d. Timed urine: Time required may be 2, 12, or 24 hour collections. The time period begins after the client urinates and ends with a final voiding at the end of the time period. The client voids into a clean receptacle, and the urine is transferred to the special collection container, which often contains special preservatives. Each specimen must be free of feces and toilet tissue. Missed specimens make the whole collection inaccurate. Check with agency policy and the laboratory for specific instructions.