🔍 Key Concepts

• Operating draft vs. survival draft on a mobile offshore drilling unit (MODU) like DEEP DRILLER • How critical motion limits (roll, pitch, heave, etc.) relate to safety and evacuation conditions • The difference between environmental limits (wind, waves) and unit response (motions)

💭 Think About

• Which of the choices describes a condition of the rig itself (its motions and stability) rather than just outside weather conditions? • When deciding to stay at operating draft, is it more important to look at actual motions and stability limits or just raw wind/wave numbers? • Which option reflects a measured or calculated limit that the rig’s operating manual would specifically track during operations?

✅ Before You Answer

• Identify which answer choice refers to measured vessel performance instead of just environmental values. • Ask: when deciding whether to deballast to survival draft, what does the MODU operating manual usually tell you to monitor continuously? • Verify which option would be used as a formal go/no-go criterion for staying at operating draft in heavy weather.