Tuberculin PPD RT23 SSI Dosage/Direction for Use

A dose of 0.1 mL of PPD RT23 is injected intracutaneously in the middle-third of the forearm, since a weak reaction near the wrist of elbow. A 1 mL graduated syringe with a short-beveled 25–26 gauge (0.5 x 10 mm) is recommended for administration of the skin test. As the liquid is injected, a small round wheal or papule of 8-10 mm in diameter should be formed, remaining for about 10 minutes.
Reading: During 48–72 hours after injection, an induration, possibly surrounded by area of redness, can be expected in positive reactors. Measure only the induration (skin reaction) about 3 days after the application. The skin reaction can be palpated as flat, uneven, slightly raised induration which should be measured with a clear, flexible, plastic ruler.
A positive reaction to Tuberculin PPD RT23 is defined as an induration having a diameter of 6 mm or more.