A pressure vessel, comprising: a tank, including: i) a tank liner fabricated from thermoplastic material; ii) a valve fitting assembly; and iii) an outer reinforcing layer disposed on the tank liner, the outer reinforcing layer defining at least a portion of an outer surface of the tank; and a protective jacket adapted to surround and engage the tank, the protective jacket includes: i) an upper support rim defining a top aperture, wherein the valve fitting assembly extends through the top aperture, and said aperture creates a first airflow opening around the valve fitting assembly between the upper support rim and the valve fitting assembly; ii) a lower support rim having a second airflow opening therethrough; and iii) a substantially cylindrical wall connecting the upper support rim to the lower support rim, the wall defining an inner surface disposed radially outwardly from the outer surface of the tank, the inner surface of the wall and the outer surface of the tank cooperating to define a flow channel in fluid communication with the first airflow opening and the second airflow opening, wherein the first and second airflow openings and flow channel are adapted to permit a convective flow to pass therethrough to facilitate heat transfer between the tank and an environment in which the pressure vessel is situated. a tank, including: i) a tank liner fabricated from thermoplastic material; ii) a valve fitting assembly; and iii) an outer reinforcing layer disposed on the tank liner, the outer reinforcing layer defining at least a portion of an outer surface of the tank; and i) a tank liner fabricated from thermoplastic material; ii) a valve fitting assembly; and iii) an outer reinforcing layer disposed on the tank liner, the outer reinforcing layer defining at least a portion of an outer surface of the tank; and a protective jacket adapted to surround and engage the tank, the protective jacket includes: i) an upper support rim defining a top aperture, wherein the valve fitting assembly extends through the top aperture, and said aperture creates a first airflow opening around the valve fitting assembly between the upper support rim and the valve fitting assembly; ii) a lower support rim having a second airflow opening therethrough; and iii) a substantially cylindrical wall connecting the upper support rim to the lower support rim, the wall defining an inner surface disposed radially outwardly from the outer surface of the tank, the inner surface of the wall and the outer surface of the tank cooperating to define a flow channel in fluid communication with the first airflow opening and the second airflow opening, wherein the first and second airflow openings and flow channel are adapted to permit a convective flow to pass therethrough to facilitate heat transfer between the tank and an environment in which the pressure vessel is situated. i) an upper support rim defining a top aperture, wherein the valve fitting assembly extends through the top aperture, and said aperture creates a first airflow opening around the valve fitting assembly between the upper support rim and the valve fitting assembly; ii) a lower support rim having a second airflow opening therethrough; and iii) a substantially cylindrical wall connecting the upper support rim to the lower support rim, the wall defining an inner surface disposed radially outwardly from the outer surface of the tank, the inner surface of the wall and the outer surface of the tank cooperating to define a flow channel in fluid communication with the first airflow opening and the second airflow opening, wherein the first and second airflow openings and flow channel are adapted to permit a convective flow to pass therethrough to facilitate heat transfer between the tank and an environment in which the pressure vessel is situated.