Terms and definitions | MCHW Information Hub

Please find below a reference list of terms used in the MCHW information hub.

Term	Abbreviation	NOTES / DEFINITION
Additional requirement	AR	Supplementary requirement for which there is no equivalent within an SHW or IfS document
Cancelled requirement	CR	Requirement within an SHW or IfS document that has been cancelled or deleted.
Contract documents		Set of documents containing the works information, conditions of contract and pricing documents.
Contract Specific Appendix		Appendix given in the old MCHW at the end of each Notes for Guidance document, providing advice for the compilation of the contract-specific specifications (now replaced by the Works Specific Requirements templates).
Country-specific version		Version of a relevant SHW, IfS and WSR template specific to a relevant Overseeing Organisation, downloadable from the Standards for Highways website.
Design Manual for Roads and Bridges	DMRB	Document set containing the Overseeing Organisations’ Organisations’ requirements and advice for planning, design, inspection, assessment, maintenance, operation and disposal of the Overseeing Organisations’ motorway and all-purpose trunk roads.
Departure from standard		Formal approval mechanism for works on the Strategic Road Network that do not comply with the standards. Uses include undertaking value engineering, making innovations, or if requirements cannot be met otherwise.
Element		Contract-specific items identified to break and organise the content into specific components and facilitate the organisation of tasks and sub-tasks (defined at designer’s team discretion as done in the past).
Highway Construction Details	HCD	Set of standard drawings provided in the old MCHW under Volume 3.
Instructions for Specifiers	IfS	Document set contained in the MCHW providing instructions to the Specifier on the inclusion of contract specific requirements using Works Specific Requirements (WSR) templates. The IfS documents also replicate the SHW constructor requirements within their texts to aid the compilation of the contract-specific requirements.
Manual of Contract Documents for Highway Works	MCHW	Document set that contains information to facilitate the production of works specifications for the construction of the works. Updated MCHW: indicates the version published in September 2025. Old / former MCHW: indicates previous versions.
Method of Measurement for Highways Works	MMHW	Document set contained in the MCHW providing the methods of measurement to be used for the preparation of bills of quantities
National alteration		Term used to indicate specific rules of the Overseeing Organisations contained in the old MCHW (now replaced by the national variations presented as Nationally Determined Requirements and Nationally Determined Sections).
Nationally Determined Requirement	NDR	Individual requirements presented within the main text of a relevant SHW / IfS document (relevant when there is small variation between OOs’ requirements).
Nationally Determined Section	NDS	Ad hoc sections introduced in the main text of a relevant SHW / IfS document (relevant when there is significant variation between OOs’ requirements).
Notes for Guidance	NfG	Set of documents provided in the old MCHW under Volume 2, which was used for the preparation of the contract specific specifications, including the Contract Specific Appendices (now replaced by the Instructions for Specifiers documents).
Operational Technology Standards Library	OTSL	Standards covering operational technology requirements and advice relating to works on the UK motorway and all-purpose trunk roads (formerly TSS Plans Registry).
Overseeing Organisations	OO	National Highways and the highways or roads authorities of Scotland, Wales and Northern Ireland and their successors.
Requirement and Advice Document	RAD	Collective term for the DMRB and associated National Application Annexes, MCHW and associated SHW, IfS, MMHW and WSRs.
Road Investment Strategy	RIS	Five year DfT strategy for investment in and management of the UK strategic road network. RIS2 refers to the period April 2020- March 2025.
Specification for Highway Works	SHW	Document set contained in the MCHW providing constructor requirements for the implementation of highway works, to be used as the base specification in highway contracts. This only shows constructor requirements.
Specifier		The party compiling the contract specification (this term replaces the term “Compiler” used in the old MCHW).
Specifier instruction	SI	Instruction providing the required works specific requirements related to the constructor requirements.
Standards for Highways website	SfH	Website managed by National Highways on behalf of the four Overseeing Organisations.
Substitute requirement	SR	Requirement that replaces an existing requirement within an SHW or IfS document.
Technical Standards Group	TSG	National Highways team responsible for the process of developing and publishing RADs.
Works information		Also called “contract scope” in NEC terms. This is given by the works specification content, the contract drawings and other content like quality documents, environmental content, etc.
Works Specific Requirements	WSR	Works specific content to be used in conjunction with SHW constructor requirements for the particular scheme/project. New WSR templates are provided.
Works specification		Also called “contract specification”. Set of requirements dealing with the works, which can include requirements on geometry, constructor design, performance, activities, verification, documentation submission and limitations of construction activities.