Pressure indicator that retains a high pressure indication

A pressure indicator including:

• a body including:
• a cylindrical bore having a longitudinal axis;
• and
• a shoulder;
• a piston disposed at least partially in the bore, the piston including:
• a base;
• and
• a stem that extends from the base along the longitudinal axis;
• wherein the piston is located at a first axial position relative to the body when pressure of fluid acting on the base is below a threshold pressure;
• a first biasing element disposed between the base of the piston and the shoulder of the body, wherein a force of the first biasing element is overcome by pressure of fluid acting on the base at or above the threshold pressure, thereby allowing the piston to move to a second axial position relative to the body;
• a rotatable disc configured to rotate about the longitudinal axis, wherein the disc has a first rotational position when the piston is in the first axial position, wherein the rotatable disc includes a projection and the body includes an arcuate recess configured to accept the projection, wherein:
• the arcuate recess has opposite first and second ends;
• the projection is located at the first end when the rotational disc is in the first rotational position;
• and
• the projection is located at the second end when the rotational disc is in a second rotational position;
• and
• a second biasing element configured to urge the disc to the second rotational position when the piston is in the second axial position.

A method for indicating that a pressure level of fluid in an interior of a pressure vessel has exceeded a threshold pressure level, the method including:

• presenting a first visual indication when the pressure level of fluid in the interior of the pressure vessel is below the threshold pressure level;
• presenting a second visual indication, different from the first visual indication, when the pressure level of fluid in the interior of the pressure vessel has increased to a level above the threshold pressure level;
• and
• retaining the second visual indication even after the pressure level of fluid in the interior of the pressure vessel has decreased to a level below the threshold pressure level.