Rest Allowances - Fundamentals and Assessment Tools for Occupational Ergonomics - page 757

TABLE 38.10 Noise and Vibration Allowances
Points Noise

0 Working in a quiet office, no distracting noise; light assembly work

1 Work in a city office with continual traffic noise outside

2 Light machine shop; office or assembly shop where noise is a

distraction

4 Woodworking machine shop

5 Operating steam hammer in forge

9 Riveting in a shipyard

10 Road drilling

Vibration

1 Shoveling light materials

2 Power sewing machine; power press or guillotine if operator is

holding the material; cross-cut sawing

4 Shoveling ballast; portable power drill operated by one hand

6 Pickaxing

8 Power drill (two hands)

15 Road drill on concrete

Note: For noise, ILO (1992) considers whether the noise affects communication, is a steady
hum or a background noise, is regular or occurs unexpectedly, and is irritating or soothing. For
vibration, consider the impact of vibration on the body, limbs, or hands and the addition to
mental effort as a result, or to a series of jars and shocks.
Source: International Labor Office. 1992. Introduction to Work Study, 4th ed. Geneva, Swit-
zerland: ILO. With permission.

38.7.1 Cardiovascular System
The cardiovascular system is fatigued during “heavy” work — typically manual handling. A key question
is the duration of the work. Mital (1984a, b) reported that male material handlers could sustain, without
overexertion, for 8-h workdays, 29% of their maximal oxygen uptake; for 12 h shifts, the value declined to
23%. Moreover, Mital et al. (1994) found workers in an aircargo firm's package-handing area, working 2-
h shifts, worked at 40 to 54% of their treadmill aerobic capacity.

38.7.2 Musculoskeletal System
This section is divided into static work, dynamic work, and VDT work.

TABLE 38.11 Eye Strain Allowances

Points Degree

0 Normal factory work

2 Inspection of easily visible faults; sorting distinctively

colored articles by color; factory work in poor lighting

4 Intermittent inspection for detailed faults; grading apples

8 Reading a newspaper in a bus

10 Continuous visual inspection (cloth from a loom)

14 Engraving using an eyeglass

Notes: ILO (1992) considers the lighting conditions, glare, flicker, illumina-
tion, color, and closeness of work and for how long the strain is endured.
Source: International Labor Office. 1992. Introduction to Work Study, 4th ed.
Geneva, Switzerland: ILO. With permission.