The study tests a new way to check for drugs using fingerprints. "Operators" will use the Intelligent Fingerprinting Drug Screening System, while "donors" will give fingerprint sweat samples after taking different doses of codeine sulfate (0, 30, or 60mg). Operators will not take any drugs. The study will measure how well this new method works compared to a proven lab technique called LC-MS/MS, which stands for liquid chromatography-mass spectrometry/mass spectrometry, a complicated term for a very accurate way to find drugs in the body.

To participate, you must be a healthy adult (male or non-pregnant female) between 18-65 years old. If you have certain health conditions or history of substance abuse, you may not be able to join. Participants should not have taken any experimental drugs recently.

• **Length**: Participants will be randomized into groups and tested with different doses of codeine.
• **Visits**: The study involves giving fingerprint samples for testing.
• **Risks**: Participants must be healthy with no significant medical issues.