My advice is that you throw away your gas cooker now! and get yourself an alcohol [Origo] cooker.
http://www.boatsafetyscheme.com ].
So what? Well, although these regulations have no legal effect on other waters, many marine underwriters now treat BSS 7 as the definitive standard for ANY marine LPG installation [and most marine surveyors will use BSS 7 as guidance], and insurers are likely to deny all liability in the event of fire or explosion if they subsequently find that your installation does not comply in any respect with BSS 7.
http://www.gascheckmarine.co.uk/ ], but, quite apart from the cost of a Gas Check by a Certified Gas Engineer, a quick glance at BSS 7 will almost certainly convince you that the quickest - and by far the cheapest solution - if you are starting from scratch to settle for an alcohol cooker. And if if it doesn't, then it will at least provide you with all the guidance that you need to create a safe installation.
If you do go down the alcohol cooker route, then search these forums for previous posts about their peculiarities and quirks, and about the benefits [no smell] of getting hold of de-natured alcohol rather than using meths.
sincerely
Previously Seal 22 #230 "Cecilia", nowadays
Geoff Sheddick
Parker 27/146 "Stroller'
Geoff Sheddick
Parker 27/146 "Stroller'