EMIT is the acronym for enzyme multiplied immunoassay technique, the cheapest and most common drug screen used in workplace drug testing. EMIT testing is typically used by employers as a preliminary drug screen because the test is prone to incorrect results. In general, occasional consumers (as in, once or twice per week) should have little trouble passing an EMIT test – which typically uses a 50 ng/ml cut-off for the THC-COOH metabolite – as long as they have had one or two days of abstinence prior to taking the test. Blood tests, unlike urinalysis, detect the presence illicit drugs, not inactive drug metabolites. In general, THC only remains detectable in the blood of cannabis consumers for a few hours (though low, residual levels may be detected in chronic smokers for up to 12-24+ hours if more sensitive technology is used). Because of this narrow detection window, blood tests are typically only administered in the workplace post-accident in order to estimate recent cannabis consumption. Therefore, most after-hours consumers have little to fear from a blood screen.