TIERS-C RATING SYSTEM
The Triple S Inspection and Evaluation Rating System for Cleanliness
(TIERS-C)
The TIERS-C system provides a comprehensive tool for assessing and “judging” the overall cleanliness of a building, room, surface or item. While the system will apply slightly differently depending on what is being assessed, the system is based on four color-coded tiers representing a range from clean to unclean or dirty. The four color-coded tiers also correlate to numerical scores ranging from 0-10.
TIERS-C is based primarily on subjective observation — or what one sees, feels,and/or smells. The system; therefore, relies to a certain extent on one’s intuition or “gut.” In some cases, however, objective measurement is recommended; specifically, the use of UV/fluorescent gel marking. ATP meter testing may also be utilized in special cases.**
The four tiers are outlined below. Note that not all descriptions, parameters and metrics will apply to all rooms, surfaces and items.
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Green represents the optimal level. The facility, room, surface or item is very clean and in a “like-new” condition.

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Blue represents the good/very good level. The facility, room, surface or item is clean although there may be some noticeable signs that it is not optimal.

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Yellow represents the fair level. The facility, room, surface or item is best judged as neither trily clean nor really dirty.

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Red represents the poor level. The facility, room, surface or item is not clean. It can even be claimed it has been neglected.


