3 



1 (r) Siibmeisiblcs certified by the Americiin Bureau of 



2 Shipping or other classification society approved by the Sec- 



3 retary may be accepted as having met sections 3(a) (1) 



4 and (2). 



5 (d) The Secretary may by regulation exempt manned 



6 submersible vessels from the requirements of this Act and 

 T any regulation issued thereunder if he detemiines tliat the 



8 maimed submersible vessel is being constructed or operated 



9 for developmental, experimental or research work. 



10 Sec. 4. (a) The Secretarj^ may group submersible 



11 vessels into classes on the basis of similarity of characteristics 



12 or of utilization, or both. 



13 (b) The owner or the builder of a submersible vessel 

 li subject to any regulation issued under section 3 of this Act 

 15 shall apply to the Secretary for a certificate of inspection. 

 1(> If the Secretary finds, after inspection, that the submersible 

 n vessel is properly etiuipped and safe to be operated in accord- 



18 ance with the requirements of this Act and the regulations 



19 hereunder, he shall issue a certificate of inspection. The Sec- 



20 retary may prescribe in a certificate of inspection the dura- 



21 tion thereof and such other terms, conditions, and limita- 



22 tions as are required in the interest of safety. 



23 (c) The Secretary may, from time to time as he deems 



24 necessary, reinspect any submersible vessel for which a 



25 certificate of inspection has been issued. If the Secretary 



726 



