MPN Table
(Most Probable Number)

Eijkmann-Durham Tubes for E. coli
Fraction of tubes
having NO bubble AVERAGE number
E. coli in the sample
put into each tube
NONE *
0.05 3.0
0.10 2.3
0.15 1.9
0.20 1.6
0.25 1.4
0.30 1.2
0.35 1.0
0.40 0.92
0.45 0.80
0.50 0.69
0.55 0.60
0.60 0.51
0.65 0.43
0.70 0.36
0.75 0.29
0.80 0.22
0.85 0.16
0.90 0.11
0.95 0.051
ALL §

Eijkmann-Durham Tubes for E. coli
Fraction of tubes having NO bubble	AVERAGE number E. coli in the sample put into each tube
NONE	*
0.05	3.0
0.10	2.3
0.15	1.9
0.20	1.6
0.25	1.4
0.30	1.2
0.35	1.0
0.40	0.92
0.45	0.80
0.50	0.69
0.55	0.60
0.60	0.51
0.65	0.43
0.70	0.36
0.75	0.29
0.80	0.22
0.85	0.16
0.90	0.11
0.95	0.051
ALL	§

* Too concentrated: either dilute your sample more than 10-fold, or add smaller volumes to your E-D tubes.

§ Too dilute: either add a higher concentration, or add a larger volume of sample to your E-D tubes.