But things get much murkier when it is a task order for a defense customer issued against a civilian IDIQ. There are about a dozen protests pending at GAO right now that fall into that crossover category, where a defense agency used a GSA contract such as Alliant or OASIS to hire a contractor.
purified protein derivative (PPD). [pyoÌoÌâ²rifÄ«d]. a dried form of tuberculin used in testing for past or present infection with tubercle bacilli. This product is usually introduced into the skin during such tests and may produce a tuberculin reaction (wheal) within 48 to 72 hours.
The test is done by putting a small amount of TB protein (antigens) under the top layer of skin on your inner forearm. If you have ever been exposed to the TB bacteria (Mycobacterium tuberculosis), your skin will react to the antigens by developing a firm red bump at the site within 2 days.The TB antigens used in a tuberculin skin test are called purified protein derivative (PPD). tuberculin skin test is done to find people who have tuberculosis (TB), including: 1  People who have been in close contact with someone known to have TB. 2  Health care workers who are likely to be exposed to TB. 3  People with TB symptoms, such as an ongoing cough, night sweats, and unexplained weight loss.