A solid background in chemistry and instrumental analysis, as well as a solid understanding of criminalistics, is required. For employment in crime laboratories, an undergraduate degree in forensic science or a natural science is necessary, as well as courses in math, biology, and chemistry. A Ph.D. is typically necessary for forensic research roles at university institutions, but it is often desired for progression to positions such as lab director. Arsonists, for example, frequently employ accelerants like gasoline or kerosene to accelerate burning and spread flames throughout a structure. A forensic chemist can take samples of both burned and unburned materials, extract the volatile hydrocarbons, and separate the components for gas chromatography examination.