New Law for Booster Seats Confusing if Your Child is 8

I read the article in the Spokesman carefully about the new booster seat law, but I am still as unclear as to what we are supposed to do as before. My son is eight years old and 4 feet 9 inches exactly. One part of the article seems to indicate that if a child has both of these descriptors he/she does not need to be in a booster. But another part of the article seems to indicate he needs a booster until he is nine years old. There must be other families out there with the same question—does he need to be in a booster or not? Help!