⛏️ Determination of the particle density of filler by the pyknometer method — two samples of the 0/0.125 mm fraction dried at 110 °C (approx. 25 g each) in 50 ml pyknometers are covered with liquid, de-aerated for at least 30 min at a pressure below 3.0 kPa, topped up and thermostatted for 60 min in a 25 °C bath; density = mass of filler / (volume of the pyknometer − volume of liquid), mean of two determinations rounded to 0.01 Mg/m3, PN-EN 1097-7

Construction PN-EN 1097-7

Overview

WHAT THE STANDARD COVERS. The scope on the PKN catalogue card of PN-EN 1097-7:2023-04 (English version) begins with the words (our translation): “This document specifies the reference method used for type testing and in case of dispute for determining the particle density of filler by means of a pyknometer. For other purposes, in particular factory production control, other methods may be used provided that a correlation between them and the reference method has been established” — it then repeats the note and warning of Clause 1. We read the text of the standard in the sample of SIST EN 1097-7:2023 (the text of EN 1097-7:2022 without changes) from the title page through the contents, European foreword and Clauses 1–8 up to and including the middle of Clause 9 (formula 1 and the repetition rule); we read the formula from the page image, because the text extraction scrambled it. Outside the sample remain the rest of Clause 9 (when two of three results are within the 0.025 Mg/m3 limit), Clause 10 (test report) and the normative Annexes A (determination of the pyknometer volume) and B (density of the liquid).

ACCORDING TO THE TEXT OF EN 1097-7:2022 (Clauses 1–9). The standard was prepared by CEN/TC 154 “Aggregates” (secretariat BSI) under a standardization request of the European Commission; it superseded EN 1097-7:2008. Technical changes from the 2008 edition according to the foreword (selection): a reference to the methods for aggregates (EN 1097-6) was added to the scope; the definitions were aligned with EN 1097-6 and a definition of the fraction di/Di was added; low-viscosity white mineral oils were added to the examples of liquids; the required accuracy of the water bath temperature was reduced from (25.0 ± 0.1) °C to (25.0 ± 3.0) °C or (25.0 ± 0.5) °C depending on the liquid; the balance accuracy for determining the pyknometer volume was reduced from 0.0001 g to 0.001 g, because water is always used for this; the masses of test portions and samples were changed and a change in the amount of filler (ratio of filler to liquid) was permitted, to reduce the influence of temperature on the liquid density; the number of samples was reduced from three to two if two results differ by less than 0.025 Mg/m3; the liquid density was moved to optional data in the test report; Annex A was named “determination of the pyknometer volume” and a description of vacuum de-aeration was added; Annex C with precision data was deleted “because their origin can no longer be established”, and the note on precision in Clause 9 was changed. Scope (1): reference method for type testing and disputes — determination of the particle density of filler with a pyknometer; for other purposes, in particular factory production control, other methods are permitted once their relationship to the reference method has been established; methods for aggregate particles — EN 1097-6; warning: liquids, dust, noise and weights. References (2): EN 932-2:1999 (reducing laboratory samples), EN 932-5 (common equipment and calibration), ISO 3507 (pyknometers). Definitions (3): constant mass — successive weighings after drying at least 1 h apart not differing by more than 0.1 % (often achieved after drying at (110 ± 5) °C for a time established by the laboratory); particle density of filler ρf — mass of the dried filler sample divided by the volume it occupies in the liquid, including closed internal pores, excluding liquid in pores accessible to the liquid (corresponds to the “oven-dried particle density” of EN 1097-6); filler — aggregate most of which passes the 0.063 mm sieve, added to construction materials to provide certain properties; fraction di/Di. Principle (4): a pyknometer of known volume with the sample is topped up with a liquid of known density; the volume of the liquid is its mass divided by its density, and the volume of the sample — the pyknometer volume minus the volume of the liquid. Materials (5): a liquid in which the filler does not dissolve and with which it does not react — water, denatured ethanol, redistilled kerosene, low-viscosity white mineral oils or toluene may be suitable; demineralized water boiled and cooled, and acetone — for determining the pyknometer volume. Apparatus (6): pyknometer of 50 ml nominal capacity according to ISO 3507, with a stopper concave on the underside and a thick-walled capillary ground flat; water bath (25.0 ± 3.0) °C with water or (25.0 ± 0.5) °C with other liquids; balance accurate to 0.001 g (water; pyknometer volume) and 0.0001 g (other liquids; liquid density); drying oven (110 ± 5) °C; desiccator; vacuum desiccator; vacuum pump below 3.0 kPa; spatula; 0.125 mm sieve. Preparation (7): laboratory sample with at least 100 g of the 0/0.125 mm fraction, reduced according to EN 932-2 to a test portion of two samples of approx. 25 g dry mass each (the amount may be changed to optimize the ratio of filler and liquid volumes); drying at (110 ± 5) °C to constant mass and at least 90 min of cooling in the desiccator; break up lumps with the spatula; dry-sieve through the 0.125 mm sieve and keep the passing fraction; two samples according to EN 932-2:1999, Clause 11. Procedure (8): two determinations, pyknometers of known volume (Annex A), liquid of known density (Annex B), all weighings to the nearest 0.001 g; weigh the clean, dry pyknometer with stopper (m0); put in the sample occupying roughly half the volume and weigh (m1); very carefully add liquid until it covers the sample, letting it soak through the filler; the mass of filler (m1 − m0) may be kept constant for successive measurements of the same filler; stopper, evacuate in the vacuum desiccator below 3.0 kPa within approx. 5 min and hold for at least 30 min; after pressure equalization top up with liquid, place the pyknometer without stopper in the bath at (25 ± 3.0) °C or (25 ± 0.5) °C so that it protrudes 2–3 mm above the water; after 60 min insert the stopper (liquid flows out through the capillary), dry the top of the capillary, take out, cool quickly under cold running water (so that the liquid does not flow out of the capillary from the warmth of the hands), dry and weigh (m2). Calculation (9): ρf = (m1 − m0) / [V − (m2 − m1) / ρl], where ρf — particle density of the filler at 25 °C in Mg/m3, V — pyknometer volume in ml (Annex A), ρl — liquid density at 25 °C in Mg/m3 (Annex B); result — mean of two determinations rounded to 0.01 Mg/m3; if two results differ by more than 0.025 Mg/m3, a third determination is carried out.

STATUS (catalogue cards as of 03.10.2026). The card of PN-EN 1097-7:2023-04 (English version, published 11-04-2023, 16 pages, price group H) has no “Withdrawn” header: Building and Construction Sector, KT 108 Aggregates and Building Stone, ICS 91.100.15, “Introduces: EN 1097-7:2022 [IDT]”, “Supersedes: PN-EN 1097-7:2008 — English version”. The card of PN-EN 1097-7:2008 (English version) — “Withdrawn” 11-04-2023, “Replaced by: PN-EN 1097-7:2023-04”; it itself superseded PN-EN 1097-7:2001 (Polish version). What changed for the result in the transition from 2008 to 2023: two determinations instead of three (with agreement within 0.025 Mg/m3), a wider bath temperature tolerance with water (± 3.0 °C instead of ± 0.1 °C) and variable amounts of filler — according to the foreword. In the iTeh catalogue (read 03.10.2026) SIST EN 1097-7:2023 has the status “Published”.

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 1097-7 appears in 8 records at 6 laboratories: AB 054, AB 550, AB 687, AB 937, AB 1269, AB 1344. In the current scopes on the PCA website (read 03.10.2026, issues from 18.12.2025 to 22.09.2026) AB 550, AB 687 and AB 1344 give “PN-EN 1097-7:2023-04”, AB 937 and AB 1269 — the designation alone without year (flexible scope, “Fillers E”), and AB 054 — in one of three items with the year 2023-04, in two without year. The “Laboratories” tab (“PN-EN 1097-7”) shows the same 6 laboratories; checked with the tab query on the production server labcoda.pl on 03.10.2026.

WHAT THE LABORATORIES TEST (PCA items). Fillers (AB 937, AB 1269 — flexible scope; AB 1344), aggregates, fly ash and filler aggregates (AB 687), fly ash (AB 550) and at AB 054 — fillers (ash, slag-ash, cement, sand), fly ash and wastes with codes 19 01 12, 19 01 14 and from group 10 01. Items: “Density of filler”, “Particle density” (in several spellings), “Density”; pyknometer method. Ranges: (1.50–3.00) Mg/m3 (AB 550 and two items of AB 054) and (1.5–4.0) Mg/m3 (AB 054, fillers); the others give no range. For cement, ashes and wastes, which AB 054 and AB 550 test by this standard, the text gives no separate guidance — it requires only a liquid in which the material does not dissolve and with which it does not react (5.1).

WHERE A SEEMINGLY CORRECT RESULT IS EASY. At the liquid: the standard requires a liquid in which the filler does not dissolve and with which it does not react, and gives only examples (5.1) — checking this condition for the material tested is up to the laboratory. At de-aeration: air trapped between the particles increases the apparent volume of the sample and lowers the density — hence the vacuum below 3.0 kPa for at least 30 min and careful addition of liquid (8). At temperature: the liquid density ρl refers to 25 °C — with liquids other than water the bath tolerance is only ± 0.5 °C, and the warmth of the hands pushes liquid out of the capillary, which is why the pyknometer is cooled quickly before weighing (6.3, 8). At calculation: ρf is not a direct measurement — its components are the three weighings of this method (m0, m1, m2) and the pyknometer volume V and the liquid density ρl, determined separately according to the normative Annexes A and B; an error in V or ρl passes into every result from the given pyknometer and liquid. At repetitions: two results differing by more than 0.025 Mg/m3 require a third determination (9).

WHAT WE DO NOT GIVE. We did not read the rest of Clause 9, Clause 10 and Annexes A–B, so we do not give how the decision is made with three results, the procedure for determining the pyknometer volume and the liquid density, or the test report requirements. According to the foreword the standard no longer contains precision data (Annex C deleted).

Method principle

The volume of irregular filler particles is determined by liquid displacement: a pyknometer of known volume with a weighed sample, de-aerated under vacuum, is topped up at 25 °C with a liquid of known density; the volume of the added liquid is its mass divided by its density, and the volume of the sample — the pyknometer volume minus the volume of the liquid. The particle density is the mass of the dried sample divided by this volume.

Applications

• Fillers (aggregate mostly below 0.063 mm) — particle density by the reference method in type testing and disputes (Clause 1)
• Factory production control — other methods once their relationship to the reference method has been established (Clause 1)
• Fillers, filler aggregates, fly ash, and at one laboratory also cement, sand and furnace wastes — in the accreditation scopes of 6 laboratories at PCA

Key parameters

Standard

Standard number

PN-EN 1097-7:2023-04

Title (PL)

Badania mechanicznych i fizycznych właściwości kruszyw — Część 7: Oznaczanie gęstości wypełniacza — Metoda piknometryczna

Title (EN)

Tests for mechanical and physical properties of aggregates — Part 7: Determination of the particle density of filler — Pyknometer method

Step-by-step procedure

1. Sample preparation

   Reduce the sample (EN 932-2), dry at (110 ± 5) °C to constant mass, cool ≥ 90 min, break up lumps, sieve through 0.125 mm; two samples of approx. 25 g. PN-EN 1097-7:2023-04 current (PKN catalogue card as of 03.10.2026).

2. Weighing and covering

   Pyknometer with stopper (m0); with the sample occupying approx. half the volume (m1); very carefully add liquid to cover the sample.

3. De-aeration

   Stoppered pyknometer in the vacuum desiccator: < 3.0 kPa within approx. 5 min, hold ≥ 30 min.

4. Topping up and thermostatting

   Top up with liquid, 60 min in the 25 °C bath (protruding 2–3 mm), insert the stopper, dry the capillary, cool quickly, dry, weigh (m2).

5. Calculation

   ρf = (m1 − m0) / [V − (m2 − m1) / ρl]; mean of two, to 0.01 Mg/m3; difference > 0.025 Mg/m3 — third determination.

Required equipment and apparatus

Reagents, media and consumables

Health and safety (OHS)

• Use of the standard may involve hazardous materials, operations and equipment — liquids, dust, noise, lifting of weights (warning in Clause 1)
• Toluene, denatured ethanol, kerosene and acetone are flammable and harmful — work in a fume hood; vacuum desiccator — implosion guard

Frequently asked questions