This document (prEN 17732:2025) has been prepared by Technical Committee CEN/TC 223 “Soil improvers and growing media”, the secretariat of which is held by NEN.

This document is currently submitted to the CEN Enquiry.

This document will supersede CEN/TS 17732:2022.

prEN 17732:2025 includes the following significant technical changes with respect to CEN/TS 17732:2022:

— Redundant information has been removed from the Introduction;

— Several definitions have been updated in Clause 3, Terms and definitions.

This document has been prepared under a Standardization Request given to CEN by the European Commission and the European Free Trade Association.

Introduction

Standards requested in Standardization Request M/564 related to soil improvers and growing media use common terminology. For ease of reference, to simplify standardization work and to avoid unnecessary repetitions such common terminology is included in this document. In this way, any document where the relevant terminology is used could refer to this document.

1.0 Scope

This document specifies terminology for soil improvers and growing media.

Annex A contains an overview of all terms defined in this document in alphabetical order.

2.0 Normative references

There are no normative references in this document.

3.0 Terms and definitions

For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp/

— IEC Electropedia: available at https://www.electropedia.org/

3.1 General terms

3.1.1

additional labelling

information which can be shown on the package, label or on the accompanying documents

3.1.2

container

receptacle or vessel in which material is delivered, including a lorry, ship, boat and packaging

3.1.3

intended use

application of a product, process or service in accordance with information provided by the supplier

3.1.4

labelling requirements

information which is shown on the package, label or on the accompanying documents

3.1.5

package

container and materials contained therein which are delivered and where the packaging remains with the material after delivery

Note 1 to entry: A package may be a loose-filled sack, a big bale or a compressed block in packaging.

3.1.6

strike

transparent sheet of flat material, for instance toughened glass or acrylic glass which is easily large enough to cover the top of the measuring cylinder

Note 1 to entry: Used to calibrate measuring cylinder.

3.1.7

user

anybody applying the product, including professional and non-professional (amateur) persons

3.1.1 Terms relating to products

3.2.1

growing medium

material, other than soil in situ, in which plants or mushrooms are grown

3.2.2

growing medium component

material which is suitable as an ingredient of growing media

3.2.3

pre-shaped growing medium

solid, regular shaped, stable growing medium, which is ready for use as a growing medium, where the dimensions are stable, including mineral wool and polyurethane products

3.2.4

soil improver

material added to soil in situ primarily to maintain, improve or protect the physical or chemical properties, the structure or the biological activity of the soil

3.2.5

soil improver component

material which is suitable as an ingredient of soil improvers

3.1.2 Terms relating to components

3.3.1

ash

residual mineral matter remaining after the destruction of organic matter/material by controlled burning

Note 1 to entry: Such residues may be used as fertilizers, for example, plant ash and animal ash, containing mainly potassium salts and phosphates.

3.3.2

biochar

porous, carbonaceous material that is produced by pyrolysis of organic material

3.3.3

coir

fibrous husk (mesocarp) of the coconut (Cocos nucifera), underlying the smooth outermost layer (exocarp), surrounding the hard woody layer (endocarp)

Note 1 to entry: Coir consists of fibres and pith.

3.3.4

compost

solid particulate material that is the result of a thermophilic aerobic composting of biodegradable matter by microorganisms, which has been sanitised and stabilised

3.3.5

digestate

solid or liquid product that is the result of anaerobic digestion of biodegradable materials by microorganisms

3.3.6

digestate other than fresh crop digestate

component material designated as CMC 5

Note 1 to entry: Further information can be found in the Regulation (EU) 2019/1009.

3.3.7

fresh crop digestate

component material designated as CMC 4

Note 1 to entry: Further information can be found in the Regulation (EU) 2019/1009.

3.3.8

industrial sludge

semi‐liquid residue or slurry that remains after the treatment of industrial water and wastewater

3.3.9

leonardite

soft waxy, black or brown, shiny, vitreous mineraloid

Note 1 to entry: Leonardite is an oxidation product of lignite, associated with near-surface mining.

3.3.10

lignite

fossil, soft, brown, combustible, sedimentary rock formed from naturally compressed organic material in the absence of oxygen (coalification)

Note 1 to entry: Lignite is often referred to as brown coal.

3.3.11

organic material

material of plant and/or animal origin

3.3.12

peat

weakly to strongly decomposed (humified) plant material consisting of non-fossil organic matter that has sedentarily accumulated in a water-saturated environment (mire) in the absence of oxygen

3.3.13

Sphagnum

plant genus of peat mosses

Note 1 to entry: The division Bryophyta, comprising the family Sphagnaceae contains one genus, Sphagnum, to which 292 (worldwide) known species of peat mosses are assigned to.

3.3.14

virgin material

raw material that has been mined, extracted or harvested and has never been previously used, developed, or processed

3.3.15

wood fibre

fiberized wood chips to which, if necessary, conditioning agents are added during the mechanical-thermal or steam-treatment fiberization process to stabilize the nitrogen imbalance or to dye the fibres

3.1.3 Terms relating to processing and manufacture

3.4.1

anaerobic digestion

controlled decomposition of biodegradable materials which is predominately anaerobic and at temperatures suitable for mesophilic or thermophilic bacteria

3.4.2

composting

controlled decomposition of biodegradable materials, which is predominantly aerobic and which allows the development of temperatures suitable for thermophilic bacteria as a result of biologically produced heat

3.4.3

drying

process to dry a material in order to reduce its moisture content, which can be achieved under natural conditions (e.g. drying of extracted peat or coir by wind and sun) or thermally (e.g. in a drying oven)

3.4.4

extraction

process of removing inorganic raw material (e.g. perlite, diabas) or organic raw material (e.g. peat) from its natural deposit for further processing

3.4.5

fiberization

mechanical-thermal extrusion or steam treatment of wood chips, the purpose of which is to generate high pressure and high temperatures up to 150 °C or higher, breaking the wood chips into wood fibres which are used as a growing media component

3.4.6

frost treatment

natural, in the field freezing through of extracted strongly decomposed peat to improve its physical properties (water capacity and air capacity) as a growing media component

3.4.7

hydraulic retention time

HRT

average residence time of the material in the digester vessel, determined by the loading rate and operational digester capacity

Note 1 to entry: The hydraulic retention time can be calculated by dividing the digester working volume (in m3) by the rate of flow of input materials into the digester (in m3 per day).

3.4.8

milling

process of grinding, cutting, pressing or crushing a material in a mill or by using a milling machine

3.4.9

pyrolysis

chemical decomposition of organic materials through the application of heat

Note 1 to entry: Biomass pyrolysis is the process used for the manufacture of biochar, whereby organic substances are broken down at temperatures ranging from 350 °C to 1 000 °C in a low-oxygen process.

3.4.10

precipitation

result of a chemical reaction in solution resulting in the formation of a solid product

3.4.11

sanitation

reduction of human, animal and plant pathogens to acceptable levels as a result of the treatment process

3.4.12

sieving

process of separating particulate or granular material into two or more size fractions using one or more sieves

3.1.4 Terms relating to sampling

3.5.1

batch

lot

quantity of goods manufactured by the same process under the same conditions, at the same time, and labelled in the same manner and are assumed to have the same characteristics to be sampled using a particular sampling plan

3.5.2

bulk material

material that is not packaged

3.5.3

consignment

quantity of goods dispatched or received at one time and covered by a particular contract or shipping document

Note 1 to entry: A consignment can be composed of a part of a batch (lot) or one or more batches (lots) of the same material or different materials.

3.5.4

combined sample

combination of all incremental samples taken from one sampled portion

3.5.5

final sample

in relation to chemical and physical testing only, a representative part of the combined sample taken from the sampled portion obtained, where necessary, by a process of reduction

3.5.6

incremental sample

quantity of material taken from one sampling point

3.5.7

laboratory sample

in relation to chemical and physical testing, a final sample intended for laboratory testing and in relation to microbiological testing, each separate segment sample intended for laboratory testing

3.5.8

sampled portion

in relation to sampling for chemical and physical testing, the quantity of material from the same batch from which one representative combined sample is taken and, in relation to sampling for microbiological testing, the quantity of material from the same batch from which segment samples are taken

3.5.9

sampling point

point from which the incremental sample is taken

3.5.10

test portion

quantity of material drawn from the test sample (or from the laboratory sample if both are the same) and on which the tests or observations are actually carried out

3.5.11

test sample

sample prepared from the laboratory sample and from which test portions will be taken

3.1.5 Terms relating to chemical properties

3.6.1

CAT

CaCl2/DTPA

solution for the extraction of soluble nutrients consisting of calcium chloride and diethylenetriaminepentaacetic acid (CaCl2/DTPA)

3.6.2

bioavailability

fractions of elements extractable by CaCl₂/DTPA that are interpreted as plant available

3.6.3

soluble element

element that can be extracted from a sample by using a specific extraction solution, such as water, CaCl2/DTPA or aqua regia

3.6.4

soluble nutrient

nutrient that can be extracted from a sample by using a specific extraction solution, such as water, CaCl2/DTPA or aqua regia

3.1.6 Terms relating to physical and physico-chemical properties

3.7.1

bulk density

indication of how much 1 l of the product weighs, being determined in a standardized way

Note 1 to entry: The bulk density is expressed in grams per litre (g/l) or in kilograms per cubic metre (kg/m3).

3.7.2

depth

linear dimension measuring how deep recess intrude into the media

3.7.3

electrical conductivity

ability of an aqueous extract of the sample to conduct electricity as a function of the ion concentration

3.7.4

height

linear dimension measured top to bottom

3.7.5

laboratory bulk density

density, expressed in grams per litre of the material as determined in the laboratory using a cylinder of known volume; the sample being compacted under defined conditions

3.7.6

length

longer linear dimension of the major surface of the test specimen

3.7.7

liquid form

suspension or solution

3.7.8

macroscopic impurity

material above 2 mm in any of the following form; glass, metal or plastic

3.7.8.1

glass

usually transparent, lustrous, hard and brittle material, generally composed of a silicate (such as silicon oxide, or quartz) combined with an alkali and sometimes other substances

3.7.8.2

metal

usually crystalline solid of rigid or malleable non-brittle material e.g. steel, iron, copper, lead and tin

Note 1 to entry: Ferrous stones are not considered to be metals and shall be considered as stones.

3.7.8.3

plastic

solid material which is usually man-made, oil-based, mouldable when soft, and light in weight

Note 1 to entry: Plastics include both fossil based and biobased plastics.

3.7.8.4

other material

unexpected material not accounted for as impurities

Note 1 to entry: For example stones.

3.7.8.5

stone

hard solid non-metallic mineral matter of which rock is made and of a small or moderate size

Note 1 to entry: Expanded clay granules and kitchenware shards shall be considered as stone.

3.7.9

mass

conventional mass as weighed in air of density 1,2 kg/m3

3.7.10

organic carbon

carbonaceous material emitted during combustion in which the carbon is chemically bonded to hydrogen and possibly also oxygen, nitrogen, sulphur, or other elements

3.7.11

organic matter

carbon fraction of a sample which is free from water and inorganic substances

3.7.12

oxygen uptake rate

indicator of the extent to which biodegradable organic matter is being broken down within a specified time period

3.7.13

particle size distribution

cumulative distribution of given particle size ranges (e.g. 0 mm to 2 mm, 2 mm to 4 mm, 4 mm to 8 mm, 8 mm to 16 mm) of a material and expressed as % by dry mass

3.7.14

quantity

out-turn volume or mass being determined in a standardized way

3.7.15

residual biogas potential

indicator of the gas released from a anaerobic digestion process

3.7.16

self-heating

exothermic reaction within a material resulting in a rise in temperature in the material

[SOURCE: ISO 4880:1997, 55]

3.7.17

solid form

form characterized by structural rigidity and resistance to changes of shape or volume and in which the atoms are tightly bound to each other, either in a regular geometric lattice (crystalline solids) or in an irregular manner (an amorphous solid)

3.7.18

solution

liquid that is free of solid particles or a gel and includes pastes

3.7.19

stability

degree of processing and biodegradation at which the rate of biological activity has slowed to an acceptably low and consistent level and will not significantly increase under favourable, altered conditions

3.7.20

suspension

two-phase dispersion in which solid particles are maintained in suspension in the liquid phase

3.7.21

total carbon

quantity of carbon present in the sample in the form of organic, inorganic and elemental carbon

3.7.22

total inorganic carbon

TIC

quantity of carbon that is liberated as carbon dioxide by acid treatment

3.7.23

total organic carbon

TOC

quantity of carbon that is converted into carbon dioxide by combustion and which is not liberated as carbon dioxide by acid treatment

3.7.24

width

shorter linear dimension of the major surface of the test specimen measured at right angles to the length

3.1.7 Terms relating to biological properties

3.8.1

specific pathogens

pathogenic or facultative pathogenic indicator microorganisms (e.g. E. coli, enterococci, Salmonella), the detection or quantification of which allows conclusions to be drawn about the hygienic status of soil improvers and growing media

3.8.2

colony forming unit

cfu

growth of individual bacterial cells into visible colonies on agar media, including on membrane filters overlaying the agar media

3.8.3

sterilization

process used to render product free from viable microorganisms

3.1.8 Terms relating to safety

3.9.1

contaminant

substance, material or agent that is unwanted in a soil improver or growing medium or their components

3.9.2

harm

physical injury or damage to the health of people or damage to property or the environment

[SOURCE: ISO/IEC Guide 51:2014, 3.1, modified – added “physical” before “injury”]

3.9.3

hazard

potential source of harm

[SOURCE: ISO/IEC Guide 51:2014, 3.2]

3.9.4

pollutant

contaminant which due to its properties, amount or concentration causes harm

3.9.5

potentially toxic element

chemical element that has a potential to cause toxicity to humans, flora and fauna

Note 1 to entry: Typically this term refers to “heavy metals” and other such as arsenic, selenium, boron, fluorine which exhibit a typical, dose related, sharp toxicity curve.

3.9.6

risk

combination of the probability of occurrence of harm and the severity of that harm

[SOURCE: ISO/IEC Guide 51:2014, 3.9, modified – deleted note 1 to entry]

3.9.7

reasonably foreseeable misuse

use of a product, process or service in a way not intended by the supplier, but which can result from readily predictable human behaviour

3.9.8

safety

freedom from unacceptable risk

(informative)

All terms defined in this document in alphabetical order

A		E		leonardite	3.3.9	R		test sample	3.5.11
additional labelling	3.1.1	electrical conductivity	3.7.3	lignite	3.3.10	reasonably foreseeable misuse	3.9.7	TIC	3.7.22
anaerobic digestion	3.4.1	extraction	3.4.4	liquid form	3.7.7	residual biogas potential	3.7.15	TOC	3.7.23
ash	3.3.1	F		lot	3.5.1	risk	3.9.6	total carbon	3.7.21
B		fiberization	3.4.5	M		S		total inorganic carbon	3.7.22
batch	3.5.1	final sample	3.5.5	macroscopic impurity	3.7.8	safety	3.9.8	total organic carbon	3.7.23
bioavailability	3.6.2	fresh crop digestate	3.3.7	mass	3.7.9	sampled portion	3.5.8	U
biochar	3.3.2	frost treatment	3.4.6	metal	3.7.8.2	sampling point	3.5.9	user	3.1.7
bulk density	3.7.1	G		milling	3.4.8	sanitation	3.4.11	V
bulk material	3.5.2	glass	3.7.8.1	O		self-heating	3.7.16	virgin material	3.3.14
C		growing medium	3.2.1	organic carbon	3.7.10	sieving	3.4.12	W
CaCl2/DTPA	3.6.1	growing medium component	3.2.2	organic material	3.3.11	soil improver	3.2.4	width	3.7.24
CAT	3.6.1	H		organic matter	3.7.11	soil improver component	3.2.5	wood fibre	3.3.15
cfu	3.8.2	harm	3.9.2	other material	3.7.8.4	solid form	3.7.17
coir	3.3.3	hazard	3.9.3	oxygen uptake rate	3.7.12	soluble elements	3.6.3
colony forming unit	3.8.2	height	3.7.4	P		soluble nutrients	3.6.4
combined sample	3.5.4	HRT	3.4.7	package	3.1.5	solution	3.7.18
compost	3.3.4	hydraulic retention time	3.4.7	particle size distribution	3.7.13	specific pathogens	3.8.1
composting	3.4.2	I		peat	3.3.12	Sphagnum	3.3.13
consignment	3.5.3	incremental sample	3.5.6	plastic	3.7.8.3	stability	3.7.19
container	3.1.2	industrial sludge	3.3.8	pollutant	3.9.4	sterilization	3.8.3
contaminant	3.9.1	intended use	3.1.3	potentially toxic element	3.9.5	stone	3.7.8.5
D		L		precipitation	3.4.10	strike	3.1.6
depth	3.7.2	labelling requirements	3.1.4	pre-shaped growing medium	3.2.3	suspension	3.7.20
digestate	3.3.5	laboratory bulk density	3.7.5	pyrolysis	3.4.9	T
digestate other than fresh crop digestate	3.3.6	laboratory sample	3.5.7	Q		TC	3.7.21
drying	3.4.3	length	3.7.6	quantity	3.7.14	test portion	3.5.10

Bibliography

[1] ISO 4880:1997, Burning behaviour of textiles and textile products — Vocabulary

[2] ISO 13833:2013, Stationary source emissions — Determination of the ratio of biomass (biogenic) and fossil-derived carbon dioxide — Radiocarbon sampling and determination

[3] ISO 19867‑1:2018, Clean cookstoves and clean cooking solutions — Harmonized laboratory test protocols — Part 1: Standard test sequence for emissions and performance, safety and durability

[4] ISO/IEC Guide 51, Safety aspects — Guidelines for their inclusion in standards

[5] Regulation (EU) 2019/1009 of the European Parliament and of the Council of 5 June 2019 laying down rules on the making available on the market of EU fertilising products and amending Regulations (EC) No 1069/2009 and (EC) No 1107/2009 and repealing Regulation (EC) No 2003/2003

[6] European Commission (2021). Communication from the commission. Concerning the visual appearance of the label on EU fertilising products referred to in Annex III to Regulation (EU) 2019/1009 of the European Parliament and of the Council

[7] Michaelis D. (2019): The Sphagnum species of the world. Bibliotheca Botanica 162, 435 pp

[8] Schmilewski G. “Kultursubstrate und Blumenerden – Eigenschaften, Ausgangsstoffe, Verwendung”. Online publication by Industrieverband Garten e. V. IVG, Germany, 2018

[9] https://www.european-biochar.org/media/doc/2/version_en_9_2e.pdf

[10] Neuendorf K.K.E. American Geological Institute (2005). Springer Science & Business Media, 2005, pp. 369., Glossary of Geology, ISBN978-0-922152-76-6

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