Table 8 Operationalization of criterion variables

Manual

Work standing up (not in 91/2); Work sitting down; Carry heavy stocks; Working being exposed to smoke, dust, gases, vapors; Working being exposed to coldness, heat, wet, dampness, draft; Working with oil, dirtiness, mud (not in 79); Working crouched down, kneed, reclined, overarm; Working being exposed to strong tremor, crushes, vibrations (not in 91/2, 79); Working being exposed to dazzling light, or poor visibility / bad lightening (not in 91/2, 79; Working being exposed to hazardous substances, radiance (not in 79); Working being exposed to noisiness

Routine

Work is stipulated in the minutest details; One and the same work cycle / process is repeating in the minutest details; You are confronted with new problems that remain to be understood / familiarized with; Your tasks include process optimization or trying out new things;

Computer

Computer skills in application software;