In this method, an air sample is drawn through a filter for some time. The activity on the filter is then allowed to decay for at least 40 minutes, but less than 90 minutes. The activity on the filter is then counted in the TM372. The decay and counting times should be chosen so that the time between the end of sampling and the middle of counting is between 40 and 90 minutes.

This method is sometimes used by inspectors in underground mines because it is possible to take a series of samples in a short time and then evaluate them on surface. When results are needed quickly, the Rolle method is more practical and is more commonly used. 

   Notes:
   

	Input Fields	Calculated Fields
Enter the sample pump flow rate (L/min):
Enter the efficiency of the TM372 counter (or equivalent):
Self Absorption Factor
Enter the background count rate of the counter (CPM):
Enter the sampling time (min):			Time between end of sample and middle of count (min).
Enter the time interval between sample start time (the time you started the pump) and count start time:			Kusnetz factor
Enter the count time (min):
Enter the gross counts:			WL Kusnetz Method