[7][3] Ships typically calculate their UKC to meet criteria for ports to minimise the risk of maritime incidents.
[7] At a basic level, it is typically calculated in metres using the formula:[1] Ship masters and deck officers can obtain the depth of water from Electronic navigational charts.
[5] More dynamic or advanced calculations include safety margins for manoeuvring effects and squat.
[11] For US waters, the US Code of Federal Regulations require ships and their masters to calculate UKC based on the ship's deepest navigational draft.33 CFR 157.450 The regulations require the master to discuss the UKC calculation with the maritime pilot as the ship approaches US ports/waters.33 CFR 157.450 The Australian Maritime Safety Authority state that maintaining adequate UKC is important for safe navigation in the Torres Strait.
[13] In 2019, the UK Marine Accident Investigation Branch found that indequate UKC contributed towards the grounding of the ro/ro freight ferry MS Stena Performer.