Q: How can I clean mildew off of shower tiles without ruining the grout?

One of the biggest mistakes cleaning staff make when cleaning shower tiles and grout is using too caustic an acid or acid cleaner, which eventually eats away at the grout. The only acid recommended for this type of work is phosphoric acid. Hyrocloric and muriatic acid are too strong for surfaces and are dangerous for workers.

A proper cleaning program for shower tiles should include frequent use of a neutral disinfectant to remove body oils and other soil. Then, depending on the area and its amount of traffic, periodic deep cleaning with a phosphoric acid-based cleaner will break down mineral deposits where mold and mildew tend to reside. But even daily use of phosphoric acids can wear down grout and tile surfaces, so it should be used “as needed.”

Methods to apply acid cleaners include foam guns, which take more dwell time, sprays or the ‘old-fashioned’ apply and scrub method.
Mold and mildew need certain conditions to grow, including moisture, warmth and enough food (body oils and other soil). So regular cleaning to remove food will reduce outbreaks. Also, bleach may make a moldy area look better, but that only takes the surface mold off, leaving the base to grow again once conditions are right.

Tips compiled from Joel Mitchell of Saniglaze International Franchise and Eric Meadows, Hillyard chemical technical service representative.



Q: How do I calculate incident rates so I can compare them with national statistics?

To compute an incidence rate of occupational injuries and illnesses, first calculate the number of your department’s nonfatal injuries and illnesses. Then calculate the number of hours all of your staff actually worked. Use payroll or other time records to gather this information. "Hours worked” should not include any paid non-work time, such as vacation, sick leave, or holidays.

Multiply the number of injuries and illnesses by 200,000. Divide that number by the employee hours worked. This will equal the incident rate. (The 200,000 hours in the formula represents the equivalent of 100 employees working 40 hours per week, 50 weeks per year, and provides the standard base for incidence rates.)

Formula: (Number of injuries and illnesses X 200,000) / Employee hours worked = Incidence rate

The same number can be used to calculate incident rates for: Lost workday injury and illness cases, lost workday injury-only cases, lost workday illness-only cases, injury and illness cases without lost workdays, injury-only cases without lost workdays and illness-only cases without lost workdays. (NOTE: When comparing illness rates by types of illness, use 20,000,000 hours instead of 200,000 hours to get a rate per 10,000 full-time staff. You use 10,000 employees rather than 100 because illnesses occur less often than injuries, and in order to get a whole number as an answer you must use 10,000 employees.)

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