33 CFR §159.95

1. (a)Each device must—
   1. (1)Be free of design defects such as rough or sharp edges that may cause bodily injuries or that would allow toxic substances to escape to the interior of the vessel;
   2. (2)Be vented or provided with a means to prevent an explosion or over pressurization as a result of an accumulation of gases; and
   3. (3)Meet all other safety requirements of the regulations applicable to the type of vessel for which it is certified.
2. (b)A chemical that is specified or provided by the manufacturer for use in the operation of a device and is defined as a hazardous material in 46 CFR part 146 must be certified by the procedures in 46 CFR part 147.
3. (c)Current carrying components must be protected from accidental contact by personnel operating or routinely servicing the device. All current carrying components must as a minimum be of drip-proof construction or be enclosed within a drip-proof compartment.