Community QuestionSeen on 7 CBTs

What are some methods to purify water?

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Answer

~Purifying with a commercial micro filter ~Chemically treating water with chlorine or iodine ~Boiling vigorously for at least one minute

2 of 7 indexed CBT versions give this answer·Answer index rebuilt Aug 16, 2026

VERIFIED AGAINST THE OFFICIAL SOURCE

Boiling is the safest method for purifying water. Bringing water to a rolling boil for one minute at sea level will kill all waterborne pathogens. If above 8,000 feet, the boiling time should be extended to 3 minutes.

ATP 3-50.21, Survival (18 September 2018), Ch. 3 Water, para 3-41

The indexed versions don't agree on this one

This question appears on 7 CBT versions we've indexed, and they don't all give the same answer. Exam editions change and answer keys get re-cut, so more than one of these was correct on the test it came from. Here is each of them, and how many versions give it.

2 of 7 versionsmost versions

~Purifying with a commercial micro filter ~Chemically treating water with chlorine or iodine ~Boiling vigorously for at least one minute

Code Of Conduct Sere · Sere Code Of Conduct

1 of 7 version

Purifying with a commercial micro filter Boiling vigorously for at least one minute Chemically treating water with chlorine or iodine

Blood Chit Sere

1 of 7 version

Boiling vigorously for at least one minute (correct) Chemically treating water with chlorine or iodine (correct) Purifying with a commercial micro filter (correct)

Jko Direct

1 of 7 version

1.Chemically treating water with chlorine or iodine 2.Purifying with a commercial micro filter 3.Boiling vigorously for at least one minute

Jko Sere 100.2 Pre Test Answers

1 of 7 version

Boiling vigorously for at lease one minute Chemically treating water with chlorine or iodine Purifying with commercial micro filter

Score Sere

1 of 7 version

-Purifying with a commercial micro filter -Chemically treating water with chlorine or iodine -Boiling vigorously for at least one minute

Sere 100.2 Military Pretest Answers

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