It does depend on the wreck and the level of penetration.
Depth, overhead limitations and or entanglement issues are the big determining factors.
Depth, overhead limitations and or entanglement issues are the big determining factors.
Depends on the wreck. At Catalina Island, there's a tiny sailboat that was sunk on purpose (I think). It has a hole in the side big enough for one person to go in and out. I seriously doubt that you'd need technical skills to crawl into this thing and come back out.
What is it they often say about the exception?
BTW, I wouldn't personally consider crawling into a small hole to be 'penetration'. It is, however, a "getting stuck underwater" hazard.