This is the first edition of CSA Standard Q635, Guide to Life Cycle Costing. This document has been developed by the CSA Technical Committee on Dependability (formerly known as Reliability, Availability and Mai‘ntainability, (RAM)) under the jurisdiction of the CSA Steering Committee on Business Management'Systems. It has been approved by both these committees. A corresponding document is currently being developed by IEC (International Electrotechnical Commission) TC 56.
(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
(3) This publication was developed by consensus, which Is defined by the CSA Regulations Governing
Standardization as ”substantial agreement reached by concerned interests. Consensus includes an attempt
to remove all objections and implies much more than the concept of 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 the publication.
(4) CSA Standards are subject to periodic review, and suggestions for their improvement will be referred to
the appropriate committee.
(5) All enquiries regarding this Standard, including requests for interpretation, should be addressed to
Canadian Standards Association, Standards Development, 178 Rexdale Boulevard, Rexdale, Ontario
Requests for interpretation should
(a) define the problem, making reference to the specific clause, and, where appropriate, include an
(b) provide an explanation of circumstances surrounding the actual field condition; and
(c) be phrased where possible to permit a specific ”yes or ”no answer
Interpretations are published in CSA’s periodical Info Update. For subscription details, write to CSA Sales
Promotion, Info Update, at the address given above.
1.1 This Standard provides a general introduction to the concept of life cycle costing. Although life cycle costs consist of many contributing elements, this Standard particularly highlights the costs associated with dependability elements (reliability, availability, maintainability, and maintenance support) of the product. It explains the purpose and usefulness of life cycle costing and outlines the general approaches involved.
The Standard identifies typical life cycle cost elements to facilitate project and programme planning. It also provides general guidance for conducting and documenting a life cycle cost analysis, including life cycle cost model development.
The Standard is intended for use by both suppliers and users of products.
1.2 Adherence to this Standard will
(a) facilitate a consistent and structured approach to life cycle costing analysis;
(b) provide common definitions for the life cycle costing process, thus improving understanding and communication of it; and
(c) ensure a uniform approach to documentation of life cycle costing analysis, thus assisting the decision makers and facilitating comparison between different analyses.
1.3 This Standard does not
(a) provide specific criteria for identifying the need for life cycle costing analysis; or
(b) specify detailed life cycle costing methodologies for specific applications.
Note: Life cycle costing analysis is applicable for comparative evaluations even when few data are available. Life cycle costing analysis is also useful in estimating the costs of a product at any time during its life cycle.