IMO Type 7 is identified by which conditions?

• A. 100-500 psi
• B. 25.4-100 psi
• C. 14.5-25.4 psi
• D. 23.5+ psi and -130°F or lower

Answer: (D)

The key idea is recognizing that IMO Type 7 packaging is defined by a combination of very high vapor pressure and extremely low temperatures, characteristic of cryogenic liquids. In Type 7 systems, the contents are kept at temperatures around or below the cryogenic range (-130°F or lower) and the containers must withstand a significant vapor pressure (23.5 psi or higher) as the liquid tends to rapidly vaporize when warming or during handling. That simultaneous requirement for both a very low temperature and a higher pressure is what sets Type 7 apart from other packaging types.

So the correct selection reflects this dual condition: a positive pressure of 23.5 psi or more together with a temperature at or below -130°F. The other options show either only pressure ranges without the cryogenic temperature or a different, less extreme temperature, which does not identify the cryogenic Type 7 packaging.