Air independent power systems specially designed for underwater use, as follows: (a) Brayton or Rankine cycle engine air independent power systems having any of the following: 1. Chemical scrubber or absorber systems, specially designed to remove carbon dioxide, carbon monoxide and particulates from recirculated engine exhaust; 2. Systems specially designed to use a monoatomic gas; 3. Devices or enclosures, specially designed for underwater noise reduction in frequencies below 10 kHz, or special mounting devices for shock mitigation; or 4. Systems having all of the following: a. Specially designed to pressurise the products of reaction or for fuel reformation; b. Specially designed to store the products of the reaction; and c. Specially designed to discharge the products of the reaction against a pressure of 100 kPa or more;