Patent ID: 8759082

Claim:
An analytical instrument comprising an O 2 sensor and a microprocessor in electrical communication with the sensor, wherein the instrument is effective for (i) periodically ascertaining an O 2 concentration of an incubating sample taken from an object, (ii) determining a time period t Threshold from a time t o at which incubation of the sample commenced to a time at which an ascertained O 2 concentration for the sample first falls below a threshold value, (iii) correlating t Threshold to a viable aerobic microbe count in the sample prior to incubation, utilizing the linear equation: y=mx+b (Eq. 1) wherein: x=logarithm of the viable aerobic microbe count per unit weight of, volume of or area swabbed to obtain a sample at t o y=t Threshold x-intercept=(−b/m)=an estimated or experimental value for the logarithm of the minimum viable aerobic microbe count at t o in a sample effective for causing the sample to reach t Threshold substantially instantaneously upon commencement of incubation, and m (slope)=(y 2 −y 1 )/(x 2 −x 1 ) wherein: x 1 and y 1 are ascertained experimentally by establishing t Threshold for a sample taken from an object having a known x, and x 2 and y 2 are values of x and y at the x-intercept (−b/m, 0), and (iv) transmitting a correlated value of x to a peripheral device.