A professional who repairs and adjusts mixing and packing machines used in production of nitroglycerin and dynamite. Respnsibilities include:

• Washes machines and parts with sodium carbonate or other neutralizing compound prior to and during dismantling to minimize danger of explosion, using brush and rags.
• Determines cause of equipment malfunction, according to knowledge of machine operation and report of operator or maintenance workers.
• Dismantles, repairs, and replaces machine parts, using nonsparking handtools.
• Observes safety regulations while working in explosive areas.