ACA mass covers only vehicles inside the accreditation's scope, so the operator keeps effective control over every nominated vehicle and every trailer run with it, including vehicles supplied by subcontractors where that applies. It can tell at any moment which vehicles are operating under the accreditation and can show that they are technically able to run within the applicable mass limits, holding accurate, current information on identity, configuration, specifications and any mass concessions or authorisations; subcontracted vehicles are tied firmly enough to the accreditation that mass controls apply to them consistently, so that mass risk is managed across the whole operating fleet and not just the vehicles the operator owns. Six things are looked for: every vehicle and trailer operating under the accreditation can be identified at any given time; current, sufficiently detailed records exist for all of them, subcontractor vehicles included, to support audit, review and regulatory assurance; those records show identity, configuration and whether mass concessions or authorisations apply; the vehicles are demonstrably able, by design and specification, to operate within the applicable axle and gross mass limits; where network access needs a mass authorisation, it is current and covers the vehicles concerned; and subcontractor or third-party vehicles are under controls that keep them within the operator's ACA mass rather than operating outside it.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.