Grumman/Butkus Associates Energy Efficiency Consultants and Sustainable Design Engineers

Commissioning Lessons Learned: Pressure-Critical Environments in HealthcareBy: John D. Villani, P.E., CCP, CEM, LEED AP Kurt S. Matsen, P.E., QCxP, LEED AP

This Presentation will cover…. Ø Healthcare Critical Environment Commissioning

o What is and Why do Commissioning (Cx)o Applicable Codes and Standards

§ USP 797/800§  IDPH/ASHRAE

o Cx Process § Design Phase

o Real world healthcare Cx examples that impact patient comfort and energy savings

o Cx Costs and Benefits

Commissioning Codes and StandardsØ  To conduct commissioning in the healthcare field, the

provider needs to be intimately familiar with the related codes and standardso  State Codeso  IBCo  IECCo  ASHRAEo  AIAo  ASHEo  CDCo  NFPAo  NEC

Operating RoomsØ Design ConsiderationsØ Occupied vs. UnoccupiedØ Healthcare Critical Environment Commissioning

o  What is and Why do Commissioning (Cx)o  Applicable Codes and Standards

§  USP 797/800§  IDPH/ASHRAE

o  Cx Process §  Design Phase

o  Real world healthcare Cx examples that impact patient comfort and energy savings

o  Cx Costs and Benefits

Case Study #1 – Hospital OR IssuesNew Surgical Pavilion Project Details•  56,000 Sq. Ft New Construction Space•  45,000 Sq. Ft. Renovation of Existing Hospital•  $35M Construction costs•  3 New Air Handling Units, ORs and Central Sterile•  15 New Operating Rooms (ORs)

Case Study #1 – Hospital OR IssuesAir Handling Unit Details• ORs served by two air handlers• 50,000 cfm each• Backup through cross over dampers• 50,000 cfm design during backup mode• 25,000 – 30,000 cfm during normal operation• Oversized design to handle backup mode• Coils design for smoke purge mode with is 100%

outside air

Case Study #1 – Hospital OR Issues1½ Year old surgical pavilion problems• Shut down due to increased infection rates• All ductwork was cleaned• Temperature and Humidity was found to be poorly

controlled and possible cause of infections• OR Temperature Range 60 – 78F• Relative Humidity Range 40 – 60 % RH• Occupied Mode – 30 Air Changes per Hour• Unoccupied Mode – 15 Air Changes per Hour

Everything looks good right?Supply CFM is in range, typically 18 to 23kDAT is just over the setpoint of 55Supply Static is at setpointBuilding pressure is at setpoint

SUPPLY SIDE OF AIR HANDLING UNIT

RETURN SIDE OF AIR HANDLING UNIT

Cx and RCx for Patient Comfort and Energy Savings 10

Case Study #1 – Hospital OR IssuesHumidification Issues•  Humidification control based on measured return air RH vs.

setpoint via reset schedule•  Frequent high humidity alarms

42%

44%

46%

48%

50%

52%

54%

56%

58%42% 44% 46% 48% 50% 52% 54% 56% 58%

Mea

sure

d R

etur

n A

ir H

umid

ity (%

)

Return Air Humidity Setpoint (%)

Humidifier Control Sequence Reset Schedule

Case Study #1 – Hospital OR IssuesØ ORs must be positive to all adjacent areas

Hospital Cx Examples – Case Study #1Ø Operating Conditions

o ORs were found going negatively pressurized during transition from occupied to unoccupied

o  30 ACH to 15 ACHo  Supply VAV box can decrease from occupied to

unoccupied CFM in approximately 60 seconds o Return damper controlled by room pressure sensor

takes 20 minutes to regain stable pressure control

Case Study #1 – Hospital OR Issues

Room Pressurization is controlled by actual pressure

Case Study #1 – Hospital OR Issues

3400 cfm

1700 cfm

Added a stepped control loop to go from occupied to unoccupied mode in 300 cfm increments every 5 minutes

Cx should help troubleshoot and offer results based suggestions

Hospital Cx Examples – Case Study #1Ø  Backup Mode

o  Backup unit tripped offline upon initiation of cross over modeo  Backup and restored unit BOTH tripped offline upon activation

and restart of failed unit§  Revised dampers and fan speed timing sequence of

operations§  USE Modulating instead of 2 Position valves / dampers.

These allow for control and manipulation of stroke time

Case Study #2 – OR New Construction

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OR cfm offset = 2,076 - 1,800 = 276 cfm ACTUAL (Design was ≈ 400 cfm) OR’s started with over 700 cfm offset due to no door sweeps or astragals and incomplete construction such as the med gas column

Due to high leakage rate, unoccupied cfm (ACH) needed to be much higher than design

Cx should help troubleshoot and offer results based suggestions

Code is +0.01” Typically maintain +0.02” to +0.04” OR is cfm offset controlled

ADDED

Compounding Pharmacy LabsØ Design Considerations

o USP 797/800o  Lab Equipment and Filtrationo Decontamination

Ø Construction ConsiderationsØ Case Studies (Functional Testing)

Compounding Pharmacy Labs

Non-Sterile HD Compounding C-SEC•  Physically separated•  Exhausted to outside•  12 ACH•  Negatively pressurized to adjacent

spaces, .01” to .03”

Sterile HD Compounding C-SEC•  ISO 7 Buffer from ISO 7 Ante•  Exhausted to outside•  30 ACH (supply air)•  Negatively pressurized, .01” to .03”

Compounding Pharmacy LabsØ  Lab Equipment and Filtration

o  Hire equipment consultant early§  Glove box vs BSC §  Benchtop working heights§  Ceiling access for balance dampers

o  Fan filter units§  Challenge ports§  Remote panel and/or pressure

gauges§  Accessible speed controllers and

disconnects§  In series with supply air?

–  Constant torque

§  Recirculation?–  Consider heat generation

Compounding Pharmacy Labs

Ø Decontaminationo  Paired fans for

continuous operationo  Manual bubble-tight

dampers at CA/CACI and BSC

o  Decontamination mode?o  Automatic bubble-tight

dampers on HD supply airflow

Compounding Pharmacy Labs

Ø Construction Considerationso  Tightness of room o  Pupy padso  Door sweepso  Sealing around all pass-through equipmento  Door closure adjustments

USP 797 Pharmacy Lab– Case Study #1Intended as USP 797 Compounding Lab:•  G/BA had over 30 Cx design comments•  Wrong hood type in non-Chemo Room•  Lack of coordination between disciplines•  Return air terminal boxes shown backwards•  Workroom and Gowning designed more stringent

than required•  Pressurization as shown was not correct•  Pressure monitors not shown in drawings•  Transfer duct shown in Gowning•  Fire dampers shown in HD exhaust•  No automation sequences or schematics were

provided•  Building, and Lab, was served by self-contained

RTU•  Return system was plenum except for few areas,

and drawings called for night setbacks!

USP 797 Pharmacy Lab– Case Study #1

USP 797 Pharmacy Lab– Case Study #1

Initially, all doors had sweeps and frame sealsCode, and therefore testing, requires that rooms must remain properly pressurized when any single door is openedProblems:•  Pass-through window in Workroom caused

Gowning to drop in pressure•  When opening up Chemo Compounding the

Gowning-Ante door would go neutral

USP 797 Pharmacy Lab– Case Study #1

After all that work, pressures are maintained while the space was being cleaned and prepped for occupancy!

USP 797 Pharmacy Lab– Case Study #2

USP 797 Pharmacy Lab– Case Study #2

The entire return air system had to be rebalanced in order to maintain minimum negative static for Pharmacy VAVs

Isolation RoomsØ Design ConsiderationsØ Construction ConsiderationsØ Case Studies (Functional Testing)

Isolation RoomsØ Design Considerations

o  IDPH/ASHRAE§  Airborne Infection Isolation (AII) Room – 12 ACH, Negative to adjacent§  AII Ante Room – 10 ACH, No pressure requirement to corridor

o  Diffuser layout in Ante Room§  Protective Environment (PE) vs AII

o  Room tightness§  Door sweeps?

Isolation RoomsØ Design Considerations

o  Isolation exhaust fan control§  Paired fans run together§  Isolation dampers to isolate fans§  Welded duct at discharge of EF when in

facility§  Static pressure reset?§  Direct pressure vs. Airflow offset control

BHPnew = (80%/100%)3 x BHPoldBHPnew = .512 x BHPold

Isolation Room – Case Study #1

Negative Containment Isolation Room with a single supply diffuser in the Anteroom.Client’s standard is to have the Anteroom positive to the corridor.

Isolation Room – Case Study #2

Negative Containment Isolation Room with a single exhaust grille in the AnteroomClient’s standard is to have the Anteroom negative to the corridor.

Isolation Room – Case Study #3

Negative Containment Isolation Rooms with a shared AnteroomClient’s standard is to have the Anteroom negative to the corridor.

Isolation Rooms Case Study #4

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No data on EF-2 is shown, VFD speed, static pressure or static pressure setpoint

ISO Rm 123.4 is in negative mode and not maintaining negative 0.01" w.c.

ISO Rm 123.3 is in negative mode and not maintaining negative 0.01" w.c.

Both ISO Rm's should be in alarm but neither indicate an alarm condition

Hospital Cx Examples– AFMS18” x 18” access door is ≈4’-5’ away from AFMS, is this accessible??

This AFMS is here

18”x18” AD

Cx Costs and Benefits

ASHE – Health Facility Commissioning Guidelines1.4 Negotiate the HFCxA Fee and Contract0.5% for large projects, 1.25% for small projects

Thank You - Questions

Ø  John Villani, P.E., LEED AP, QCxP, CEM, GBE jvillani@grummanbutkus.com

Grumman/Butkus AssociatesEnergy Efficiency Consultants and Sustainable Design Engineers