measurement result | one-third of the MPE in point 2 | ||
| Gas meters and volume conversion devices | Annex IV | class 1,5, durability test, error of indication | twice the MPE in point 2 | ||
| Gas meters and volume conversion devices | Annex IV | class 1,5, durability test, variation of the measurement result, Qt to Qmax | 2 % | ||
| Gas meters and volume conversion devices | Annex IV | 1,0 | gas meter at metering conditions or mass, class 1,0, Qmin ≤ Q < Qt | 2 % | |
| Gas meters and volume conversion devices | Annex IV | 1,0 | gas meter at metering conditions or mass, class 1,0, Qt ≤ Q ≤ Qmax | 1 % | |
| Gas meters and volume conversion devices | Annex IV | 1,5 | gas meter at metering conditions or mass, class 1,5, Qmin ≤ Q < Qt | 3 % | |
| Gas meters and volume conversion devices | Annex IV | 1,5 | gas meter at metering conditions or mass, class 1,5, Qt ≤ Q ≤ Qmax | 1,5 % | |
| Gas meters and volume conversion devices | Annex IV | gas meter with temperature conversion, 30 °C range around the specified temperature | increased by 0,5 % | ||
| Gas meters and volume conversion devices | Annex IV | other conversion devices at rated operating conditions | 1 % | ||
| Gas meters and volume conversion devices | Annex IV | temperature conversion devices at rated operating conditions | 0,7 % | ||
| Gas meters and volume conversion devices | Annex IV | volume conversion device at 20 °C ± 3 °C, humidity 60 % ± 15 %, nominal power supply | 0,5 % | ||
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,5 | liquefied carbon dioxide, class 1,5 | 1,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,0 | liquefied gases under pressure at or above – 10 °C, class 1,0 | 1,0 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,5 | liquefied gases under pressure below – 10 °C, not cryogenic, class 1,5 | 1,5 % | |
| Material measures of length | Annex X | between two non-consecutive scale marks, a and b as in Table 1 | (a + bL) | When a terminal interval is bounded by a surface, the MPE for any distance beginning at this point is increased by the value c given in Table 1. | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,3 | measuring systems (line A of Table 2), quantities ≥ 2 litres, class 0,3 | 0,3 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | measuring systems (line A of Table 2), quantities ≥ 2 litres, class 0,5 | 0,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,0 | measuring systems (line A of Table 2), quantities ≥ 2 litres, class 1,0 | 1,0 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,5 | measuring systems (line A of Table 2), quantities ≥ 2 litres, class 1,5 | 1,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 2,5 | measuring systems (line A of Table 2), quantities ≥ 2 litres, class 2,5 | 2,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,3 | meters (line B of Table 2), quantities ≥ 2 litres, class 0,3 | 0,2 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | meters (line B of Table 2), quantities ≥ 2 litres, class 0,5 | 0,3 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,0 | meters (line B of Table 2), quantities ≥ 2 litres, class 1,0 | 0,6 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 1,5 | meters (line B of Table 2), quantities ≥ 2 litres, class 1,5 | 1,0 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 2,5 | meters (line B of Table 2), quantities ≥ 2 litres, class 2,5 | 1,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | milk, class 0,5 | 0,5 % | |
| Non-automatic weighing instruments | I | class I, load 0 ≤ m ≤ 50 000 e, on initial verification | ± 0,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | I | class I, load 50 000 e < m ≤ 200 000 e, on initial verification | ± 1,0 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | I | class I, load 200 000 e < m, on initial verification | ± 1,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | II | class II, load 0 ≤ m ≤ 5 000 e, on initial verification | ± 0,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | II | class II, load 5 000 e < m ≤ 20 000 e, on initial verification | ± 1,0 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | II | class II, load 20 000 e < m ≤ 100 000 e, on initial verification | ± 1,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | III | class III, load 0 ≤ m ≤ 500 e, on initial verification | ± 0,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | III | class III, load 2 000 e < m ≤ 10 000 e, on initial verification | ± 1,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | III | class III, load 500 e < m ≤ 2 000 e, on initial verification | ± 1,0 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | IIII | class IIII, load 0 ≤ m ≤ 50 e, on initial verification | ± 0,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | IIII | class IIII, load 50 e < m ≤ 200 e, on initial verification | ± 1,0 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Non-automatic weighing instruments | IIII | class IIII, load 200 e < m ≤ 1 000 e, on initial verification | ± 1,5 e | The maximum permissible errors in service are twice the maximum permissible errors fixed in Section 4.1. | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,3 | pipeline, class 0,3 | 0,3 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | refuelling aircraft, class 0,5 | 0,5 % | |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | road tankers for liquids of low viscosity (< 20 mPa.s), class 0,5 | 0,5 % | |
| Scales | I | class I, test load 0 to 50 000 e, maintenance tolerance | 1 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | I | class I, test load 50 001 to 200 000 e, maintenance tolerance | 2 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | I | class I, test load 200 001 + e, maintenance tolerance | 3 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | II | class II, test load 0 to 5 000 e, maintenance tolerance | 1 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | II | class II, test load 5 001 to 20 000 e, maintenance tolerance | 2 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | II | class II, test load 20 001 + e, maintenance tolerance | 3 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | III L | class III L, test load 0 to 500 e, maintenance tolerance | 1 | Add 1 e for each additional 500 e or fraction thereof (Only applies to Class III L) | |
| Scales | III L | class III L, test load 501 to 1 000 e, maintenance tolerance | 2 | Add 1 e for each additional 500 e or fraction thereof (Only applies to Class III L) | |
| Scales | III | class III, test load 0 to 500 e, maintenance tolerance | 1 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | III | class III, test load 2 001 to 4 000 e, maintenance tolerance | 3 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | III | class III, test load 4 001 + e, maintenance tolerance | 5 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | III | class III, test load 501 to 2 000 e, maintenance tolerance | 2 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | IIII | class IIII, test load 0 to 50 e, maintenance tolerance | 1 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | IIII | class IIII, test load 51 to 200 e, maintenance tolerance | 2 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | IIII | class IIII, test load 201 to 400 e, maintenance tolerance | 3 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Scales | IIII | class IIII, test load 401 + e, maintenance tolerance | 5 | The acceptance tolerance values shall be one-half the maintenance tolerance values. | |
| Taximeters | Annex IX | calculation of the fare (minimum: the least significant digit of the indication) | ± 0,1 % | ||
| Taximeters | Annex IX | distance travelled (minimum value of mpe: 4 m) | ± 0,2 % | ||
| Taximeters | Annex IX | real-time clock timekeeping | 0,02 % | ||
| Taximeters | Annex IX | time elapsed (minimum value of mpe: 0,2 s) | ± 0,1 % | ||
| Thermal energy meters | Annex VI | 1 | flow sensor sub-assembly, class 1 | not more than 5 % | |
| Thermal energy meters | Annex VI | 2 | flow sensor sub-assembly, class 2 | not more than 5 % | Where a Member State imposes measurement of commercial and/or light industrial use, it is authorised to require any Class 2 meter. |
| Thermal energy meters | Annex VI | 3 | flow sensor sub-assembly, class 3 | not more than 5 % | Where a Member State imposes measurement of residential use, it shall allow such measurement to be performed by means of any Class 3 meter. |
| Measuring systems for the continuous and dynamic measurement of quantities of liquids other than water | Annex VII | 0,5 | (un)loading ships and rail and road tankers, class 0,5 | 0,5 % | However, Member States may require measuring systems of accuracy class 0,3 or 0,5 when used for the levying of duties on mineral oils when (un)loading ships and rail and road tankers. |
| Water meters | Annex III | durability test, error of indication, Q1 to Q2 excluded | ± 6 % | ||
| Water meters | Annex III | durability test, error of indication, Q2 to Q4, water 0,1 °C to 30 °C | ± 2,5 % | ||
| Water meters | Annex III | durability test, error of indication, Q2 to Q4, water 30 °C to 90 °C | ± 3,5 % | ||
| Water meters | Annex III | durability test, variation of the measurement result, Q1 to Q2 excluded | 3 % | ||
| Water meters | Annex III | durability test, variation of the measurement result, Q2 to Q4 included | 1,5 % | ||
| Water meters | Annex III | Q1 ≤ Q < Q2 (excluded), any water temperature | 5 % | ||
| Water meters | Annex III | Q2 (included) ≤ Q ≤ Q4, water above 30 °C | 3 % | ||
| Water meters | Annex III | Q2 (included) ≤ Q ≤ Q4, water up to 30 °C | 2 % |
Where this came from
Every record above links the page it was taken from and quotes the sentence that states it. These are the 4 sources this dataset was assembled from.
- eur-lex.europa.euhttps://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32014L0032
- eur-lex.europa.euhttps://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32014L0031
- oiml.orghttps://www.oiml.org/en/files/pdf_r/r076-1-e06.pdf
- nist.govhttps://www.nist.gov/document/2026-nist-handbook-44-section-220
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