Two Types Totally Enclosed Life Boat

The fully enclosed lifeboat has only two forms in my understanding:

1, Ordinary fully enclosed lifeboat, this lifeboat does not contain sprinkler system, air system, mostly used for passenger ships, bulk carriers, etc.

2, Fire-resistant fully enclosed lifeboat, this lifeboat has sprinkler system, air system, mostly used for flammable freighters such as oil tankers and oil platforms.

If there are three forms, there is also a fully enclosed free-fall lifeboat, which can quickly leave the mother ship. The boat frame is also different from the previous two lifeboats.