Richie said:
I'm new to live steam in G scale and have 2 second hand Accucraft loco's both of which came with out any certification i know from my dad's 5" gauge loco's that you have a boiler certifiate's did ask when i got the loco's should they have a certificate but was told no they don't come with any .
Originally your locomotive would have come with 2WP certification for both boiler and gas tank. Unless the boiler is damaged then they will be perfectly safe. I would conduct a steam test on these locos. First of all check that the boiler blows off at working pressure and that there are no leaks on boiler fittings. Then leave the thing blowing off and ensure that the safety valve can expel all the steam that the burner can make. You do not require certificates for these tiny boilers, and if you are a member of an association then you are covered in terms of 3rd party insurance.
If you want to get your loco hydraulically tested, then I am sure that your Dad's club can arrange this for you - if not go to whichever association you are a member of. In terms of pure safety however, you have no worries. There is a safety factor of between seven and ten times on these little copper pressure vessels and, to put this in perspective, the safety factor on full size helicopters is 1.5.