Document nqYy8g96ZEXNMBq4YEnd7v46

114 BOSS A. MC FARLAND I t 4 4 10 *0 ......40-40 40100 VIBRATION FREQUENCY-CYCLES PER SECOND Figure 13. Subjective responses to vibratory motion. The chart is based on the averagediS values of various investigators and is valid for exposures up to a few minuteB. The vertical's arrows represent one standard deviation above and below the means. (From Goldman") HUMAN ENGINEERING AND INDUSTRIAL SAFETY 115 5'ijunplitude must be to maintain a given level of comfort, and vice versa. By referrm'g^io Figure 13 limits may be determined for any given amplitude or frefluSncy.100 Ideally, of coprse, both should be reduced as much as possible. * "Mm. * V. Summary and Conclusions he objective of this chapter is to indicate methods of controlling the human je|orkinvolved in industrial accidents through the application of human engineegllteprinciples to problems of equipment design. It is emphasized that closer cql^rai'ation should be developed and maintained between the medical and biojl.tjl,kv`jgsln ...........and the design and safety engineer. The latter can assist those '^bpiYcerliS with human variables by defining the practical problems that exist in while the former can furnish data in regard to human capabilities and 5jyi_mitations. The areas relating to human factors that have been found to have ftffiol|0aon8 for industrial safety are outlined. Emphasis is placed on the fact |||l|affety will be improved if mechanical design is more intimately related to ^^^Spmical, physiological, and psychological characteristics of the operators ^l||||l||i|Les. This implies that machines and working areas be designed from the HSwgBard. with the instruments and controls considered as extensions of his -System and body appendages. On the engineering side, an advance analysis ^ri'i,]ible faults in the equipment and working areas is necessary, for if de- gpresent, it is only a matter of time until some operator fails and has an E'hese'operHtionahanaiyses'may be'made with the aid of such techniques ||jV8 and questionnaires, time and motion studies, and.the study of errors fflicjfinear acoidents. * *Emcr the biologist has become familiar with the specific industrial problems |pK|ng situations he can furnish the anthropometric data necessary to insure Jteglearances, adequate accessibility to controls apd materials, and proper rat-; jpg$|Anthropometric data and methods of application are presented, which Fin this regard. HjSlration is next given to the design of displays and controls. Displays ithe various sense organs information regarding the functioning of the iifie equipment. Factors affecting visibility are discussed in relation to ^j^|l|d'etHil7-contrast;-illumination; time-of-expdsiirej-ahd color;-Experijlndings are reported in regard to optimum shape, size, ,and design of dials focafclrs. Many of these findings are applicable to the Resign of gauges, "Wqiflling apparatus, and so forth, and various other industrial mechanical p&r.efrequently.misread or misinterpreted. The use. of-auditory, tactual, ' Vtic displays that impart information to the workers is also discussed. IGoldman, A Review of subjective responses to vibratory motion of the human |fr|guency range 1 to 70 cycles per second, Project NM-004-001, Report 1, Natipnal HgResearch Institute, March, 1948. See also Ride and Vibration Data, Special (SP-6) Soc. Automotive Engrs., New York, 1950. '