Patent ID: 7578170

Claim:
An instrument comprising: (a) a needle having a lumen operable for perforating a hermetically sealed packaging so as to place the lumen of the needle in fluid communication with a retention chamber defined by the packaging; (b) a vacuum pump in fluid communication with the lumen defined by the needle effective for evacuating gaseous content from the hermetically sealed packaging to form an evacuated retention chamber; (c) a mass flow rate sensor in sealed fluid communication with the lumen defined by the needle for sensing a mass flow rate pulled through the lumen from the evacuated retention chamber by the vacuum pump and transmitting a mass flow rate signal; (d) a first pressure sensor operative for sensing an external pressure on the hermetically sealed packaging and transmitting an external pressure signal; (e) a second pressure sensor for sensing pressure within the retention chamber defined by the packaging and transmitting an internal pressure signal, (f) a display device; (g) a user input device; (h) a memory device for receiving and storing (1) a value for the fluid viscosity of the external gas, (2) a value for the packaging wall thickness, and (3) a value for at least one packaging seal length; and (i) a processor interconnected and programmed to (1) receive the mass flow rate signal, (2) receive the external pressure signal, (3) receive the internal pressure signal, (4) communicate with the memory device to obtain the fluid viscosity value, packaging wall thickness value and packaging seal length value, (5) calculate a first hole size value for a hole through the packaging wall utilizing Poiseuille's Law and the value for the packaging wall thickness, (6) calculate a second hole size value for a hole through at least one seal utilizing Poiseuille's Law and the value for at least one seal length, and (7) display at least one of the first and second hole size values.