Chaptre 2. Facility Layout Introduction Product layout Process layout Fixed position layout

1

Chaptre 2. Facility Layout1. Introduction2. Product layout3. Process layout4. Fixed position layout5. Facility layout supplement

2

IntroductionIntroduction

Facility layout design is necessary when building a new facility or Facility layout design is necessary when building a new facility or renovating an existing one in order to improve process flow and renovating an existing one in order to improve process flow and minimize waste space.minimize waste space.

Facility layout largely depends on the shape and size of the Facility layout largely depends on the shape and size of the building.building.

3

Facility layout is importantFacility layout is important

The overall layout of a facility will last for long time and only minor The overall layout of a facility will last for long time and only minor changes are possible after the building or renovation.changes are possible after the building or renovation.

Layout has enormous effect on daily operations.Layout has enormous effect on daily operations.

Layout dictate the distance a patient or staff member travelsLayout dictate the distance a patient or staff member travels

Layout influences the interations and communications of the staff Layout influences the interations and communications of the staff members.members.

4

Goals of Facility layoutGoals of Facility layout

Functionality:Functionality:

• Placing heavily interacted departments togetherPlacing heavily interacted departments together

• Placing apart departments that should not be closePlacing apart departments that should not be close

• Ensuring space and form requirementsEnsuring space and form requirements

• Facilitating communicationFacilitating communication

Cost savings:Cost savings:

• Reduction of travel timesReduction of travel times

• Reduce overall space requirementReduce overall space requirement

• Enabling for reduced staffing by placing similar job functions Enabling for reduced staffing by placing similar job functions togethertogether

5

Three basic types of Facility layoutThree basic types of Facility layout

Product LayoutProduct Layout

Process LayoutProcess Layout

Fixed position layoutFixed position layout

Can be used to either a single department or an entire facility.Can be used to either a single department or an entire facility.

But also:But also:

Retail store layoutRetail store layout

Warehousing and storage layout (relation of unloading and Warehousing and storage layout (relation of unloading and loading areas)loading areas)

6

Types of manufacturing systemsTypes of manufacturing systems

• Job-Shop productionJob-Shop production

• Process layout, functionally similar machines are groupedProcess layout, functionally similar machines are grouped

• Flow-shop productionFlow-shop production

•Product layout, machines are arranged along the Product layout, machines are arranged along the manufacturing processes of a productmanufacturing processes of a product

•Celluaire manufacturing systemsCelluaire manufacturing systems

•Hybrid layout, similar parts and corresponding machines are Hybrid layout, similar parts and corresponding machines are groupedgrouped

• Project shopProject shop

•Product is fixed, personnel and equipment brought to itProduct is fixed, personnel and equipment brought to it

• Continuous-flow processContinuous-flow process

•Chemical plants and flood industryChemical plants and flood industry

7

Organisation of hospitalsOrganisation of hospitals

• Mainly a functional organisation in care units and Mainly a functional organisation in care units and technique facility centers to which are associated all technique facility centers to which are associated all human/materail resources human/materail resources

• each patient travels from one unit to another each patient travels from one unit to another according to her clinical pathway defining the cares according to her clinical pathway defining the cares and tests neededand tests needed

• But also with pools of shared material/human But also with pools of shared material/human resources and human resources seconded to other resources and human resources seconded to other units, ...units, ...

8

Layout of an emergency departmentLayout of an emergency department

SurgerySurgery

RadiologyRadiology

E.R. triage roomE.R. triage room Emergency room admissionsEmergency room admissions

LaboratoriesLaboratories

E.R. bedsE.R. beds PharmacyPharmacy Billing/exitBilling/exit

Patient APatient A

Patient BPatient B

Patient A (broken leg) proceeds to ER triage, radiology, surgery, bed, Patient A (broken leg) proceeds to ER triage, radiology, surgery, bed, pharmacy, billing. Patient B (pacemaker problem): ER triage, surgery, pharmacy, billing. Patient B (pacemaker problem): ER triage, surgery, pharmacy, lab, bed, billing.pharmacy, lab, bed, billing.

9

Chaptre 2. Facility Layout1. Introduction2. Product layout3. Process layout4. Fixed position layout

10


The product layout arranges equipment (departments) in the The product layout arranges equipment (departments) in the order of production process flow.order of production process flow.

Generally used in mass production such as automobile assembly Generally used in mass production such as automobile assembly where the processes are standardized and there is little variation.where the processes are standardized and there is little variation.

Product layout is generally less flexible and requires higher initial Product layout is generally less flexible and requires higher initial equipment costs.equipment costs.

But it minimizes the process cycle time and increases equipment But it minimizes the process cycle time and increases equipment utilisation.utilisation.

Examples: hospital cafeteria, standardized biological tests.Examples: hospital cafeteria, standardized biological tests.

11


12


Product layout, known as assembly line balancing problem, is Product layout, known as assembly line balancing problem, is generally determined by the product or service itself.generally determined by the product or service itself.

Most decisions concern Most decisions concern

• assignment of basic operations to different workstations assignment of basic operations to different workstations

• in order to balance the workloads in order to balance the workloads

• such that each station has approximately the same cycle time, such that each station has approximately the same cycle time, i.e. the time for one item to pass through that workstation i.e. the time for one item to pass through that workstation (Why)(Why)

Two types of problems:Two types of problems:

• Using a minimum number of workstations to achieve a given Using a minimum number of workstations to achieve a given cycle timecycle time

• Minimizing the cycle time given the nb of workstationsMinimizing the cycle time given the nb of workstations

13


An example of 3 stations and cycle time 70.An example of 3 stations and cycle time 70.

Waste time = ?, workstation cycle time = ?Waste time = ?, workstation cycle time = ?

14

Product layoutProduct layout

• Since variability is inherent in health care, the product layout is Since variability is inherent in health care, the product layout is rarely used in health care other than for supporting activitiesrarely used in health care other than for supporting activities

• Although the health care process is similar for a patient group Although the health care process is similar for a patient group with similar diagnosis, the amount of time that patients spend in with similar diagnosis, the amount of time that patients spend in each process varies greatly. Line balancing is impossible.each process varies greatly. Line balancing is impossible.

15

Chaptre 2. Facility Layout1. Introduction2. Product layout3. Process layout4. Fixed position layout course materials on : http://www.emse.fr/~xie/GIH/

16

Process layoutProcess layout

The process layout, known as layout by functionality, groups The process layout, known as layout by functionality, groups different types of process (departments, equipments) together to different types of process (departments, equipments) together to provide the maximum flexibility.provide the maximum flexibility.

Hospital groups together functions such as intensive care, Hospital groups together functions such as intensive care, surgery, emergency medecine, and radiology as separate surgery, emergency medecine, and radiology as separate departmentsdepartments

The flexibility allows accomodate the variability of patient flows The flexibility allows accomodate the variability of patient flows and times while preserving high utilisation of resourcesand times while preserving high utilisation of resources

The downside of a process layout is the large travel time, and The downside of a process layout is the large travel time, and high material handling costs. A good layout will reduce this high material handling costs. A good layout will reduce this negative impact.negative impact.

17


18


19

Closeness-based methodCloseness-based method

Identify the desireness and undesireness of closeness by Identify the desireness and undesireness of closeness by closeness rating chartcloseness rating chart..

Codes for desired closeness:Codes for desired closeness:

A – absolute necessaryA – absolute necessary

E – very importantE – very important

I – importantI – important

O – ordinary importantO – ordinary important

U – unimportantU – unimportant

X – undesirable.X – undesirable.

20


Closeness rating chartingCloseness rating charting

A

E

AO

U

IE

X

I

E

U

I

U

X

X

1. Nurses’ station1. Nurses’ station

2. Ambulance entrance2. Ambulance entrance

3. Patient Room Area3. Patient Room Area

4. Laundry4. Laundry

5. Main entrance5. Main entrance

6. Dietary Department6. Dietary Department

40*8040*80

40*4040*40

remainingremaining

40*8040*80

80*8080*80

40*8040*80

area in marea in m DepartmentDepartment

21


Using a heuristic rule to design layout.Using a heuristic rule to design layout.

Step 1. Assign departments to available spaces according Step 1. Assign departments to available spaces according desired closeness relationships identified as absolutely necessary desired closeness relationships identified as absolutely necessary or undesirable, i.e. A and X, by starting with the most frequent or undesirable, i.e. A and X, by starting with the most frequent department in either relationship.department in either relationship.

A graph representation of A and X closeness can be built.A graph representation of A and X closeness can be built.

Step 2. Consider other departments with relationships E, I, O, U.Step 2. Consider other departments with relationships E, I, O, U.

22


Ambulance Ambulance entranceentrance

Nurses’Nurses’StationStation

PatientPatientroom arearoom area

Main entranceMain entrance

LaundryLaundry

DietaryDietaryDepartmentDepartment

AA AA

XX

XX

XX

A and X closeness representationA and X closeness representation

23


2 Ambulance 2 Ambulance entranceentrance

1 Nurses’1 Nurses’StationStation

3 Patient3 Patientroom arearoom area

5 Main entrance5 Main entrance

4 Laundry4 Laundry

6 Dietary6 DietaryDepartmentDepartment

AA AA

XX

XX

XX

A and X closeness representationA and X closeness representation

24


Final layoutFinal layout

5. main5. mainentranceentrance

Amb.Amb.entranceentrance

4. L

aun

dry

4. L

aun

dry

6. D

ieta

ry6

. Die

tary

De

pt.

De

pt.

1 nurses’1 nurses’stationstation

3. Patient Room area3. Patient Room area

400 m400 m

200 m200 m

25

Distance and cost-based methodDistance and cost-based method

This method tries to minimize the costs or repetitive distances This method tries to minimize the costs or repetitive distances traveled by patients and staff.traveled by patients and staff.

Data representing such traffic are represented in a Data representing such traffic are represented in a from-to chartfrom-to chart which represents the nb of trips or flows between departments.which represents the nb of trips or flows between departments.

Once the traffic information is identified, departments with most Once the traffic information is identified, departments with most frequent traffics are assigned to adjacent locations.frequent traffics are assigned to adjacent locations.

Informations such as department space requirement, fixed Informations such as department space requirement, fixed locations, ... can be taken into account.locations, ... can be taken into account.

The problem is highly combinatorial when the nb of department is The problem is highly combinatorial when the nb of department is large and software tools such as CRAFT are necessary.large and software tools such as CRAFT are necessary.

26

Distance measuresDistance measures

27


Formall, the objective is to Formall, the objective is to

Minimize total cost TC = Minimize total cost TC = ijij D Dijij W Wijij C Cijij

wherewhere

W =[WW =[Wijij] is the From-To traffic matrix] is the From-To traffic matrix

D =[DD =[Dijij] is the distance matrix (Manhattan distance or Euclidean ] is the distance matrix (Manhattan distance or Euclidean

distance, why)distance, why)

C =[CC =[Cijij] is the unit traffic cost] is the unit traffic cost

28

Distance and cost-based method Distance and cost-based method

Example:Example:

Consider a small hospital of 3 departments A, B, C. Three Consider a small hospital of 3 departments A, B, C. Three locations 1, 2, 3 of identical size are available.locations 1, 2, 3 of identical size are available.

Assume that a nurse can walk 100 feet in 30 seconds and earn Assume that a nurse can walk 100 feet in 30 seconds and earn $48 per hour.$48 per hour.

Unit traffic cost Cij = 0.004$ / foot walkUnit traffic cost Cij = 0.004$ / foot walk

locationlocation11

locationlocation22

locationlocation33

100 feet 100 feet100 feet 100 feet

29


Distance matrix (in feet)Distance matrix (in feet)

LocationLocation

From/ToFrom/To 11 22 33

11 -- 100100 200200

22 100100 -- 100100

33 200200 100100 --

Condensed traffic matrixCondensed traffic matrix

DepartmentDepartment

From/ToFrom/To AA BB CC

AA -- 33003300 14001400

BB -- 200200

CC --

Traffic matrix (in trips)Traffic matrix (in trips)


From/ToFrom/To AA BB CC

AA -- 10001000 300300

BB 23002300 -- 100100

CC 11001100 100100 --

30


locationconfiguration 1 2 3 TC

1 A B C 2520$2 A C B 3280$3 B A C 2040$4 B C A 3280$5 C A B 2040$6 C B A 2520$

Dept.Dept.BB

Dept.Dept.AA

Dept.Dept.CC

31

Distance and cost-based method : example 2Distance and cost-based method : example 2

The Walters Company’s management wants to arrange the 6 The Walters Company’s management wants to arrange the 6 departments of its hospital in a way that will minimise departments of its hospital in a way that will minimise interdepartmental material handling costs. They make an initial interdepartmental material handling costs. They make an initial assumption (to simplify the problem) that each department is 20x20 assumption (to simplify the problem) that each department is 20x20 feet and that the building is 60 feet long and 40 feet wide. The feet and that the building is 60 feet long and 40 feet wide. The process layout procedure that they follow involves 6 steps.process layout procedure that they follow involves 6 steps.

32


Step 1. Construct a « from-to-matrix » showing the flow of patients Step 1. Construct a « from-to-matrix » showing the flow of patients or personnals from department to department.or personnals from department to department.

50 100 0 0 20

30 50 10 0

20 0 100

50 0

0

33


Step 2. Determine the space requirements of each department.Step 2. Determine the space requirements of each department.


11


22


33


44


55


66

room1room1 room2room2 room3room3


Building dimensions and a possible department layoutBuilding dimensions and a possible department layout

34


Step 3. Develop an intial schematic diagram (qualitative Step 3. Develop an intial schematic diagram (qualitative RELation RELation DiagramDiagram) showing the sequence of departments through which ) showing the sequence of departments through which patients will have to move. Try to place departments of heavy flow patients will have to move. Try to place departments of heavy flow next to one antoher.next to one antoher.

11 22 33

4455

66

5050 3030

100100

2020

5050

1010 2020100100

5050

35


Step 4. Determine the cost of this layout with traffic cost of 1€ Step 4. Determine the cost of this layout with traffic cost of 1€ between adjacent departments and 2€ between non adjacent between adjacent departments and 2€ between non adjacent departments.departments.

Cost = 570 €.Cost = 570 €.

11 22 33

4455

66

5050 3030

100100

2020

5050

1010 2020100100

5050

36


Step 5. Try to improve this layout by trial and error to establish a Step 5. Try to improve this layout by trial and error to establish a reasonable good arrangement.reasonable good arrangement.

Switch departments 1-2 as there is a heavy traffic between dept. 1-Switch departments 1-2 as there is a heavy traffic between dept. 1-3. Cost = 480 €.3. Cost = 480 €.


22


11


33


44


55


66



37


Step 6. Prepare a detailed plan (Step 6. Prepare a detailed plan (Space Rel. DiagramSpace Rel. Diagram) considering ) considering space or size requirements of each department; that is, arrange the space or size requirements of each department; that is, arrange the departments to fit the shape of the building and obstables.departments to fit the shape of the building and obstables.

38

Quadratic Assignment Approach for identical dept. Quadratic Assignment Approach for identical dept.

ProblemProblem: Locate N : Locate N identical departmentsidentical departments on N locations in order to on N locations in order to minimize total traffic cost.minimize total traffic cost.

QAP model QAP model (Quadratic Assignment Approach)(Quadratic Assignment Approach)

Decision variable : Xij = 1 if dept. i is located at location jDecision variable : Xij = 1 if dept. i is located at location j

Minimize TC = Minimize TC = ijklijkl c cijkl ijkl XXik ik XXjljl

Subject toSubject to

jj X Xij ij = = ii X Xij ij =1=1

where where ccijklijkl = = ijijwwijijddklkl

ijij = unit moving cost, = unit moving cost, wwijij = inter-department flow, = inter-department flow,

ddklkl = inter-location distance = inter-location distance

39


40


41

Systematic Layout Planning (SLP)Systematic Layout Planning (SLP)

42


43


44


45


46


47


48


49


50


51

Chaptre 2. Facility Layout1. Introduction2. Product layout3. Process layout4. Fixed position layout

52

Fixed position layout Fixed position layout

The fixed-position layout consists of the fixed service positions The fixed-position layout consists of the fixed service positions where personnel and materials come together to perform the where personnel and materials come together to perform the service.service.

Generally used in industry when the product is either too large or Generally used in industry when the product is either too large or too delicate to more such as airplane assembly.too delicate to more such as airplane assembly.

In inpatient hospital rooms (especially in an intensive care unit), the In inpatient hospital rooms (especially in an intensive care unit), the service position is the patien bed.service position is the patien bed.

The operating table in an operating room is another example.The operating table in an operating room is another example.

53


Designing a fixed position layout entails positiioning several service Designing a fixed position layout entails positiioning several service positions withing a given area, each of which may require an positions withing a given area, each of which may require an adjacent but separate support area.adjacent but separate support area.

Conflicts about space constraints and timing have to be resolved Conflicts about space constraints and timing have to be resolved (suspended x-ray machine and overhead lighting)(suspended x-ray machine and overhead lighting)

54


55

Chaptre 2. Facility Layout1. Introduction2. Product layout3. Process layout4. Fixed position layout5. Facility layout supplement

56


Designing a fixed position layout entails positiioning several service Designing a fixed position layout entails positiioning several service positions withing a given area, each of which may require an positions withing a given area, each of which may require an adjacent but separate support area.adjacent but separate support area.

Conflicts about space constraints and timing have to be resolved Conflicts about space constraints and timing have to be resolved (suspended x-ray machine and overhead lighting)(suspended x-ray machine and overhead lighting)

Documents

Chaptre 2. Facility Layout Introduction Product layout Process layout Fixed position layout