Comparison of Maximum Volitional Torque Exertion Capabilities of Males and Females Using Common Hand Tools

This study examines the effects of several operator- and task-related variables, defining the operator hand-tool system at the workplace, on peak volitional torque exertion capabilities of males and females with common nonpowered handtools. Maximum volitional torque was measured on 55 adult subjects (30 male, 25 female) in 540 treatment combinations (5 Tools x 2 Postures x 3 Heights x 3 Reach Distances x 6 Angles). Results of the study indicated that peak torque exertion capabilities of females average 66% of the male torques. Means for height and angle, although statistically different, had little practical difference. The major differences were in type of hand tool (30 kg-cm for screwdrivers versus 246 kg-cm for wrenches), posture (140 kg-cm for sitting versus 175kg-cm for standing), and reach distance (185 kg-cm at a distance of 33 cm versus 131 kg-cm at a distance of about 71 cm). Some of the task variable interactions were also significant. Among the various isometric strength and anthropometric variables, isometric shoulder strength was most important and appeared to limit the torque exertion capability of individuals. Peak torque profiles of males and females using common nonpowered handtools are presented.

[1]  E R Tichauer,et al.  Ergonomic principles basic to hand tool design. , 1977, American Industrial Hygiene Association journal.

[2]  P. Åstrand,et al.  Textbook of Work Physiology , 1970 .

[3]  P Andlauer,et al.  Oral temperature, circadian rhythm amplitude, ageing and tolerance to shift-work. , 1980, Ergonomics.

[4]  D. Chaffin,et al.  A proposed standard procedure for static muscle strength testing. , 1974, American Industrial Hygiene Association journal.

[5]  D. L Corrigan,et al.  Axe use efficiency A work theory explanation of an historical trend , 1981 .

[6]  D B Chaffin,et al.  Ergonomics guide for the assessment of human static strength. , 1975, American Industrial Hygiene Association journal.

[7]  James V. Bradley.  Glove Characteristics Influencing Control Manipulability , 1969 .

[8]  D O'Neill,et al.  Performance in gripping and turning -a study in hand/handle effectiveness. , 1975, Applied ergonomics.

[9]  John A. Roebuck,et al.  Engineering Anthropometry Methods , 1975 .

[10]  A. Mital,et al.  Maximum Frequencies Acceptable to Males for One-Handed Horizontal Lifting in the Sagittal Plane , 1983, Human factors.

[11]  M. M. Ayoub,et al.  Male-Female Differences in Variables Affecting Performance , 1978 .

[12]  A. D. Swain,et al.  Maximum Torque for Small Knobs Operated with and without Gloves , 1970 .

[13]  Anil Mital,et al.  Relationship between Lifting Capacity and Injury in Occupations Requiring Lifting , 1978 .

[14]  M. M. Ayoub,et al.  The determination of an optimum size cylindrical handle by use of electromyography. , 1971, Ergonomics.

[15]  James V. Bradley.  Effect of Gloves on Control Operation Time , 1969 .

[16]  C G Drury.  Handles for manual materials handling. , 1980, Applied ergonomics.

[17]  A Mital,et al.  Maximum Acceptable Weight of Lift as a Function of Material Density, Center of Gravity Location, Hand Preference, and Frequency , 1983, Human factors.

[18]  R DRILLIS,et al.  The Theory of Striking Tools , 1963, Human factors.

[19]  Vernard Foley,et al.  Dynamics of the Axe Swing , 1978 .

[20]  Colin G. Drury,et al.  Hand Placement in Manual Materials Handling , 1983 .

[21]  Michael W. Riley,et al.  An Evaluation of Handle Shapes and Sizes , 1982 .

[22]  R M White.  The Anthropometry of United States Army Men and Women: 1946–1977 , 1979, Human factors.

[23]  M. M. Ayoub,et al.  Modeling of Isometric Strength and Lifting Capacity , 1980 .

[24]  John G. Kreifeldt,et al.  Toward a Theory of Man-Tool System Design Applications to the Consumer Product Area , 1974 .

[25]  W. M. Keyserling,et al.  Preemployment strength testing: an updated position. , 1978, Journal of occupational medicine. : official publication of the Industrial Medical Association.