Some parents may wonder why ride operators are so strict.
"Some of them, they get a little too stringent on. For instance, I know on one ride my son was maybe 1/16 of an inch off and they wouldn't let him on," said parent Joe Sanders.
Amusement park safety experts say height requirements are designed to weed out kids too small and too young to withstand the forces of the ride.
"If you fudge a quarter inch here, a half inch here, I mean where does it stop? The manufacturer says it's 48 inches, [then] it's 48 inches," said Al Scanlan, an Orange County Fair ride inspector.
Ben Pickett of RCS Carnival says all rides are different and have different motions.
"That's why we always encourage people to observe the ride before they ride or partake," said Pickett.
RCS Carnival provides the Orange County Fair rides. Equipment is tested and inspected daily. The company says most accidents happen when kids and adults don't follow rules or don't pay attention.
Make sure the ride's lap bar is securely fastened, particularly if your child is slim or tall for their age.
"If they're not locked down tight enough, then the computer won't let the ride start," said Scanlan.
Experts say if your child is too scared to get on a rollercoaster, it's never a good idea to force them.
"Maturity definitely plays a part and that's again why we want parents to make that determination whether that ride's best suited for their children," said Pickett.
Remember, risky behavior endangers everyone, and the goal is to have fun and stay safe.