Glossary: O

6 terms.

• Oil Discharge Monitoring and Control System
  Equipment on oil tankers that continuously monitors the oil content and flow rate of overboard discharges to ensure MARPOL compliance.
• Oil Mist Detector
  A crankcase monitoring device that samples air from each crankcase compartment and alarms if oil mist concentration reaches explosive levels.
• Oil Record Book
  A mandatory log in which all oil-related operations including bilge pumping and bunkering must be recorded under MARPOL Annex I.
• Oiler
  An engine department rating who lubricates machinery, maintains oil records, and stands engine room watches.
• Oily Water Separator
  Equipment that separates oil from bilge water to reduce oil content to 15 ppm before overboard discharge under MARPOL.
• Ordinary Seaman
  Entry-level unlicensed deck rating assigned general duties under the supervision of ABs and the bosun.