California Code of Regulations
Title 22 - Social Security
Division 2 - Department of Social Services-Department of Health Services
Part 2 - Health and Welfare Agency-Department of Health Services Regulations
Subdivision 6 - Preventive Medical Services
Chapter 9 - Tuberculosis Examination
Article 3 - Tuberculosis Examination
Section 41309 - Reading and Recording a Reaction to an Approved Skin Test

(a) When the standard skin test is administered to a person, the reaction to the test shall be read by a physician or his/her designee between 48 and 72 hours after administration of the test. The reaction shall be recorded in millimeters of greatest induration.

(b) When the multiple-puncture test is administered to a person, the reaction to the test shall ordinarily be read between 48 and 72 hours after administration of the test. Readings up to seven days after administration are permissible in some multiple-puncture tests. Manufacturer's recommendations should be followed. A person who has any kind of reaction other than vesicular shall be retested with the standard skin test.