Pressure indicating device

A pressure indicating device for recording and isolating a leak of pressurized gas from a closed valve of a gas cylinder, comprising:

• a housing defined, in part, by an upper housing portion and a lower housing portion, the upper housing portion characterized by an inner channel extending therethrough, and the lower housing portion characterized by a gas flow channel extending therethrough, the lower housing portion disposed within a user port of the cylinder valve;
• a movable pin disposed within the interior channel of the upper housing portion;
• a solid diaphragm in a neutral state disposed between the upper and the lower housing portions, the diaphragm having a bottom surface and a top surface, the top surface of the solid diaphragm oriented towards the pin, and the bottom surface of the solid diaphragm oriented towards the lower housing portion, wherein the bottom surface is in fluid communication with the gas flow channel, the diaphragm sealed in place along an edge thereof;
• a seal extending along an outer surface of the upper housing through which the pin is configured to extend when said pin is in the activated state;
• wherein the solid diaphragm is configured to flex from a neutral state to an activated state towards the pin in response to a predetermined activating pressure exerted against at least a portion of the bottom surface of the diaphragm, the diaphragm in the activated state flexing a sufficient amount against the pin so that a portion of the top surface of the diaphragm urges the pin from within the inner channel a sufficient axial distance through the upper housing so as to move the pin externally of the housing, thereby allowing the pin to pierce the material and visually indicate the leak of the pressurized gas from within the interior volume of the cylinder.