Continuous Survey Machinery
Abbreviation: CMS
Class arrangement allowing machinery items to be surveyed in rotation by the chief engineer rather than in one yard period.
In practice
Chief engineer schedules surveys to balance machinery downtime; class verifies records at intermediate survey. CMS reduces drydock-period machinery work substantially.
Regulatory detail & full definition
Continuous Survey of Machinery — IACS UR Z7 class arrangement allowing machinery items to be surveyed in rotation by the chief engineer rather than during a single concentrated yard period. Items are listed in a CSM list with intervals not exceeding 5 years per item; the chief engineer carries out the surveys and submits records, with class verification at intervals. CSM reduces the time machinery is offline during the renewal survey because most items are already credited. Most large operators run their fleets under CSM; class society audits the records during periodic surveys.
Authoritative source: IACS Unified Requirements ↗
Related
Source: IACS UR Z7
High confidence
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