Interpreting the Fire Protection requirements of EN ISO 9094:2017

Prior to the 2017 edition, the harmonised fire protection standard consisted of 2 parts: 1 for boats longer than 15m and one for shorter craft.  Neither section had any words on the topic of fire detection. The new edition comes in one single document and says the following:

The above is the full text of section 5. You will note that it does not ask for a detector: only a means to alert the crew. i.e. an alarm. One could ask how one can raise an alarm without a detector but perhaps a human is a detector and can raise an alarm?  It does not say how many detectors are required and where they should be located.  It says that fire detection devices should have an audible alarm but what if the boat has a central alarm or is this not allowed?

So the standard raises more questions than it answers and when discussed at RSG, it became apparent that the Notified Bodies had a range of interpretations from 1 detector in every single cabin through to one in each accommodation area. Some wanted detectors in all spaces with potential sources of ignition and others only in accommodation spaces. It took a while to reach an agreement but eventually RFU (Recommendation For Use) #300 was issued.  This states:

The latter statement implies that there are no requirements to check the audible sound levels in compartments so long as a detector/alarm compliant with an ISO standard is fitted in the accommodation space.

Reputable manufacturers of detectors provide good information with drawings showing the recommended locations of detectors. Here is an example from a KIDDE user manual.  This is intended for buildings but the sleeping and non-sleeping spaces of boats and houses suffer equally in fires

Unless you wish to fit a detector in every single cabin (white circles), the best location for a detector is NOT inside a sleeping space. Since the most likely source of a fire is in a galley or engine room, some distance from the accommodation, if the smoke must reach the inside of a sleeping cabin before triggering the alarm, it is far too late.  So it is best to have a detector in corridors leading to accommodation spaces (black circles) between accommodation and other spaces. Since the detectors are to alert the people onboard, there is no requirement to fit one inside an engine space.