Foreword

This BSI Flex was sponsored by the Institution of Civil Engineers (ICE). Its development was facilitated by BSI Standards Limited and it was released under licence from The British Standards Institution. It came into effect on 31 October 2023.

Acknowledgement is given to the following organizations that funded this BSI Flex:

• AMCRETE UK
• DB Group
• Environment Agency
• I3P
• Laing O’Rourke
• Mineral Products Association (MPA) Cement
• Network Rail
• Wagners (EFC Green Concrete Technology UK Ltd)

Acknowledgement is given to James Aldred, Concrete Future, as the technical author, and the following organizations that were involved in the development of this BSI Flex as members of the Advisory Group:

• AKT II
• AMCRETE UK
• B/517
• CEMEX
• Concrete Future
• ConcreteZero
• DB Group
• Environment Agency
• GPT
• Laing O’Rourke
• Material Evolution
• Mineral Products Association (MPA) Cement
• OTB Concrete
• Ramboll Buildings
• University of Sheffield

The British Standards Institution retains ownership and copyright of this BSI Flex. BSI Standards Limited, as the publisher of the BSI Flex, reserves the right to withdraw or amend this BSI Flex on receipt of authoritative advice that it is appropriate to do so.

This BSI Flex is not to be regarded as a PAS or British Standard.

The BSI Flex process enables a standard to be rapidly developed, on an iterative basis, in order to fulfil an immediate stakeholder need. A BSI Flex can be considered for further development as a PAS or British Standard, or constitute part of the UK input into the development of a European or international standard.

The content in this version is part of an iterative process. It is likely to change from time to time with subsequent iterations.

Information about this document

This is Version 1 of BSI Flex 350, which has been released to enable stakeholders to engage with the initial content and feed back comments for further versions of the document to be developed. This is the first public consultation of this BSI Flex and so the content is not to be considered as having received wider feedback. Users are therefore encouraged to comment on this version.

This publication can be withdrawn, revised, partially superseded or superseded. Information regarding the status of this publication can be found in the Standards Catalogue on the BSI website at bsigroup.com/standards, or by contacting the Customer Services team.

Where websites and webpages have been cited, they are provided for ease of reference and are correct at the time of publication. The location of a webpage or website, or its contents, cannot be guaranteed.

Relationship with other publications

Upon release of Version 2 of BSI Flex 350, PAS 8820 is to be withdrawn.

Use of this document

As a code of practice, this BSI Flex takes the form of recommendations and guidance. It is not to be quoted as if it were a specification. Users are expected to ensure that claims of compliance are not misleading.

Users may substitute any of the recommendations in this BSI Flex with practices of equivalent or better outcome. Any user claiming compliance with this BSI Flex is expected to be able to justify any course of action that deviates from its recommendations.

Presentational conventions

The provisions of this document are presented in roman (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb is “should”.

Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.

Where words have alternative spellings, the preferred spelling of the Shorter Oxford English Dictionary is used (e.g. “organization” rather than “organisation”).

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

Compliance with a BSI Flex cannot confer immunity from legal obligations.

WARNING. Where skin is in contact with fresh alternative binder system (ABS) concrete, skin irritations are likely to occur owing to the alkaline nature of cement. The abrasive effects of sand and aggregate in ABS concrete can aggravate the condition. Potential effects range from dry skin, irritant contact dermatitis, to – in cases of prolonged exposure – severe burns. Take precautions to avoid dry ABS entering the eyes, mouth and nose when mixing mortar or concrete by wearing suitable protective clothing. Care is necessary to prevent fresh ABS concrete from entering boots and use working methods that do not require personnel to kneel in fresh ABS concrete. Unlike heat burns, ABS and alkali burns might not be felt until sometime after contact with fresh ABS concrete, so there might be no warning of damage occurring. If ABS or ABS concrete enters the eye, immediately wash it out thoroughly with clean water and seek medical treatment without delay. Wash wet ABS concrete off the skin immediately. Barrier creams can be used to supplement protective clothing but are not an alternative means of protection.

BSI Flex 350 v1.0:2023-10

Alternative binder systems for lower carbon concrete. Code of Practice

Published:

31 Oct 2023

Withdrawn:

3 Sep 2024