This document specifies laboratory methods for determination of the soil water-retention characteristic.
This document applies only to measurements of the drying or desorption curve.
Four methods are described to cover the complete range of soil water pressures as follows:
a) method using sand, kaolin or ceramic suction tables for determination of matric pressures from 
0 kPa to −50 kPa;
b) method using a porous plate and burette apparatus for determination of matric pressures from 
0 kPa to −20 kPa;
c) method using a pressurized gas and a pressure plate extractor for determination of matric 
pressures from −5 kPa to −1 500 kPa;
d) method using a pressurized gas and pressure membrane cells for determination of matric pressures 
from −33 kPa to −1 500 kPa.
Guidelines are given to select the most suitable method in a particular case.nd edition 2019-09 Soil quality — Determination of the water-retention characteristic — Laboratory methods Qualité du sol — Détermination de la caractéristique de la rétention en eau — Méthodes de laboratoire Reference number ISO 11274:2019(E) ？ ISO 2019 ISO 11274:2019(E) COPYRIGHT PROTECTED DOCUMENT ？ ISO 2019 All rights reserved. Unless otherwise s