Samples for bacterial analysis shall be collected in bottles which have
been cleansed with great care, rinsed in clean water, and sterilized
with dry heat for at least one hour and a half at 170° C., or in the
autoclav at 15 lbs. (120° C.) for 15 minutes or longer after the
pressure reaches 15 lbs.
Great care must be exercised to have the samples representative of the
water to be tested and to see that no contamination occurs at the time
of filling the sample bottles.