Starts machine that puts yarn under tension, passes skeins through caustic solution, and rinses skeins. Tests caustic solution, using hydrometer, and adds soda or water to maintain uniform strength as specified. Removes skeins from mercerizer and hangs skeins on rack of tank for neutralizing. Turns valves to start spray of water and neutralizing solution. Tests neutralization, using litmus paper. May weigh and mix caustic and neutralizing solutions according to formula. May extract moisture from yarn [EXTRACTOR OPERATOR (textile)] and dry yarn in steam chamber [SKEIN-YARN DRIER (textile)].
