Here in the US - anybody can be a marine surveyor (SAMS and NAMS are accreditation societies)....but down-under - the dispensing of marginal maritime advise is regulated by the government...
From Queensland, Australia regs...
TRANSPORT OPERATIONS (MARINE SAFETY--QUALIFICATIONS FOR ACCREDITATION FOR SHIP DESIGNERS, SHIP BUILDERS AND MARINE SURVEYORS) STANDARD 1998 -
SECT 8 Marine surveyors--specific requirements
8.(1) A person who wants to be accredited as a marine surveyor must have--
(a) at least 10 years experience; or (b) at least 5 years experience and 1 of the following qualifications--
(i) a certificate as a class 1 or 2 marine engineer or master;
(ii) a degree in naval architecture;
(iii) a degree in marine engineering;
(iv) a diploma, associate diploma or certificate in naval architecture or shipbuilding;
(v) trade qualifications as a shipwright or boat builder; (vi) other educational, sea going or trade qualifications the person satisfies the chief executive are equivalent to, or better than, the qualifications mentioned in subparagraphs (i) to (v).
(2) A person who wants to be accredited as a marine surveyor for part of a ship must have--
(a) a trade qualification as an electrician; and (b) at least 2 years post qualification experience.
(3) In this section--
"experience" means appropriate experience with demonstrated competence in surveying ships, or parts of ships, of the category for which the accreditation is sought.