Within Ships Equipment Decree – Article 7.05, paragraph 1-2 – Lifebuoys and lifejackets
1. There must be at least three lifebuoys on a ship. In ready-to-use condition, they must be on suitable places on deck. They may not be attached to the ship. For motor vessels with a length of less than 40 m, two lifebuoys are sufficient. At least one lifebuoy must be provided with a throw line of sufficient length.
2. Lifebuoys must comply with the following rules:
a) the carrying capacity in fresh water must be at least 7.5 kg;
b) they must be made of suitable material and be resistant to oil, oil products and temperatures up to 50 ° C;
c) they must be clearly visible in the water due to their color;
d) the own weight must be at least 2.5 kg; at Sea 4 kg
e) the internal diameter must be at least 45 cm and at most 50 cm;
f) they must be provided with an all-round grip line;
(g) they must be of a type approved by the Inspector General.