Acetic anhydride, a vital chemical for acetylation reactions, is used extensively to manufacture everyday products like aspirin and photographic film. In fact, over one million tons is produced annually in the United States alone. The carbonylation of methyl acetate facilitated by iodide species is a common method for its production. However, an intermediate chemical in this process, methyl iodide, can pose severe health risks and even act as an acute neurotoxin in high enough doses. Monitoring methyl iodide levels around production plants is often crucial for personnel safety. Applied Analytics’ OMA-300 ultraviolet spectrometer offers an effective solution by leveraging methyl iodide's absorption at 260nm. Moreover, the flexibility provided by the OMA-300 allows for the use of extended-length flow cells. These extra-long flow cells enable precise monitoring even at trace levels, to help ensure a safer work environment.