🌿 Calculation of dry matter of waste samples — Method A: drying a portion giving at least 0.5 g of residue at (105 ± 3) °C to constant mass (difference after a further hour not more than 0.5 % or 2 mg), at least two determinations; Method B: water content by direct Karl Fischer titration, liquids directly, solids after extraction with methanol; samples with more than 1 % (m/m) of dry residue or water, PN-EN 14346 (withdrawn)

Environment PN-EN 14346

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-EN 14346:2011 (Polish version), in full (our translation): “This European Standard specifies methods for the calculation of the dry matter of samples for which the results of performed analysis are to be calculated to the dry matter basis. Depending on the physical properties of the sample, the calculation is based on the determination of the dry residue (Method A) or on the determination of the water content (Method B). The standard applies to samples containing more than 1 % (m/m) of dry residue or more than 1 % (m/m) of water”. We read the text of the standard in the sample of SIST EN 14346:2007 (the text of EN 14346:2006 without changes) from the title page through the contents, foreword, introduction and Clauses 1–6 (the whole of Method A with calculation) up to and including 7.4.3 of Clause 7 (Method B — analysis of solid samples). Outside the sample remain the rest of 7.4.3, Clause 8 (performance characteristics), 9 (calculation of dry matter), 10 (test report) and Annexes A–C (additional validation data, azeotropic distillation with toluene, summary of requirements).

ACCORDING TO THE TEXT OF EN 14346:2006 (Clauses 1–6, 7.1–7.4.3). The standard was prepared by CEN/TC 292 “Characterization of waste” (secretariat NEN). Foreword: waste and sludge may contain toxic, reactive, flammable or infectious substances, and gases from samples may burst sealed bottles. Introduction: in waste analysis water is usually not considered part of the sample, and results are related to dry matter, calculated from the water content or the dry residue; the choice of method depends on the type of sample and its content of volatile substances other than water; after the validation study azeotropic distillation was replaced by Karl Fischer titration, and distillation is described in Annex B as informative. Scope (1): methods for calculating the dry matter of samples whose results are converted to dry matter — from the dry residue (A) or from the water content (B); applies to samples with more than 1 % (m/m) of dry residue or more than 1 % (m/m) of water. Normative reference (2): EN 15002 (preparation of test portions). Definitions (3), valid only for waste: dry residue wdr — mass fraction remaining after drying at 105 °C according to this standard; water content ww — mass fraction of water determined by Karl Fischer titration according to this standard; dry matter wdm — mass fraction of the sample excluding water, in per cent, calculated from the dry residue or water content. Principle (4): depending on the type of sample (liquid, solid, multiphase) either water or dry residue is determined; multiphase samples are homogenized, and if this is not possible — phases are separated according to EN 15002 and analysed separately. Method A (4.2): drying to constant mass at (105 ± 3) °C; for solids and samples that become solid during drying; solids with volatile constituents that may affect the result are analysed by Method B. Method B (4.3): direct Karl Fischer titration with volumetric or coulometric detection; liquids are added directly to the cell, solids are extracted with methanol; usually for liquids and homogenized multiphase samples, for solids — when the “water content” is of interest or when volatiles would interfere with Method A. Sample preparation and storage (5): the standard does not specify sample preparation — the dry residue or water is determined on identical portions of the same sample as the actual analysis, prepared according to the standard of that analysis; storage may change the sample (uptake or release of water, carbon dioxide and other volatiles) — if the determination cannot be done in parallel with the analysis, samples are kept in airtight containers. Method A (6): dry matter is determined in parallel on an identical portion in order to convert the results of other analyses. Interferences (6.2): the sample may change during drying — alkaline samples absorb carbon dioxide, reducing substances absorb oxygen; volatile compounds evaporating at 105 °C are measured as water in this method; alkaline samples or samples susceptible to oxidation may be dried in nitrogen. Hazards (6.3): flammable or explosive gases may be released during drying. Equipment (6.4): thermostatically controlled drying system maintaining (105 ± 3) °C — oven, infrared or halogen lamp system; desiccator with active drying agent (e.g. silica gel); analytical balance accurate to 1 mg or better; evaporating dish or crucible of metal or ceramic, compatible with the type of waste. Procedure (6.5): dish at least 30 min at (105 ± 3) °C, cool in the desiccator, weigh to the nearest 1 mg (ma); weigh in enough sample for a residue of at least 0.5 g, weigh (mb); dry at (105 ± 3) °C until the residue appears dry, typically overnight; for sludges forming a cake, a glass rod is weighed with the dish and used to break the cake; after cooling weigh; the residue is regarded as constant when after a further hour of drying the mass does not differ from the previous one by more than 0.5 % or 2 mg (whichever is greater) — otherwise drying is repeated; if after three cycles the mass is still not constant, drying may be stopped (after at least 12 h) and the last weighing recorded in the report; for infrared and halogen lamp systems the manufacturer’s instructions apply and the technique is recorded in the report — techniques other than oven drying are allowed if comparability of results is proven. Calculation (6.6): wdr = (mc − ma) × f / (mb − ma), where f = 100 for the result in per cent and f = 1000 for g/kg; at least two determinations, the mean is reported. Method B — interferences (7.1): among others peroxides, oxides, hydroxides, ammonia, carbonates and hydrogen carbonates, disulfites, nitrite, sulfite, thiosulfate, hydrazine, iron(II), copper(I), tin(II), silanols, arsenite, arsenate, selenite, tellurite, phenols, boron compounds, aldehydes, acetone and other reactive ketones may interfere, especially all reducing and oxidizing agents; in case of doubt the result can be verified by azeotropic distillation (Annex B); extraction with methanol reduces most interferences. Reagents (7.2): Karl Fischer reagent recommended by the supplier of the system; methanol with not more than 0.005 % (m/m) water; toluene, if necessary to dissolve the sample. Equipment (7.3): Karl Fischer titration apparatus, shaker, weighing pipette, 250 ml conical flasks with ground glass neck. Equivalence factor (7.4.1): the cell with methanol is titrated to the end point, approx. 80 mg of water is added with a weighing pipette with an accuracy of 0.1 % and titrated; F = W / V1 in mg water per ml; it is determined weekly (other standards with known water content may be used instead of water), and with coulometric detection no titer adjustment is needed. Liquids (7.4.2): to the pre-titrated methanol a suitable amount of sample is added with an accuracy of 0.1 % (with water below 10 % — approx. 1 g) and the titrant volume is noted; water content is calculated by formula (3), and dry matter by formula (6). Solids (7.4.3): approx. 10 g of sample with an accuracy of 0.1 % into a conical flask, 50.0 ml of methanol, 10 min shaking, and into the pre-titrated cell a suitable volume of extract (with water below 5 % — approx. 10 ml).

STATUS (catalogue cards as of 03.10.2026). The card of PN-EN 14346:2011 (Polish version, published 28-11-2011, 21 pages, price group L) has the header “Withdrawn”: withdrawal date 08-08-2018; Health, Environment and Medicine Sector, KT 216 Waste, ICS 13.030.01, “Introduces: EN 14346:2006 [IDT]”, “Supersedes: PN-EN 14346:2007 — English version”; the card has no “Replaced by” field. The card of PN-EN 14346:2007 (English version) — “Withdrawn” 28-11-2011, “Replaced by: PN-EN 14346:2011 — Polish version”. The PKN search (term “PN-EN 14346”, 03.10.2026) shows no other editions — PKN indicates no successor. In the iTeh catalogue (read 03.10.2026) the Slovenian adoption SIST EN 14346:2007 has the status “Withdrawn” dated 09.04.2019 and the entry “Replaced By: SIST EN 15934:2012” (sludge, treated biowaste, soil and waste — calculation of dry matter after determination of dry residue or water content). At PKN the cards of PN-EN 14346 do not list PN-EN 15934; PN-EN 15934:2013-02 itself (both language versions, entry on PN-EN 15934) has the header “Withdrawn” dated 04-03-2026 and “Replaced by: PN-EN ISO 11465:2026-03 — English version” — the chain of successors thus leads today to PN-EN ISO 11465:2026-03, whose text we did not read.

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, load up to 17.09.2026, read 03.10.2026). The number 14346 appears in 6 records at 5 laboratories: AB 213, AB 418, AB 550, AB 869, AB 1160. In the current scopes on the PCA website (read 03.10.2026, issues from 26.01.2026 to 22.09.2026) all except AB 550 give “PN-EN 14346:2011” — AB 869 and AB 1160 with the note “method A”, AB 418 “excluding item 7”, i.e. without Method B; AB 550 gives the designation alone without year. The “Laboratories” tab (“PN-EN 14346”) shows the same 5 laboratories; checked with the tab query on the production server labcoda.pl on 03.10.2026.

WHAT THE LABORATORIES TEST (PCA items). Waste with codes (AB 213 — construction waste of group 17, AB 550, AB 869, AB 1160), solid recovered fuels (AB 550) and construction materials — sand, aggregate, slag (AB 418). Item names: “Dry matter”, “Dry matter content”, “Dry matter / Water content” (AB 418). Technique in all items: gravimetric method — i.e. Method A; Karl Fischer titration (Method B) with this reference does not appear in the scopes. Ranges: (0.10–99.0) % (AB 213 — one item covers waste according to PN-EN 14346:2011 and soil and ground according to PN-EN 15934:2013-02 — also withdrawn, 04-03-2026), (1.0–98.0) % (AB 418), (1.0–99.5) % (AB 1160), (1.0–20) % (AB 869); AB 550 gives no range. The lower limit of this AB 213 item — 0.10 % — lies below the threshold of Clause 1 (more than 1 % dry residue); the scope does not show whether it concerns waste or soil.

WHERE A SEEMINGLY CORRECT RESULT IS EASY. At storage: a sample kept in a non-airtight container loses or gains water and carbon dioxide, and dry matter determined later does not correspond to the portion on which the analysis was done (5). At drying: volatile compounds evaporating at 105 °C count as water — in waste with solvents or fuels dry matter is too low and results of other analyses converted to it too high; therefore such samples are analysed by Method B (4.2, 6.2); alkaline samples absorb CO2, reducing ones oxygen — the mass after drying increases (6.2); a cake on sludge hinders even drying (6.5). At weighing: “constant mass” has a strict criterion (0.5 % or 2 mg after a further hour) — a single weighing after a night does not meet it; the portion must give at least 0.5 g of residue (6.5). With Method B: in Karl Fischer titration among others carbonates, aldehydes, acetone and other reactive ketones may interfere, especially all reducing and oxidizing agents; the result can be verified by azeotropic distillation (7.1). At calculation: dry matter is not an end in itself — it is a component of the conversion of results of other analyses, so it must come from an identical portion of the same sample, prepared according to the standard of that analysis (5, 6.1); in Method A dry matter is directly the dry residue, in Method B — a result calculated from the water content.

WHAT WE DO NOT GIVE. We did not read Clauses 8–10 and the annexes, so we do not give formulas (4)–(6) or the calculation of dry matter from water content in Method B, validation data and report requirements beyond the statements of 6.5. We did not read the texts of PN-EN 15934 and PN-EN ISO 11465:2026-03 for this entry and do not compare the standards.

Method principle

The dry matter of a waste sample is calculated from one of two measurements: in Method A a portion is dried at (105 ± 3) °C to constant mass, and the ratio of the mass of the residue to the mass of the sample gives the dry residue; in Method B water is determined by Karl Fischer titration (liquid directly, solid in a methanol extract), and dry matter is its complement. The result is used to convert results of other analyses of the same sample to dry matter.

Applications

• Solid, liquid and multiphase waste with more than 1 % (m/m) of dry residue or water — conversion of analysis results to dry matter (Clause 1, introduction)
• Method A — solids and samples that solidify on drying; Method B — liquids, multiphase samples and solids with volatile constituents (4.2, 4.3)
• Construction and other coded waste, solid recovered fuels, construction materials — in the accreditation scopes of 5 laboratories at PCA, all by the gravimetric method

Key parameters

Standard

Standard number

PN-EN 14346:2011

Title (PL)

Charakteryzowanie odpadów — Obliczanie suchej masy na podstawie oznaczania suchej pozostałości lub zawartości wody

Title (EN)

Characterization of waste — Calculation of dry matter by determination of dry residue or water content

Step-by-step procedure

1. Choice of method and portion

   Solids — Method A; liquids, multiphase samples and samples with volatile constituents — Method B; portion identical with that of the actual analysis. PN-EN 14346:2011 withdrawn 08-08-2018 (PKN catalogue card as of 03.10.2026).

2. Method A — preparation of the dish

   Dish ≥ 30 min at (105 ± 3) °C, cool in the desiccator, weigh (ma); weigh in the sample so that the residue is ≥ 0.5 g (mb).

3. Method A — drying to constant mass

   Dry at (105 ± 3) °C, typically overnight; cool, weigh; repeat after 1 h until change ≤ 0.5 % or ≤ 2 mg; break the cake with the weighed glass rod.

4. Method A — calculation

   wdr = (mc − ma) × f / (mb − ma), in % or g/kg; mean of at least two determinations.

5. Method B — Karl Fischer

   Weekly factor F (approx. 80 mg water); liquid approx. 1 g directly into the cell; solid approx. 10 g + 50.0 ml methanol, 10 min shaking, portion of the extract. Calculation of dry matter (Clause 9) outside the sample read.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Flammable or explosive gases may be released during drying (6.3)
• Waste and sludge may contain toxic, reactive, flammable or infectious substances; gases from samples may burst sealed bottles (foreword)
• Methanol and toluene are flammable and toxic; Karl Fischer reagent — according to the supplier’s safety data sheet

Frequently asked questions