Chest X-ray is one of the most common examinations in pediatric radiography. Advanced skills are needed to obtain high quality images with minimum exposure. This Pediatric Chest Phantom is designed to find out optimal parameter and protocols to minimize radiation exposure to children. The phantom has two kinds of interchangeble lung inserts. The lung vascular insert can be used to study image quality in relation to CT / X-ray protocols images quality. The lung density insert allows users to evaluate dosage distribution in the lung field.