Use a car seat with a harness for as long as possible, and keep it rear-facing for as long as possible (until your child reaches the manufacturer's height or weight limit). Keep your older child in a booster seat until at least 8 years of age and 57 inches tall. Have your child ride in a rear seat until age 13.
Flame atomic absorption spectroscopy instrument. Atomic absorption spectroscopy (AAS) is a spectroanalytical procedure for the quantitative determination of chemical elements using the absorption of optical radiation (light) by free atoms in the gaseous state.
AAS: associate of (or in) applied science degree; an associate's degree is generally a two-year degree (the term is used in the us; in canada, the term usually used for equivalent education is diploma).