Crack pipes are generally very short because the smoke can become inactive very quickly. Second hand smoke floating around a room is already inactive. In order to fail, you have to smoke the crack yourself and take a urine test within 3 days or so.

Heroin is diacetylmorphine. It is considered a pro-drug (i.e. It sets the stage...) for morphine. Once heroin hits the brain it is converted into morphine, 6-monoacetylmorphine, and 3-MAM. Other drugs that contain morphine as a metabolite are morphine and codeine. 6-MAM is a metabolite unique to heroin and if it's in your urine, it's indisputed … Read more

Codeine is slightly weaker, but yes, they will both get the job done. 15 mg codeine and 5 mg hydrocodone (Vicodin) will have the same painkilling effect, though unless you have no tolerance whatsoever those low doses will do nothing for a subjective high.