ISO 23016-2:2026

• Abstract:

  This document specifies a method to test the promotion of the germination of barley seeds, using ultrafine bubble (UFB) water produced from an ultrafine bubble water generating system. The performance of the method is assessed by measuring the ratio of barley seed germination.

• Status: Published
• Publication Date: 30-Jun-2026
• ICS: 07.030 - Physics. Chemistry
• ICS: 65.020.20 - Plant growing
• Technical Committee: ISO/TC 281 - Fine bubble technology
• Drafting Committee: ISO/TC 281/WG 3 - Applications of fine bubble technology
• Current Stage: 6060 - International Standard published
• Start Date: 01-Jul-2026
• Due Date: 17-Aug-2026
• Completion Date: 01-Jul-2026

• Revises: ISO 23016-2:2019 - Fine bubble technology — Agricultural applications — Part 2: Test method for evaluating the promotion of the germination of barley seeds
• Effective Date: 22-Feb-2025

Overview

ISO 23016-2:2026 - Fine bubble technology - Agricultural applications - Part 2: Test method for evaluating the promotion of the germination of barley seeds is an international standard developed by ISO for the assessment of fine bubble technology's effects on barley seed germination. This document outlines a systematic test method for evaluating the promotion of barley seed germination when exposed to ultrafine bubble (UFB) water, produced using an ultrafine bubble water generating system. The key performance indicator is the germination ratio of barley seeds, providing standardized benchmarks for technology providers, agricultural researchers, and equipment manufacturers.

Key Topics

• Fine Bubble Technology in Agriculture: Focuses on ultrafine bubbles (less than 1 µm in diameter) and their application in agricultural seed treatment.
• UFB Water Generation: Details the use of specialized systems that produce UFB water to boost agricultural output, specifically seed germination.
• Barley Seed Germination Test: Describes controlled experimental procedures for soaking barley seeds in both UFB water and control water to assess improvement in germination rates.
• Measurement and Data Analysis: Outlines standardized methods for observing, recording, and calculating germination ratios, as well as assessing UFB-enabled efficiency.
• Required Apparatus and Conditions: Lists equipment such as beakers, constant-temperature water tanks, pH meters, and specific seed selection criteria for valid results.

Applications

• Seed Treatment Optimization: Agricultural scientists and seed companies can use this standardized method to compare the effectiveness of UFB water in promoting barley seed germination, leading to better seed treatment protocols.
• Technology Validation: Equipment manufacturers and developers of ultrafine bubble generators can demonstrate the efficacy and reproducibility of their technologies using this international baseline.
• Agricultural Productivity: Farms aiming for improved crop establishment can adopt UFB water systems, validated by this method, to achieve higher and more uniform germination rates.
• Research and Development: Universities and research institutions can apply this method to conduct repeatable, comparable studies on the impact of fine bubble technologies in various agricultural contexts.
• Quality Control: Standardized testing ensures batch-to-batch consistency when producing or supplying UFB water or equipment to the agricultural sector.

Related Standards

• ISO 20480-1: Fine bubble technology - General principles for usage and measurement of fine bubbles - Part 1: Terminology
  • Establishes terminology and foundational concepts for fine and ultrafine bubble technology.
• ISO 20480-2: Fine bubble technology - General principles for usage and measurement of fine bubbles - Part 2: Categorization of the attributes of fine bubbles
  • Details classification of fine bubbles, providing a basis for the methods used in ISO 23016-2.
• JIS K 0557: Water used for industrial water and wastewater analysis, referenced for raw water quality requirements.
• ISO 18763: Soil quality - Determination of the toxic effects of pollutants on germination and early growth of higher plants
  • Offers additional methodologies for plant germination testing.

Keywords: ISO 23016-2:2026, fine bubble technology, ultrafine bubble water, barley seed germination, agricultural applications, UFB water, test method, seed treatment, agricultural standard, germination ratio, equipment validation, crop productivity, standardization in agriculture.

By adopting ISO 23016-2:2026, stakeholders in the agricultural and fine bubble technology sectors can achieve greater accuracy and comparability in assessing the benefits of ultrafine bubble water, thereby supporting innovation and quality assurance in seed germination practices.

International
Standard
ISO 23016-2
Second edition
Fine bubble technology —
2026-07
Agricultural applications —
Part 2:
Test method for evaluating the
promotion of the germination of
barley seeds
Technologie des fines bulles — Applications agricoles —
Partie 2: Méthode d'essai pour l'évaluation de la promotion de la
germination des graines d'orge
Reference number
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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or ISO’s member body in the country of the requester.
ISO copyright office
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Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General testing principle . 2
4.1 General overview of the test system .2
4.2 Assessment of test results .3
5 Test subjects . 4
6 Apparatus and test equipment . 4
6.1 Seeds for germination test .4
6.2 UFB generating system and UFB water .4
6.3 Measurement and observation equipment.5
6.4 Beakers .5
6.5 Constant-temperature water tank .5
6.6 Plastic bags .5
6.7 Test tray and filter paper .5
6.8 Limit sample for inspection .5
6.9 Maintenance of measurement devices and equipment .6
6.9.1 Maintenance .6
6.9.2 Calibration . . .6
7 Test environment . 6
7.1 Temperature conditions .6
7.2 Environmental parameters to be measured .6
8 Test procedure . 6
8.1 Test period and interval between inspections .6
8.2 Seed selection and packing into bags .6
8.3 Use of UFB water and control water .7
8.4 Tray preparation and seed sowing .8
8.5 Inspection and recording .9
9 Test report . 9
Annex A (informative) Example of test result at testing laboratory .10
Annex B (normative) Barley seed limit samples .12
Bibliography .13

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
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with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 281, Fine bubble technology.
This second edition cancels and replaces the first edition (ISO 23016-2:2019), of which it constitutes a minor
revision. The changes are as follows:
— Table 1 has been inserted in Clause 5 indicating the water quality of A2, according to JIS K 0557, with six
items originally provided in the footnote.
A list of all parts in the ISO 23016 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
Introduction
Considering the increasing use of fine bubble technology in agriculture, this document has been developed
to establish standards in this area, with particular focus on promoting the germination and growth of barley
seeds.
The use of fine bubble technology in agriculture has been confirmed to benefit various types of agricultural
products and has attracted the interest of various countries. Application of the technology to leafy vegetables
in agriculture is already well-established, and this is being expanded to seed germination and growth as
well. Worldwide as well, standardization of fine bubble technology in the field of agriculture is not only being
spotlighted but is being conducted in practice at a rapid pace. The technology is expected to blossom rapidly.
Fine bubble technology has been applied successfully not only in agriculture but also in the fields of
environmental science, food, marine products, medicine, etc. Wide-ranging progress in standardizing the
technology is being made in these fields. The achievement of standardization in various fields is expected to
result in increased worldwide recognition of fine bubble technology in the future.

v
International Standard ISO 23016-2:2026(en)
Fine bubble technology — Agricultural applications —
Part 2:
Test method for evaluating the promotion of the germination
of barley seeds
1 Scope
This document specifies a method to test the promotion of the germination of barley seeds, using ultrafine
bubble (UFB) water produced from an ultrafine bubble water generating system. The performance of the
method is assessed by measuring the ratio of barley seed germination.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 20480-1, Fine bubble technology — General principles for usage and measurement of fine bubbles — Part 1:
Terminology
ISO 20480-2, Fine bubble technology — General principles for usage and measurement of fine bubbles — Part 2:
Categorization of the attributes of fine bubbles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 20480-1 and ISO 20480-2 and the
following 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
germination
appearance of a radicle of at least 1 mm of length
[1]
[SOURCE: ISO 18763:2016, 3.7, modified — "root" has been replaced by " radicle".]
3.2
ultrafine bubble generating system
UFB generating system
equipment that uses water and air to generate ultrafine bubbles by mechanical action
Note 1 to entry: Ultrafine bubbles (UFB) are bubbles with a diameter of less than 1 µm. See ISO 20480-1.

3.3
ultrafine bubble water
UFB water
water that includes UFB
Note 1 to entry: UFB are defined in ISO 20480-1.
3.4
control water
water for use as a control sample for the effects of UFB
3.5
raw water
distilled water supplied as a raw material for both UFB water (3.3) and control water (3.4)
3.6
test water
either UFB water (3.3) or control water (3.4)
3.7
UFB section
test beaker containing UFB water (3.3) for use in germination tests of barley seeds in UFB water
3.8
control section
test beaker containing control water (3.4) for use in germination tests of barley seeds in control water
3.9
germination ratio
G
ratio of the seeds observed during inspection to have germinated to the total number of seeds provided for
the test
3.10
UFB enabled efficiency
P
quantity measuring the efficiency of UFB for its enhancement in the germinating period
Note 1 to entry: P is defined by Formula (1).
4 General testing principle
4.1 General overview of the test system
UFB water shall be generated through the supply of raw water to the ultrafine bubble generating system.
The UFB water shall be supplied to the UFB section to promote the germination of the barley seeds that
have been supplied to the UFB section. In addition, raw water for control purposes that does not contain
UFB shall be supplied directly to the control section. Figure 1 shows the constitutive principle of the growth
promotion performance test.
Figure 1 — General view of growth promotion performance test system
4.2 Assessment of test results
The germination ratio, G, is obtained by calculating the number of germinated seeds to the number of all
seeds tested for each inspection.
The development of the germination ratio is assumed to be expressed by a specified S-curve regression
[2],[3]
function and a parameter T related to the delay in the germination is to be inferred by the process as
[4]-[10]
described below for each section. The relative difference of the parameter for UFB section to control
section is the measure for the performance of the fine bubble enhanced performance, defined as UFB enabled
efficiency, P, to be reported.
Efficiency, P, is given by Formula (1):
PT controlUTTFB / control (1)
  
50 50 50
where
P is the efficiency;
T (control) is
...