Everyone on board must be informed of possible risks and this information must always be available and communicated in the working language on board. 

References:

Act relating to ship safety and security (Ship Safety and Security Act)  

Regulations of 1 January 2005 No. 8 on the working environment, health and safety of persons working on board ship

Regulations of 1 January 2015 No. 1191 on a safety management system for Norwegian ships and mobile offshore units

Regulations of 16 December 2016 No. 1770 on safety management for small cargo ships, passenger ships and fishing vessels, etc.