Activity Relationship Analysis Chapter 6 Activity Relationship Analysis

Objectives After reading the chapter and reviewing the materials presented the students will be able to: Understand activity chart and its function. Identify relationship codes. Utilize the block diagram to analyze flow.

Introduction Activity relationship analysis will help the facilities planner to place each department, office, and service area in the proper location. The objective is to create the most efficient layout possible.

Activity Relationship Diagram The activity relationship diagram, also called affinity analysis diagram, shows the relationship of every department, office, or service area with every other department and area (fig 6-1, page 177). Closeness codes are used to reflect the importance of each relationship: A - Absolutely necessary that these two departments be next to each other. E - Especially important I – Important O – Ordinary importance U – Unimportant X – Closeness undesirable The A code should be restricted to the movement of massive amounts of material between departments for example steel receiving to the steel storeroom. It will be difficult to handle more than eight A codes. Use E code if there is any doubt that it is an A code. Use I and O codes where some level of importance is desired. U codes are useful because they tell you no activity or interface is needed between two departments. X codes are as important as A codes, but for opposite reason. Noise, smell, heat, dust, clod are good reasons for an X code.

Determining the Relationship Code The relationship or affinity code states the desired degree of closeness between two activity centers. A rule of thumb is that you should not exceed the following percentages for a given code: A – 5%, E – 10%, I – 15%, and O 25%. The total number of relationships, N between all possible pairs of work centers (n) can be determined by: N = n (n-1) / 2 For example with 25 different departments or work centers there will be N = 25 (25-1) / 2 = 300 relationship codes. The facilities designer should have no more than 15 A relationships (300 x 5% = 15).

Worksheet The worksheet can serve as an interim step between the activity relationship diagram and the dimensionless block diagram. Step-by-step procedure for the worksheet (fig 6-2, page 180): 1. List all the activities down the left hand side of a sheet of paper. 2. Make six columns to the right of the activity column and title them A,E,I,O,U, and X (relationship codes). 3. Taking one activity at a time, list the activity numbers under the proper relationship codes. Be sure each activity number appears on each line.

Dimensionless Block Diagram The dimensionless block diagram is the first layout attempt. It will be the basis for the master layout and plot plan. Step by step procedure (fig 6-3, page 181): 1. Cut up a sheet of paper into 2 x 2 inch squares. 2. Place an activity number in the center of each square. 3. Taking one square at a time, make a template for that activity by placing the relationship codes in the following positions: A relationship in the top left hand corner. E relationship in the top right hand corner. I relationship in the bottom left corner. O relationship in the bottom right corner. U relationships omitted. X relationship at the center under the activity number. 4. Each activity center is represented by one square. 5. Once the templates are ready, you place them in the arrangement that will satisfy as many codes as possible. All As should have a full side touching. All Es should have at least one corner touching. No X relationship should be touching (fig 6-4, page 182).

Flow Analysis Flow analysis is now performed on the dimensionless block diagram. Start with receiving and show the movement of materials to stores, to fabrication, to welding, to paint, to assembly and pack out, to the warehouse, and to shipping (fig 6-4, page 182). You would not want shipping or receiving to be located in the middle of the building. You would not want material to jump over one or more departments.

Computer Generated Activity Relationship Chart Software packages are available to aid facility planners in achieving solution to a layout problem. FactoryPLAN via a series of interactive menus and on-screen prompts assists the user in arranging a layout based on the closeness ratings between pairs of activity centers or work areas. The analysis is performed in 3 steps: 1. Create a data file containing activity center names. 2. Once the list is complete, the user is prompted to enter the affinity code and reason code between pairs of work centers. 3. The third step of the analysis is the generation of the activity relationship chart and the flow path diagrams. The software will generate an optimized layout based on the data that are entered by the user (fig 6-7, page 186).

Summary Activity relationship analysis will help the facilities planner to place each department, office, and service area in the proper location. The activity relationship diagram, also called affinity analysis diagram, shows the relationship of every department, office, or service area with every other department and area. The relationship or affinity code states the desired degree of closeness between two activity centers. The worksheet can serve as an interim step between the activity relationship diagram and the dimensionless block diagram. The dimensionless block diagram is the first layout attempt. Flow analysis is now performed on the dimensionless block diagram. Software packages are available to aid facility planners in achieving solution to a layout problem.

Home Work What does the activity relationship diagram show us? What are the 6 activity codes and for what do they stand? What does the relationship or affinity code state?