CSA Group CSA/ANSI R118:24 National Standard of Canada American National Standard CarbonStarⓇ: Concrete carbon intensity quantification and verification

Preface

This is the first edition of CSA/ANSI R118, CarbonStarⓇ: Concrete carbon intensity quantification and verification. It replaces CSA SPE-112, CarbonStarⓇ : Technical specification for concrete carbon intensity quantification and verification, published in 2021.

This Standard was prepared by the Technical Committee on Concrete Carbon Intensity Quantification and Verification, under the jurisdiction of the Strategic Steering Committee on Environment and Business Excellence, and has been formally approved by the Technical Committee.

This Standard has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group.

This Standard has been approved by the American National Standards Institute (ANSI) as an American National Standard.

Notes:

1) Use of the singular does not exclude the plural (and vice versa) when the sense allows.

2) Although the intended primary application of this Standard is stated in its Scope, it is important to note that it remains the responsibility of the users of the Standard to judge its suitability for their particular purpose.

3) This Standard was developed by consensus, which is defined by CSA Policy governing standardization — Code of good practice for standardization as “substantial agreement. Consensus implies much more than a simple majority, but not necessarily unanimity”. It is consistent with this definition that a member may be included in the Technical Committee list and yet not be in full agreement with all clauses of this Standard.

4) To submit a request for interpretation of this Standard, please send the following information to [email protected] and include “Request for interpretation” in the subject line:

a) define the problem, making reference to the specific clause, and, where appropriate, include an illustrative sketch;

b) provide an explanation of circumstances surrounding the actual field condition; and

c) where possible, phrase the request in such a way that a specific “yes” or “no” answer will address the issue.

Committee interpretations are processed in accordance with the CSA Directives and guidelines governing standardization and are available on the Current Standards Activities page at standardsactivities.csagroup.org.

5) This Standard is subject to review within five years from the date of publication. Suggestions for its improvement will be referred to the appropriate committee. To submit a proposal for change, please send the following information to [email protected] and include “Proposal for change” in the subject line:

a) Standard designation (number);

b) relevant clause, table, and/or figure number;

c) wording of the proposed change; and

d) rationale for the change

1 Scope

1.1 General

This Standard provides minimum requirements and recommendations for the quantification and verification of the carbon intensity in a unit of concrete, including any carbon that is permanently sequestered during the production of the concrete and/or its input materials. Therefore, this number could be either positive or negative.

The quantification calculation results in a CarbonStarⓇ rating expressing:

a) the carbon intensity of concrete in kilograms (pounds) of CO2 and/or CO2e per cubic metre (cubic yard), subject to the methodology in this Standard; and

b) where applicable, the net CO2 sequestered in kilograms (pounds) per cubic metre (cubic yard), or as otherwise required for the purposes of carbon credits, offsets, or tax incentives.

Note: This Standard provides a methodology for quantifying carbon emissions and sequestration for a declared unit of 1 m3 (1.308 yd3) of concrete. When selecting concrete options for a given application, functional criteria, including strength, constructability, performance, and durability, also need to be considered.

For example, in Canada, CSA A23.1 provides performance and durability requirements for ready-mixed concrete, CSA A23.4 covers these same requirements for precast concrete, and CSA A23.3 covers structural requirements; for specific types of structures, CSA S6 covers bridge construction, and CSA S413 covers parking structures. In the USA, ACI 318 covers structural and durability requirements for buildings, ACI 350.5 covers environmental structures, and ACI 562 covers concrete repairs.

Annex D provides a sample template that can be used for documenting the use and outputs of this Standard.

1.2 Terminology

In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard.

Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material.

Notes to tables and figures are considered part of the table or figure and may be written as requirements.

Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.