Swiss and international legal framework (licensing, registration, environmental rules)
The legal questions are the easiest marks in the exam and the ones most often lost, because candidates answer by habit rather than by the rule.
Licence and documents
Under the BSO (Binnenschifffahrtsverordnung) a Führerausweis is required for craft above the exemption limits - the well-known thresholds are 15 m² of sail area and 4.4 kW (about 6 PS) of engine power, below which no licence is needed. Carry the licence, the registration document, proof of liability insurance and, where fitted, the radio licence. Registration (Immatrikulation) is handled by the cantonal shipping office, which issues the number carried on the hull.
Insurance and responsibility
The BSO sets a compulsory minimum liability cover (currently CHF 2 million). The skipper remains responsible for boat and crew even when someone else is at the helm; letting an unlicensed person drive is an offence for both.
Alcohol
The limit is 0.5 per mille (0.05 % BAC), lower for professional skippers. Refusing a breath or blood test is treated like being over the limit.
Environment
No oil or sewage discharge; use pump-out stations; keep bilge water clean with a filter pad; respect protected zones, reed beds and bird reserves; keep wake low near shore, moorings and swimmers; observe noise limits and the local lake regulation (Seereglement).
International layer
COLREG applies at sea; inland waterways follow CEVNI and, on the Rhine, the Rhine police regulations; Lake Constance has its own Bodensee-Schifffahrts-Ordnung. Swiss lakes combine the BSO with cantonal rules.
Duties
Give assistance to persons in danger without seriously endangering your own vessel; report accidents involving injury or significant damage; do not leave the scene.
Worked example
A friend without a licence takes the helm while the owner sits in the cockpit. If stopped, the helmsman is prosecuted for driving without a licence and the owner for allowing it, and the insurer may reduce cover. Correct answer: the owner stays responsible and must not hand over the helm.
Traps
Assuming a rental boat needs no licence; assuming a foreign licence is valid indefinitely; ignoring cantonal lake rules; leaving the insurance document ashore.