## Thursday, April 19, 2012

### Effort Rating or Pace Rating in Stop Watch Time Study

Standard Pace

Presgrave thought the speed of motion of a man walking at 3 miles per hour on a level area or a man dealing a deck of cards into four equal piles in a half minute might be considered as representative of the normal speed. The speed of motions observed during these operations would be considered to be the standard for all operations. To make this representation more positive (and uniform), motion pictures would be made of an operator performing the specified operation. The film then becomes the constant yardstick from which reference can be made frequently or as desired.   Nadler commented that, this yardstick is like a meter definition. The yardstick defined by Presgrave is only like a measuring device. The yardstick itself was not standardized.

Nadler commented that within the limits of present knowledge, the concepts of this system up to this point represent the best practical answers.[1]

Presgrave [2] in chapter 13 discussed the appropriateness of taking  walking at three miles per hour speed as the standard for time study purposes. He also mentioned the standard of dealing a pack of card in 0.5 minutes.

Eskilson [3] came out with an equation that related the distance moved and the time taken with the acceleration.

D = (1/2)(a) (0.27T)2 + a(0.49T)(0.49T) + (1/2)(a) (0.27T)2

Barnes suggested that to demonstrate rating inside a company, some simple operations from the company or plant which can be performed by anyone should be selected. They must be standardized and the time for doing those jobs at normal pace has to be established ( 3 miles per hour walking is used as the standard yardstick). Then motion pictures are made of various operators and the tempo in percent of normal should be established. These films are to be shown to time study analysts as well as to others. By getting trained with these films even operators can do the rating apart from the time study analyst. (Page 300)