Arizona law requires all children under the age of five must be seated in a legally recognized child restraint system. In Arizona, children need to sit in some sort of child safety seat until they are at least 4 ft and 9 inches and reach the age of eight.Arizona law mandates that children under the age of eight and shorter than 4 feet 9 inches must be secured in an appropriate child restraint system. The state of Arizona requires that all children who are younger than eight years old and under 4'9" are properly secured in a child safety seat. Children 1 to 7 who weigh more than 20 pounds must be in a child restraint or booster seat. A child who is younger than 5 years old must ride in a child safety seat. Children should ride in a rear-facing seat until age 1 and a weight of 20 pounds. For children under a year old, Arizona law requires a rearfacing car seat that supports the entire body, including the head and neck areas. Even when a child is out of a booster seat, parents must still be careful when moving them to the front seat. The "Work on It" column in the June 2017 issue of.