THE PRINCIPLES OF WORK STUDY 11 Method Study has also been used in the assistance of disabled persons, and one large company composed of disabled persons has used it extensively. It is safe to say that many severely handicapped men and women have been helped in creative effort by the use of Method Study specially applied. WoR•, MF. ASUREME•T We have all read the advertisement which states that a hotel is "five minutes from the sea". What does this mean ? At a walk, a run, by bicycle, by car ? The time taken to do work cannot be defined merely by time alone. Not only must the method and conditions be precisely defined, but the time selected for the work must either be derived statistically, which may be a lengthy process, or Work Measurement must be used. Work Measurement does this by laying down an arbitrary rating scale for speed and effort, the method and conditions being recorded in detail. Table 2 Arbitrary rating scale 30 Very slow 40 Slow $0 Rather slow 60 Normal 70 Rather fast 80 Fast 00 Very fast We do not normally rate lower than 30 or above 90. The one is too slow, the other too fast One of these ratings is applied to the time observed for the work. The time for the work is then calculated from the simple formula ß t r Normal time for the work = -- x -- 60 60 where t (seconds) is the time taken to do the work and r is the rating It will be seen that the rate at which the work is done is arithmetically related to a norm, i.e., a 60. For example, if work is done in 10 seconds at 70 r then the time for the work is 10 70 X -- = 0.194 normal minutes 60 60 This is the time which would be taken for the work by a person of normal physique working with normal speed and effort. No one can expect to work

12 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS without rest so to this we add an allowance for fatigue known as "Compensa- ting Relaxation"--10%. 0.194 Normal Minutes 0.019 Compensating Relaxation 0.213 Standard Work Minutes Such an assessment of work must be subjective, and it is necessary to enlarge what 60 is. For example: Walking by a person of normal physique in normal conditions on level ground (speed) .... 3 miles per hour Walking while pulling a garden roller (speed and effort) ............ 2 ...... Walking while pulling a garden roller following a snake border (speed and effort plus mental atten- tion) .............. 1 ...... 13 • T R COb 5TANT TIME SECS 12 II IO 8 5 30 40 50 60 70 80 9•O RATING Figure 8. Ideal Rating/Time curve