🌿 Determination of particle size distribution in mineral soil material by sieving and sedimentation — particles retained on the 2 mm sieve are determined by dry sieving (sample mass depending on the largest particles, sieves checked against master sieves), particles of 2–0,063 mm by wet and dry sieving, and particles below 0,063 mm by sedimentation with the pipette method (preferred) or the hydrometer method of Annex B, after removal of organic matter and salts and with addition of a dispersing agent; sampling times from Stokes’ law at a particle density of 2,65 Mg/m³; fraction proportions are determined only by weighing and presented as a cumulative curve, PN-ISO 11277

Environment PN-ISO 11277

Overview

WHAT THE STANDARD COVERS. We read the text of the standard in the iTeh sample of SIST ISO 11277:2006, i.e. ISO 11277:1998 (English text, first edition of 15.05.1998): title page, contents, foreword, introduction, Clauses 1–7 and Clause 8 up to 8.2.1 (sampling pipette) — the sample ends on page 6. We do not read the rest of Clause 8 (apparatus and procedure for wet sieving and sedimentation, removal of organic matter, salts, iron oxides and carbonates, calculation), precision (9), the test report (10) or Annexes A (non-dried material), B (hydrometer method after removal of organic matter) and C (bibliography); we know their titles from the contents.

ACCORDING TO THE TEXT OF ISO 11277:1998. The standard was prepared by ISO/TC 190 “Soil quality”, Subcommittee SC 5 “Physical methods”; Annexes A and B are normative, C is informative. Introduction: the result is affected by organic matter, soluble salts, cementing agents (especially iron compounds), carbonates and sulfates; some soils change their behaviour on drying so much that the particle size distribution of dried material bears little relation to that of undried material (soils rich in organic matter, from young volcanic deposits, some tropical soils, cohesive soils), and others disperse poorly despite a high clay content; the choice of procedure depends on field information, which the laboratory must receive; the whole standard must be read before starting work. Scope (1): a basic method for a wide range of mineral soil materials, including the mineral fraction of organic soils, with procedures for atypical soils; developed mainly for environmental sciences — for geotechnical investigations specialist advice may be needed; the aim is to determine enough fractions to construct a reliable distribution curve; it does not apply to organic soil constituents; chemical and mechanical treatment may break down weakly cemented particles — if this is undesirable, the standard should not be used. References (2): ISO 565:1990 (sieve apertures), ISO 3310-1 and -2:1990 (test sieves), ISO 3696:1987 (water), ISO 11464:1994 (sample pretreatment). Terminology (3.1): common names of fractions (gravel, coarse sand, silt, etc.) must not be used when describing results — instead “passing the 20 mm sieve”, “below 0,063 mm equivalent diameter”; the only generally agreed limit is clay — below 0,002 mm equivalent diameter; if names are necessary, they must be defined; the word “texture” and sieve mesh numbers must not be used in the report. Principle (4): the distribution is determined by a combination of sieving and sedimentation, starting from air-dried soil (method for undried soil — Annex A); particles retained on the 2 mm sieve — dry sieving; particles passing 2 mm but retained on 0,063 mm — wet and dry sieving; particles passing 0,063 mm — sedimentation; the pipette method is preferred, the hydrometer method is in Annex B; fraction proportions only from masses obtained by weighing — any other way (e.g. interaction with electromagnetic radiation or an electric field) excludes claiming conformity with the standard; both sedimentation methods assume Stokes’ law and its limitations (rigid smooth spheres, laminar flow — Reynolds number below about 0,2, giving an upper limit slightly above 0,06 mm, dilute suspension, no interactions, terminal velocity, uniform density); t = 18ηh/[(ρs − ρw)g dp²], with ρs = 2,65 Mg/m³ (quartz), ρw = 1,00 Mg/m³ (water with a small amount of dispersant, within the permitted temperature range), g = 981 cm/s²; conversion of sampling times into minutes and hours is recommended (Table 3). Field sampling (5): sample mass representative of the distribution, minimum masses in Table 1. Pretreatment (6): according to ISO 11464; if the result concerns only the < 2 mm fraction, the sample may be taken from material passing the 2 mm sieve. Dry sieving (7): maximum mass on a sieve in Table 2 (e.g. 20 mm sieve of 450 mm diameter — 4 kg; 2 mm of 200 mm diameter — 0,2 kg; 0,063 mm — 0,025 kg), excess is divided and re-sieved; the minimum sample mass in Table 1 depends on the largest particles making up more than 10 % of the soil (e.g. 63 mm — 50 kg, 20 mm — 2 kg, 2 mm or less — 0,1 kg); sieves according to ISO 565, checked monthly against a set of master sieves (reference materials, microscopy), tolerances according to ISO 3310-1 and -2, non-conforming sieves rejected and recorded; weekly inspection with regular use; sieves with round apertures are not used; balance ± 0,5 g; mechanical shaker (usually at least 10 min); the dry sample (m1) is sieved on the 20 mm sieve with brushing, coarse fractions on a set of sieves, material < 20 mm (m2 or a part m3) on a set down to 2 mm until passage stops; sum of fractions within 1 % of m2 or m3, otherwise check sieves for damage; equipment performance checked monthly with a reference material (e.g. glass beads); result — table of mass proportions to two significant figures and a cumulative curve. Wet sieving and sedimentation (8.1): for material < 2 mm down to < 0,002 mm; removal of organic matter and salts (especially sparingly soluble ones such as gypsum) and addition of a dispersant are required — omitting them invalidates the application of the standard; removal of iron oxides and carbonates is sometimes used and must be recorded in the report; gravity sedimentation gives the total amount < 0,002 mm but does not allow it to be divided reliably, because particles below about 0,001 mm stay in suspension by Brownian motion. Apparatus (8.2): one operator can handle up to 36 samples per batch; pipette of at least 10 ml in a stand lowering it to a fixed depth (in practice 50 ml is adequate, routinely 25 ml; a smaller one suffices with about 10 % of the < 0,063 mm fraction, below that a larger one is more accurate).

STATUS (as of 03.10.2026). In the PKN search (term “11277”, 03.10.2026) the only result is PN-ISO 11277:2005 (Polish version, “Introduces: ISO 11277:1998 [IDT], ISO 11277:1998/Cor 1:2002 [IDT]”) with the note “Withdrawn”. Card: publication date 05.05.2005, withdrawal date 28.11.2022, 45 pages, KT 192 General and Soil Physics, ICS 13.080.20; the card does not indicate a replacing standard, and the search returns no standard introducing a newer ISO edition. In the iTeh catalogue (read 03.10.2026) ISO 11277:1998 has the status “Withdrawn”, stage 95.99, with the note “Revised: ISO 11277:2009”; ISO 11277:2020 — status “Published”, stage 90.92 (international standard to be revised), with the draft ISO/FDIS 11277. We have not read the 2009 and 2020 editions.

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 11277 appears in 5 records at 3 laboratories: AB 005 (2), AB 418 (2), AB 740. In the current PCA documents (read 03.10.2026; AB 005 issue No. 29 of 18.12.2025, AB 418 issue No. 37 of 26.01.2026, AB 740 issue No. 19 of 02.06.2026) the number appears in 4 lines at the same 3 laboratories (the two AB 418 records — sieve and hydrometer method — share one line with the reference in the document); in each document the number of page markers equals the number of PDF pages, without repetitions; a search of all PCA documents downloaded from the BIP on 03.10.2026 found no laboratories outside the database copy. The form is always “PN-ISO 11277:2005” — all three laboratories cite the edition withdrawn in PKN. None of these items is suspended. The “Laboratories” tab (term “PN-ISO 11277”) shows all 3 laboratories — checked by a tab query on the labcoda.pl production server on 03.10.2026.

WHAT THE LABORATORIES TEST (items in PCA). Object: soils and soil (AB 005, two lines), soil, soils (AB 418), soil (AB 740). Characteristic and range: particle size distribution for particles of (2,0–8,0) mm, range (1–90) %, sieve-gravimetric method (AB 005); distribution in the range (0,063–20) mm, (10–100) %, sieve method, and (0,002–2,0) mm, (0,5–10) %, hydrometer method (AB 418); particle size distribution, (0,01–100) %, sedimentation (pipette) method (AB 740).

ALONGSIDE THIS STANDARD (database copy, records with “gleb” in the object and “granulometr” or “uziarnien” in the test description — 32 records at 20 laboratories, read 03.10.2026). Besides PN-ISO 11277, 3 laboratories each cite ISO 13320 (laser diffraction; AB 005, AB 300, AB 550 — in PCA “ISO 13320:2020”), PN-R-04032 (AB 213, AB 313, AB 945 — “PN-R-04032:1998”) and PN-EN ISO 17892-4 (AB 106, AB 213, AB 313 — “PN-EN ISO 17892-4:2017-01”), all present in the current PCA documents; 14 laboratories use in-house procedures (PB) for this characteristic.

WHERE AN APPARENTLY CORRECT RESULT IS EASY TO GET. With the status: all three laboratories cite PN-ISO 11277:2005, withdrawn in PKN on 28.11.2022 without an indicated successor, and ISO 11277:1998 was revised in 2009. With the measurement principle: fraction proportions only from weighing — a result from laser diffraction or another method does not conform to this standard (4), and ISO 13320 stands alongside it as a separate document. With pretreatment: omitting the removal of organic matter and salts or the dispersant invalidates the application of the standard (8.1); removal of iron oxides and carbonates must be recorded in the report; drying changes the distribution in some soils — Annex A covers them (introduction, 4). With the clay fraction: sedimentation does not reliably subdivide the < 0,002 mm fraction (8.1). With sieving: the minimum sample mass grows with particle size (Table 1), and overloading sieves lowers the result (Table 2); the sum of fractions must agree within 1 % (7.3). With the description of the result: no common fraction names, no word “texture” and no mesh numbers (3.1). With the application: the standard is environmental in character; AB 005 and AB 418 also apply it to soils for construction (“grunty”), and for geotechnical investigations the standard recommends specialist advice (1).

WHAT WE DO NOT GIVE. We do not quote the procedure for wet sieving and sedimentation, the removal of organic matter and salts, calculations, precision data, the test report or Annexes A–C — they lie outside the sample. We have not read ISO 11277:2009 or ISO 11277:2020.

Method principle

Particles retained on the 2 mm sieve are determined by dry sieving, the 2–0,063 mm fraction by wet and dry sieving, and particles below 0,063 mm by sedimentation (preferably the pipette method, alternatively the hydrometer method) after removal of organic matter and salts and with addition of a dispersant. Sampling times follow from Stokes’ law at a particle density of 2,65 Mg/m³; fraction proportions are determined only by weighing and presented as a continuous cumulative curve.

Applications

• Particle size distribution of mineral soil materials, including the mineral fraction of organic soils, mainly in environmental sciences (1)
• Atypical soils — procedures for undried material (Annex A) and the hydrometer method (Annex B) (4)
• Soil and soils for construction — items in the accreditation scopes of 3 laboratories in PCA (sieve, hydrometer and pipette methods)

Key parameters

Standard

Standard number

PN-ISO 11277:2005

Title (PL)

Jakość gleby — Oznaczanie składu granulometrycznego w mineralnym materiale glebowym — Metoda sitowa i sedymentacyjna

Title (EN)

Soil quality — Determination of particle size distribution in mineral soil material — Method by sieving and sedimentation

Step-by-step procedure

1. Sample

   Mass from Table 1, pretreatment according to ISO 11464; field information on the soil type (5, 6). PN-ISO 11277:2005 withdrawn in PKN on 28.11.2022 (03.10.2026).

2. Dry sieving

   20 mm sieve and set of sieves down to 2 mm, without overloading (Table 2), sum within 1 % (7).

3. Treatment of the < 2 mm fraction

   Removal of organic matter and salts, dispersant; possible removal of iron oxides and carbonates — recorded (8.1).

4. Wet sieving and sedimentation

   2–0,063 mm on sieves; < 0,063 mm by the pipette method at times from Stokes’ law (4, 8; further details outside the sample).

5. Result

   Mass proportions of fractions from weighing, two significant figures, cumulative curve; no common names or “texture” (3.1, 7.4).

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• The standard draws attention to known hazards — work only by trained persons under supervision (introduction)
• Reagents for removing organic matter and salts — according to the safety requirements for each substance

Frequently asked questions