An activity relationship chart (ARC) is a tabular means of displaying the closeness rating among all pairs of activities or departments.[ 1] In an ARC there are six closeness ratings which may be assigned to each pair of departments, as well as nine reasons for those ratings (each is assigned by a reason code).
Rating symbols
A: Absolutely necessary
E: Especially important
I: Important and core
O: Ordinary
U: Unimportant
X: Prohibited or Undesirable [ 2]
Reason codes
Same table
Flow of material
Service
Convenience
Inventory control
Communication
Same personnel
Cleanliness
Flow of parts[ 2]
A rule of thumb is used to restrict the choice of rating letters:
Very few A and X relationships (no more than five percent) should be assigned
No more than 10 percent should be E
No more than 15 percent should be I
No more than 20 percent should be O
About 50 percent of the relationships should be U
Developing an ARC
List all the departments within the facility, and draw a rectangle around each one.
Draw a rhombus between each department, until you fully construct the rhombus as a tree.
Divide each rhombus into two halves; the upper half will contain the rating letter, while the lower half will contain the rating-reason code.
See also
References
^ Groover, M. P. (2007). Work Systems: The Methods, Measurement & Management of Work , Prentice Hall, ISBN 978-0-13-140650-6
^ a b Tompkins, J. A., White, J. A., Bozer, Y. A. (2010). Facilities Planning , Wiley, ISBN 978-0-470-44404-7