Section 325.5006. Definitions C.

(1) "Calendar quarter" means not less than 12 consecutive weeks nor more than 14 consecutive weeks. The first calendar quarter of each year shall begin in January and subsequent calendar quarters shall be arranged so that a day is not included in more than 1 calendar quarter nor is a day in any 1 year omitted from inclusion within a calendar quarter. A licensee or registrant shall not change the method observed by him of determining calendar quarters for purposes of these rules except at the beginning of a calendar year.

(2)    "Coefficient of variation" means the ratio of the standard deviation to the mean value of a population of observations.   It is estimated using the following equation:

 s

1 é n

1

(X - X )2 ù 2

C =     =     êå      i                  ú

X       X êë i=1

n -1     úû

where:   s    = Estimated standard deviation of the population.

X     = Mean value of observations in sample.

Xi    = i th observation in sample.

n     = Number of observations in sample.

(3)     "Controlled area" means a restricted area.

(4)     "Cooling curve" means the graphical relationship between heat units stored and cooling time.

(5)     "Curie" means the quantity of radioactive material which decays at the rate of 3.7 x 1010 disintegrations per second (dps). Commonly used submultiples of the curie (Ci) are the millicurie (mCi), the microcurie (μCi) and the nanocurie (nCi).  One millicurie = 0.001 curie =

3.7 x 107 dps.  One microcurie = 0.000001 curie = 3.7 x 104 dps.  One nanocurie = 0.000000001 curie = 37 dps.  Curie is the special unit of measurement of radioactivity.

History:  1954 ACS 85, Eff. Dec. 3, 1975; 1954 ACS 98 Eff. Mar 9, 1979.