By a method measuring the total ATP (Adenosine Tri-phosphate) cleanness of products through the procession of meat processing instruments was evaluated. This method was much more sensitive in detecting contamination sources (food residual dregs and microorganisms) than the conventional method, providing a useful contamination index. Because of rapidity and simplicity, the method is suitable for monitoring HACCP (Hazard Analysis Critical Control Point) system and for applying to job sites due to the easier maintenance of PP (Prerequisite Programs). Furthermore, it is effective in drawing up SSOP (Sanitation Standard Operating Procedures).