Mantoux Tuberculin Skin Test
From The Centers for Disease Control and Prevention
Division of TB Elimination

Test Administration: Give 0.1 ml of 5 Tuberculin Units PPD intradermally. (Administration examples below.)

All tests should be read between 48 and 72 hours. If more than 72 hours has elapsed and there is not an easily palpable positive reaction, repeat the test on the other arm and read at 48 to 72 hours after the second administration.

Measure the induration - not erythema. Measure and report results in millimeters of induration.

All persons with positive reactions should be evaluated for preventive therapy, once TB disease has been ruled out.

Negative Reactions

For each of the categories, reactions below the cutting point are considered negative.

Positive Reactions

15 or more millimeters induration is always considered positive. Specifically, it is positive for persons with no risk factors for tuberculosis.

10 or more millimeters induration is considered positive for high risk groups, such as:

5 or more millimeters induration is considered positive for the highest risk groups, such as:

Needle Too Deep



Needle Too Shallow



Inserted Properly



Measure the Diameter



Positive Reaction: 18mm






Last updated:  Aug 14, 1998