⛽ Total contamination (undissolved substances) in pure fatty acid methyl esters (FAME) — gravimetric method, working range 5–27 mg/kg; PN-EN 12662-2

Petrochemistry PN-EN 12662-2

Overview

WHAT THE STANDARD COVERS. According to the scope description of EN 12662-2:2024 in the iTeh catalogue, the document specifies a method for determining the content of undissolved substances, called total contamination, in pure fatty acid methyl esters (FAME). The working range is 5–27 mg/kg; it was established in an interlaboratory study using EN ISO 4259-1. The standard applies generally to FAME with a kinematic viscosity not exceeding 8 mm²/s at 20 °C or 5 mm²/s at 40 °C, e.g. according to EN 14214; the method can be used for FAME of higher viscosity, but its precision has then not been determined. The "Scope" field of the PKN card of PN-EN 12662-2:2024-11 (Polish version): "This document gives a method for determining the content of insoluble substances, referred to as total contamination, in pure fatty acid methyl esters (FAME). The working range is from 5 mg/kg to 27 mg/kg and was established in interlaboratory studies using EN ISO 4259-1. This document applies mainly to FAME with a kinematic viscosity not exceeding 8 mm²/s at a temperature of 20 °C or 5 mm²/s at a temperature of 40 °C, e.g. as specified in EN 14214. This test method can be used for FAME with a kinematic viscosity exceeding 8 mm²/s at a temperature of 20°C or 5 mm²/s at a temperature of 40°C, but in such cases the precision of the test method has not been determined" (our translation) — the card then gives a note on the designation "% (V/V)" and a safety warning.

WHY TWO PARTS (foreword and introduction of EN 12662-2:2024). The document was prepared by committee CEN/TC 19 and supersedes EN 12662:2014. Technical changes: the scope of the previous edition was split into two parts — part 2 covers pure FAME, and part 1 (a separate document) middle distillates and diesel fuels with FAME up to 30 % (V/V) — and the precision data were updated after a statistical analysis of interlaboratory studies according to EN ISO 4259-1:2017. The introduction explains that excessive contamination of the fuel system can cause premature filter blocking and damage, and that the improvements of 2014 caused problems in laboratories when testing FAME and when comparing results with the earlier version of the method; the solution was the split: the previous version as part 1 and a separate standard for pure FAME as part 2, with precision determined in a new interlaboratory study. Conflicting national standards were to be withdrawn at the latest in December 2024. Contents: principle (clause 4), reagents and materials (5), apparatus (6), cleaning of sample containers and of the filtration assembly (7), sampling (8), preparation of the test portion — pure FAME (9.2), preparation of the filtration assembly and filter (10), procedure (11), calculation (12), precision — repeatability and reproducibility (14). The determination of total contamination in diesel fuels according to part 1 is described in a separate entry of this database.

REGULATIONS. Regulation of the Minister of Energy of 16 September 2025 on test methods for the quality of liquid biofuels (Journal of Laws 2025 item 1341, "in force" in the ELI database of the Sejm, read on 27.10.2026), part I (methyl ester as a self-contained fuel), points 16–16.3: a specified quantity of the prepared sample is filtered under vacuum through a previously weighed filter, the filter with the residue is washed, dried and weighed, and the contamination content is calculated from the difference in filter masses relative to the mass of the sample, in mg/kg; the procedure, reagents, apparatus, calculation and report are specified by the Polish Standard adopting EN 12662-2, and the precision — by Annex A to standard PN-EN 14214. For diesel fuel with 20 % methyl ester (part II, point 11.2) the same regulation cites the standard adopting EN 12662-1. Requirement: regulation on quality requirements for liquid biofuels (Journal of Laws 2025 item 426, in the ELI database "act covered by a consolidated text"), Annex No 1, item 19 — total contamination in FAME as a self-contained fuel at most 24 mg/kg.

STATUS (PKN card as of 27.10.2026). The card of PN-EN 12662-2:2024-11 (Polish version) has no withdrawal label: publication 12-02-2026, 16 pages, Chemistry Sector, KT 222/PK 1 Liquid Fuels, "Adopts: EN 12662-2:2024 [IDT]", "Replaces: PN-EN 12662:2014-05 - Polish version, PN-EN 12662:2014-05 - English version", ICS 75.160.20 and 75.160.40. PKN search, search term "EN 12662" (27.10.2026): alongside it there is the English version PN-EN 12662-2:2024-11 and part 1 — PN-EN 12662-1:2024-11 (Polish and English versions); earlier editions of PN-EN 12662 from 2002, 2003, 2008, 2009 and 2014-05 are withdrawn, and PN-EN 12662:2014-05 was replaced by both parts of 2024. In the iTeh catalogue (read on 27.10.2026) EN 12662-2:2024 has the status "Published".

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database refreshed from the production server on 27.10.2026 and current PCA documents downloaded on that day). Number 12662-2 appears in 19 records at 8 Polish laboratories: AB 009, AB 079, AB 098, AB 103, AB 387 (five liquid fuel laboratories: Nowa Wieś Wielka, Koluszki, Emilianów, Rejowiec, Boronów), AB 484 (eight laboratories and service points), AB 1668, AB 1679. In all 8 current PCA documents the standard is in the same 19 rows; no entry is suspended. Forms: "PN-EN 12662-2:2024-11" (AB 079, AB 103, AB 484, AB 1668, AB 1679) and "PN-EN 12662-2" without the year (AB 009, AB 098, AB 387). AB 098 has three documents in one entry at once: PN-EN 12662-1, PN-EN 12662-2 and ASTM D 5452. The "Laboratories" tab ("PN-EN 12662-2") shows 10 laboratories: these 8 Polish ones and 2 Czech ones (tab query on labcoda.pl, 27.10.2026).

WHAT THE LABORATORIES TEST (database copy and PCA documents). All entries: contamination content, gravimetric method. Object: fatty acid methyl esters (FAME) as a liquid biofuel or biocomponent (AB 009, AB 079, AB 103, AB 484, AB 1668, AB 1679); "Liquid fuels" without further specification (AB 098, AB 387). Ranges: 5.0–27.0 mg/kg (AB 484, AB 1668, AB 1679), 5–27 mg/kg (AB 103), 5.0–30.0 mg/kg (AB 009), 6.0–30.0 mg/kg (AB 079); AB 098 and AB 387 give no range.

ALONGSIDE THIS STANDARD (database copy, 27.10.2026). Contamination content in entries with FAME in the object description is in the scopes of 9 Polish laboratories; part 1 of the standard (PN-EN 12662-1) is given in such entries by 6 of them (AB 009, AB 103, AB 1275, AB 297, AB 484, AB 773) — at all six with the object description "diesel fuel with FAME", i.e. within the scope of part 1.

WHERE A SEEMINGLY CORRECT RESULT IS EASY TO GET. First — choice of part: pure FAME (B100) is tested according to part 2, and diesel fuel and distillates with FAME up to 30 % (V/V) — according to part 1; the regulation on test methods for biofuels cites part 2 for FAME as a self-contained fuel and part 1 for diesel fuel with 20 % ester (B20). Second — working range 5–27 mg/kg: two laboratories declare an upper limit of 30 mg/kg (AB 009, AB 079), above the working range of this part of the standard; the requirement of 24 mg/kg lies within the working range. Third — viscosity: for FAME with a viscosity above 8 mm²/s at 20 °C or 5 mm²/s at 40 °C the method can be used, but without determined precision. Fourth — precision for conformity assessment: for FAME the regulation refers to Annex A of standard PN-EN 14214, not to the precision data of the method itself. Fifth — edition: before November 2024 pure FAME was tested according to PN-EN 12662:2014 (today withdrawn and replaced by both parts); a citation of the standard without the year in a scope does not tell which edition the laboratory uses.

WHAT WE DO NOT GIVE. The fragment of EN 12662-2:2024 we read comprises the title page, contents, foreword and introduction; we know the scope from the description in the iTeh catalogue and from the regulation. We do not give the reagents and materials (type and porosity of the filter, washing solvents), apparatus, mass of the test portion, drying and weighing conditions, the calculation formula or the repeatability and reproducibility values.

Method principle

A portion of pure FAME is filtered under vacuum through a previously weighed filter; the filter with the residue is washed, dried and weighed, and the total contamination (undissolved substances) is calculated from the increase in filter mass relative to the mass of the sample, in mg/kg (description of the method in Journal of Laws 2025 item 1341, part I point 16.1; working range 5–27 mg/kg according to EN 12662-2:2024). WE DO NOT GIVE details of the procedure.

Applications

• Pure fatty acid methyl esters (FAME, B100) — total contamination 5–27 mg/kg (EN 12662-2:2024, scope)
• FAME with a viscosity up to 8 mm²/s at 20 °C or 5 mm²/s at 40 °C (e.g. according to EN 14214); at higher viscosity — without determined precision
• Quality control of FAME as a self-contained fuel — requirement ≤ 24 mg/kg (Journal of Laws 2025 item 426), method cited in Journal of Laws 2025 item 1341
• In accreditation scopes: 8 Polish laboratories, gravimetric method; ranges 5–27 and 5–30 mg/kg

Key parameters

Standard

Standard number

PN-EN 12662-2:2024-11 (wersja polska i wersja angielska; wprowadza EN 12662-2:2024 [IDT])

Title (PL)

Ciekłe przetwory naftowe — Oznaczanie całkowitej zawartości zanieczyszczeń — Część 2: Estry metylowe kwasów tłuszczowych

Title (EN)

Liquid petroleum products — Determination of total contamination — Part 2: Fatty acid methyl esters

Step-by-step procedure

1. Preparation of containers and assembly

   Cleaning of sample containers and of the filtration assembly according to clause 7, preparation of the filter according to clause 10. WE DO NOT GIVE details.

2. Test portion

   Preparation of the portion of pure FAME according to 9.2; WE DO NOT GIVE the mass of the portion.

3. Filtration, washing, drying

   Vacuum filtration through a previously weighed filter, washing of the filter with the residue, drying (Journal of Laws 2025 item 1341, part I point 16.1).

4. Weighing and calculation

   Contamination content from the difference in filter masses relative to the mass of the sample, in mg/kg; assessment against ≤ 24 mg/kg for FAME as a self-contained fuel.

5. Report

   According to clause 15; when citing, give part 2 and the edition. PN-EN 12662-2:2024-11 — current (PKN card as of 27.10.2026).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• The standard warns that its use may involve hazardous materials, operations and equipment, and that the user establishes the safety measures (warning in the scope of the standard)
• TECHNICAL NOTE: pure FAME — part 2; diesel fuel with FAME up to 30 % (V/V) — part 1 (separate entry of this database)

Frequently asked questions