near acuity
Defined by the revised Handbook for Analyzing Jobs as clarity of vision at 20 inches or less. In Part A of “Selected Characteristics of Occupations Defined” in the revised Dictionary of Occupational Titles, the rating for the near acuity component appears fifth in the second set of physical demand ratings under the vertical heading “NA.”
neck
The neutral posture of the neck is straight. Awkward positions of the neck include bending the neck forward (beginning at neck flexion greater than 20 degrees) or backward (beginning at neck extension greater than 5 degrees) and to the side (lateral bending greater than 20 degrees), or turning (twisting) the head to the right or left (rotation greater than 20 degrees to the right or left).
NIOSH lifting equation
Defines a recommended weight limit for the lifting and lowering of objects.