ISO 21255:2018

Fine bubble technology - Storage and transportation of ultrafine bubble dispersion in water

This document describes the procedures and equipment for storage and transportation of ultrafine bubble dispersions in water and specifies the related requirements in order to maintain such bubble characteristics as size and number concentration.

Technologie des fines bulles — Conservation et transport d'ultrafines bulles en dispersion dans l'eau

General Information

• Status: Published
• Publication Date: 11-Oct-2018
• ICS: 07.030 - Physics. Chemistry
• Technical Committee: ISO/TC 281 - Fine bubble technology
• Drafting Committee: ISO/TC 281/WG 2 - Fine bubble characterization and measurement
• Current Stage: 9093 - International Standard confirmed
• Start Date: 28-Oct-2024
• Completion Date: 13-Dec-2025

Relations

• Consolidated By: ISO 16486-3:2020 - Plastics piping systems for the supply of gaseous fuels - Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing - Part 3: Fittings
• Effective Date: 06-Jun-2022

Overview

ISO 21255:2018 establishes international standards for the storage and transportation of ultrafine bubble dispersions (UFBD) in water, providing essential guidelines to maintain the quality and stability of these dispersions. Ultrafine bubbles-also known as nanobubbles-have unique properties that make them valuable across various industries, including agriculture, semiconductor manufacturing, water treatment, and surface cleaning.

This standard specifies the necessary procedures, equipment, and environmental conditions required to preserve critical characteristics of the ultrafine bubbles, such as size and number concentration. By ensuring integrity during storage and transport, ISO 21255:2018 supports the expansion of fine bubble technology applications beyond on-site generation and use.

Key Topics

• Ultrafine Bubble Dispersion (UFBD): Defined as liquid containing ultrafine bubbles in water, requiring specific handling to preserve bubble stability.
• Storage Substances: Requirements emphasize using grade 1, 2, or 3 water (per ISO 3696) free from chemically active or bacterial contaminants that could alter UFBD properties.
• Containers and Filling Procedures:
  • Use rigid containers to minimize contact with air and mechanical disturbances.
  • Recommended container material is borosilicate glass 3.3 (ISO 3585) for its stability and inertness.
  • Interfaces should use low gas-permeable flexible materials like poly(isobutylene-isoprene) (IIR) to accommodate pressure changes without bubble deterioration.
  • Ensure sterilization (heat or UV) to avoid biological contamination.
• Storage Conditions:
  • Maintain temperature between 5 °C and 35 °C; avoid freezing (<0 °C) that causes bubble extinction.
  • Protect from direct sunlight and vibrations.
  • Consistent environmental conditions prevent degradation of bubbles.
• Transportation Requirements:
  • Similar temperature range applies (5 °C to 35 °C), with atmospheric pressure between 750 hPa and 1050 hPa.
  • Minimize vibrations and shocks; allowable acceleration below 100 m/s², with limited exceptions.
  • Use courier or specialized “fragile” transportation services to reduce risks.
• Record Keeping: Documenting storage and transportation parameters (dates, container details, environmental conditions) is mandatory to ensure traceability and quality control.

Practical Applications

ISO 21255:2018 provides a framework that supports industries requiring reliable supply chains for ultrafine bubble dispersions. Key applications include:

• Agricultural Enhancement: Transporting ultrafine bubbles for irrigation and plant growth stimulation without compromising bubble stability.
• Semiconductor Manufacturing: Safe handling of ultrafine bubble dispersions used in delicate processes like wafer separation.
• Water Treatment and Purification: Enabling off-site generation and distribution of ultrafine bubble water for advanced cleaning and pollution control.
• Surface Cleaning Solutions: Supplying stable ultrafine bubble formulations for removing oil, stains, and contaminants on infrastructure.

By standardizing storage and transport protocols, organizations can expand the deployment of ultrafine bubble technology beyond generation sites, enabling broad-scale commercial use and industrial integration.

Related Standards

ISO 21255:2018 references several complementary standards critical to its context:

• ISO 20480-1: Defines terminology and general principles for fine bubble technology and measurement techniques.
• ISO 3696: Specifies water quality classification for analytical laboratory use, relevant for water diluents in UFBD.
• ISO 3585: Covers properties of borosilicate glass 3.3 used in containers.
• ISO 4796-1: Describes laboratory glass screw-neck bottles suitable for UFBD handling.
• ISO/IEC Guide 98-1: Addresses uncertainty in measurement, ensuring precise quality assessment.

Compliance with these interconnected standards enhances the overall quality and reliability of ultrafine bubble technology applications.

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Keywords: ISO 21255, ultrafine bubble dispersion, nanobubbles, fine bubble technology, UFBD storage, UFBD transportation, bubble stability, borosilicate glass container, water diluent, fine bubble standards, industrial ultrafine bubbles, bubble number concentration, bubble size integrity.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 21255
First edition
2018-11
Fine bubble technology — Storage
and transportation of ultrafine bubble
dispersion in water
Technologie des fines bulles — Conservation et transport d'ultrafines
bulles en dispersion dans l'eau
Reference number
©
ISO 2018
© ISO 2018
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ii © ISO 2018 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Substance for storage and transportation . 1
5 Container and filling . 2
6 Storage . 3
7 Transportation . 3
8 Records . 3
Bibliography . 5
Foreword
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bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
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described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents 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).
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.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 281, Fine bubble technology.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv © ISO 2018 – All rights reserved

Introduction
Fine bubble technology applications have grown steadily in recent years. They now embrace a diverse
range of industrial activities from enhancing the growth rates of plants in agriculture to the separation
peel-off of solar panel silicon wafers in semiconductor manufacturing process.
Improved advanced cleaning purification of waste water and enhanced high throughput removal of
lubricant oil on machined works and of salt stains from a surface of traffic infrastructures, have also
been demonstrated.
Most of these applications are currently limited to the site where the generating system of fine bubble
water is installed close to the application objects and operated simultaneously to the application.
Expansion for applications where the site of bubble application is different from that of generation is
being implemented by some innovative industries, but there are currently no concrete guidelines for
storage and transportation of fine bubble water, as typical ultrafine bubbles (UFB) are known to have
high stability once generated. The purpose of this document is to expand the scope of application of
initial measurements of fine bubble quality downstream in the supply chain.
This document specifies the requirements related to the planning, equipment and operation process
necessary to store and transport ultrafine bubble dispersions without significant deterioration in terms
of number concentration index. This document is intended to help assessing the acceptable conditions
and periods for storage and transportation that guarantee integrity of ultrafine bubble quality.
INTERNATIONAL STANDARD ISO 21255:2018(E)
Fine bubble technology — Storage and transportation of
ultrafine bubble dispersion in water
1 Scope
This document describes the procedures and equipment for storage and transportation of ultrafine
bubble dispersions in water and specifies the related requirements in order to maintain such bubble
characteristics as size and number concentration.
2 Normative
...