Is Bleach Safe For My Shingles

According to ARMA (American Roofing Manufacturer's Association), the following is the recommended cleaning method.

"The most effective method of cleaning algae and moss from a roof is with a 50:50 mix of laundry strength liquid chlorine bleach and water. Apply with a sprayer and allow the solution to dwell on the roof surface for 15 to 20 minutes, and then rinse thoroughly with low pressure water"

ARMA Roof Cleaning Recommendation