The ColRegs (IRPCS 1972) are the navigation rules that govern every vessel in every international water. Not racing rules, not local bylaws — these are the rules that carry legal force at sea. Four practical guides for offshore sailors.
The ColRegs hierarchy of vessels — NUC, RAM, constrained by draft, fishing, sailing, power — what stand-on and give-way actually require, and why a sailboat under sail does NOT have right of way over a large commercial vessel.
Running lights explained — red, green, stern, steaming, anchor, and the special rules for sailing vessels, fishing vessels, and small craft. How to read another vessel's lights to determine its course and type.
Fog signals, maneuvering signals, and the five short blasts you must never ignore. Sound signals under ColRegs remain legally required even when VHF and AIS are aboard.
The 2-minute bearing rule, why large ships cannot stop or see you, the constant bearing / decreasing range test, and how to make your course alterations obvious enough that the other vessel knows you have responded.