Record the exact measurement in millimeters of induration on the Mantoux Tuberculin Skin Test Record Form. … Record the date and time the test was read, the name and signature of the person who read the skin test, and the presence or absence of adverse effects (i.e., blistering, redness, and swelling)

How many mm indicates a positive TB test?

An induration of 15 mm or more is considered positive in: Always considered positive in any person. Healthy individuals without any risk factors for TB.

What is considered a positive TB test?

In a healthy person whose immune system is normal, induration greater than or equal to 15 mm is considered a positive skin test. If blisters are present (vesiculation), the test is also considered positive. In some groups of people, the test is considered positive if induration less than 15 mm is present.