A professional who tends equipment that evaporates ammonium nitrate solution to form crystals used in making dynamite. Respnsibilities include:

• Starts pump to move specified quantities of ammonium nitrate solution from storage tank to weighing tank.
• Opens valve to drain weighed solution into heated tub.
• Starts agitator to mix solution as water evaporates and turn material as it crystallizes.
• Weighs out and pours specified quantities of chemicals into tub to prevent hardening of ammonium nitrate and to ensure uniform crystallization, indicated by visual inspection.
• Opens gate in side of tub to transfer crystals to storage barrels.