UKC: what SIRE 2.0 inspectors ask and find
Under-keel clearance is a favourite with inspectors because it joins policy, calculation and practice: the company rule, the figures for this port and the echo sounder alarm.
Do this before the inspector arrives: Print the UKC calculation for this port and know the company policy.
What the inspector wants to see
- Company UKC policy
- UKC calculation for this port and the last one
- Echo sounder alarm set to match the policy
Questions inspectors ask about UKC
What must the safety depth calculation include?
CATZOC allowance (+) and height of tide (-), the same as the UKC calculation (NP232 para 12.12). Leaving them out was flagged.
What was your UKC when passing over a pipeline marked on the ECDIS?
Inspectors expect you to know it and show it in the passage plan.
What mistake is often made when printing tides from tidal software?
Not applying the zone time, so the tide is not in local time.
Does the company UKC policy cover the ship at anchor?
Inspectors asked where UKC at anchor is covered in the UKC policy, and about the policy in general.
What are 'confined waters' for squat calculations?
Depth under twice the ship's draught, or ship's beam greater than one-fifth of the waterway width.
What do CATZOC 'D' and 'U' mean?
Survey accuracy is graded A1, A2, B, C, D and U. A1 is best and D is worst; U means unassessed, so accuracy cannot be judged.
There are 9 UKC questions in NilObs, with spaced repetition so the ones you miss come back. Practise them free.
Real UKC observations, and how to avoid them
Operator procedure applied CATZOC and tide corrections only to UKC calculations, not to the safety depth setting.
Avoid it: Allow for CATZOC accuracy and tide when setting ECDIS safety depth, not just for UKC.
Navigation procedures did not require the ship's UKC calculation to be reviewed with the pilot during the Master/pilot exchange.
Avoid it: Discuss and agree the UKC calculation with the pilot during the Master/pilot exchange.
There was no evidence the ship's UKC calculation was discussed with the pilot as the BPG expects; the officer said it was mentioned but could not show it.
Avoid it: Record the UKC discussion on the pilot card or exchange checklist so it can be shown.
Who answers for UKC
Master, Second Officer, Port Captain. NilObs picks the questions and the daily drill for your role.
Rehearse UKC before your next inspection.
Start free
Start free
Other topics
ECDIS9 observationsRadar4 observationsPassage planning5 observationsGMDSS10 observationsAlarm & power-fail tests3 observationsEquipment tests vs PMS23 observationsDocuments & SMS51 observationsRest hours & drills17 observationsDefect reporting29 observationsWatchkeeping16 observationsSteering2 observationsLSA & FFA31 observationsEngine room50 observationsCargo69 observationsPIQ accuracy46 observationsPermits & RA11 observationsEmergency equipment43 observationsGas testing & enclosed space61 observationsPPE & personal safety21 observationsPollution prevention27 observationsSecurity & cyber11 observationsTraining & certificates25 observationsHull & condition31 observationsMooring & access59 observations