Issue link: https://hi.iaq.net/i/639237
ISSA Clean Standard: Measuring the Effectiveness of Cleaning 10 5. Quantitative Measurement of Cleaning Effectiveness 5.1. Understanding the ATP-RLU Table The effectiveness of the cleaning processes and products used at a facility may be determined by comparing actual ATP measurements with the table set forth in this section. The table below sets forth ATP-RLU limits or ranges for specific ATP metering systems. The limits, ranges, and verbal descriptions reflect the results that can be reasonably a ained using cleaning methods readily available today. The limits and ranges are, therefore, based on what can reasonably be expected to be achieved as demonstrated by the research on which the Clean Standard is based. Specifically, for the Charm Sciences NOVALUM and the 3M Uni-Lite NG devices, "Effective Cleaning" represents the top 50% of the thousands of ATP measurements, "Needs Improvement" represents values that fall in the 50th to 75th percentile of all research results, and "Ineffective Cleaning" limits are those that fall in the bo om 25% of the results from the research. In regard to the Hygiena SystemSure Plus device, "Effective Cleaning" is achieved when the ATP measurements are lower than the 75th percentile, and "Ineffective Cleaning" results when measurements exceed the 90th percentile, with "Needs Improvement" representing the range between the two. The Hygiena system was treated differently for these purposes because of: 1) observed variance associated with the use of this system during the original research (although it was still within acceptable ranges for reliability) and 2) field testing that revealed the ranges currently set forth in the table below were reasonable and achievable. 5.2. Using the ATP-RLU Table The table below sets forth ranges for each of the levels of "cleaning effectiveness" for hard, non- porous surfaces commonly found within commercial and institutional facilities. These include desks or worktables, restroom stall doors, cafeteria or breakroom tables, and sink surrounds in restrooms. Separate ranges are provided for three ATP metering systems—Charm Sciences NOVALUM, 3M Uni- Lite NG, and Hygiena SystemSure PLUS. It is recommended that facilities strive to provide "Effective Cleaning" for the HTP surfaces, based on ATP measurements for the metering system being used. i. ATP Metering System. It is imperative to use the values that match the specific ATP Metering system that is being used to take the measurements. DO NOT use the ATP/RLU values for a different ATP system as their scales vary widely. ii. Porous Surfaces. ATP meter systems should not be used on porous, soft, or otherwise distinctly different surfaces or material types. Surfaces such as carpeted floors/walls, and grout cannot be measured using ATP meters.