Small public areas such as lobbies and corridors can be easily cleaned by mopping daily with warm water and an all-purpose liquid cleaner that is either neutral or mildly alkaline, i.e. pH 7-9.
Large public areas such as shopping centers, malls and auditoriums may be cleaned with self propelled scrubbing machines using the following suggestions:
1. For daily cleaning, a detergent with a pH of 7-9 should be used.
2. For heavy cleaning, an organic acid cleaner with a pH of around 2, and containing no mineral acids, should be used. Alternatively an alkaline cleaner with a pH of up to 11 may be used, provided its sodium or potassium hydroxide content is less than 0.01% when diluted. Both should be diluted with water as recommended by the chemical manufacturer. The cleaner should be liberally applied and quickly removed from the floor by squeegee and suction as recommended by the chemical manufacturer.
3. For heavy duty scrubbing of small areas, higher alkaline cleaners up to pH 13.5 may be used provided the sodium or potassium hydroxide content is less than 2% in the concentrate and is diluted to at least 100:1 with water. The solution should then be removed from the surface with copious quantities of water. This method should not be used daily as residual cleaner will attack the tile surface and cause the grout to blacken.
Before using these products (1, 2 & 3) get professional written advice from the chemical manufacturer as to the suitability, application and frequency of use of their product on fully vitrified porcelain tiles.