Safety Meets Sustainability

Rob Klein, MS, CIHEnvironmental Health & SafetyYale UniversityNew Haven, CT

Making Universities SustainableCopenhagen, Denmark23 October 2014

Partnerships at Yale• Sustainability• Facilities / Utilities / Systems Engineering • Purchasing and Procurement • Yale Animal Research Center• Lab Managers & Researchers• Environmental Health & Safety

Modern Laboratories• Protect research materials and people• Highly engineering for odor control, comfort, and safety• High flux of supplies, materials, and hazardous wastes• Trend towards disposal products• Primarily 100% exhaust air• Energy-intensive• All labs are not =

Lab Type Rooms

Biomedical 3,287 (70%)

Research Animal (husbandry, procedure, and support)

567 (12%)

Chemistry 251 (5%)

Engineering & Physics 242 (5%)

Environmental, Geology, and Planetary Sciences

182 (4%)

Teaching 48 (1%)

Pathology/Anatomy Services 1 28 (1%)

All Other 18 (<<)

Total 4,623 (100%)

1 Includes surgical path lab services, autopsy, and gross anatomy

Laboratory Footprint at Yale

Total gross space at Yale – owned and leased

19.3 M ft2

Assignable lab space(includes owned and leased)

1.3 M ft2 (6.3%)

Utilities consumed by labs US$ 32 M/year (= 50% of total)

!!!

HVAC 82%

Electrical Equipt10%

Lighting8%

Energy Consumption in Yale Labs (US$ 32 M/year)

Chilled water 41% Steam 31% Electricity 10%

US$ 2M/year regulated waste disposal

Vs.

Historical Tension Areas

• General lab room ventilation• Fume hood flow rates• Recycling chemical containers• Excess protective equipment use in animal research• Freezer and contents management

Obstacles to Change

• “We’ve always done it this way”• Requirements from regulatory agencies and

accrediting organizations• Over-designed systems• Changes in research – reagents, equipment • Indirect costs externalize involvement• Funding rules that limit “sharing” and encourage

over-buying (“use it or lose it”)

General Laboratory Ventilation• Background:

– Control emissions, reduce odors, and clear spills

• Tension: – 100% exhaust of conditioned lab air, historically at rates of

4-12 or more ACH; even higher in animal facilities

• Safety concerns:– Older epidemiological data suggest higher incidence of

disease among chemists and other lab workers– Air flows too low will result in exposures

0 2 4 6 8 100

20

40

60

80

100

Air changesCon

cen

trati

on

(%

)

C = C o e -n

… in a Perfectly Mixed Room

Small Spills

Benchtop Work (x 6) “fugitive emissions”

Original Supply Air Diffusers

New Radial Style Supply Air Diffusers

Spills – Duct MeasurementsOriginal 6 Supply Air Diffusers

0 10 20 30 40 50 60 70 80 90 1000

5000

10000

15000

20000

25000

300006 ACH

8 ACH

10 ACH

12 ACH

14 ACH

16 ACH

Time (minutes)

Spills – Duct MeasurementsOriginal But Only 3 Supply Air Diffusers

0 10 20 30 40 50 60 70 80 90 1000

5000

10000

15000

20000

25000

30000

6 ACH

8 ACH

10 ACH

Time (minutes)

Co

nce

ntr

atio

n (

pp

m)

Spills – Duct Measurements3 New Style Supply Air Diffusers

0 10 20 30 40 50 60 70 80 90 1000

10000

20000

30000

40000

50000

60000

6 ACH

8 ACH

10 ACH

Time (minutes)

Co

nce

ntr

atio

n (

pp

m)

Supply Air Diffuser Effects

Spills

(Duct Measurements)4 6 8 10 12 14 16 18

05000

1000015000200002500030000350004000045000

Peak Concentration

Original 6 grilles

Power (Original 6 grilles)

Original 3 grilles

ACH

Co

nc

en

tra

tio

n (

pp

m)

4 6 8 10 12 14 16 180

5

10

15

20

Speed of Peak

Original 6 grilles

Power (Original 6 grilles)

ACH

Pe

ak

Pu

lse

Tim

e (

min

)Observations:

• Higher [peak]’s

• Faster clearance

CFD Modeling - Residual Contamination (benchtop emission model, time = 70 min, 6 ACH)

6 original supply air diffusers

3 new supply air diffusers

Empirical Conclusions

• Higher ACH → lower concentrations, faster clearance• Greatest improvement from ~ 4 - 6 ACH• But diminishing returns ≥ 8 ACH • Reducing number and style of SA diffusers provides

functional equivalent of 2 – 4 additional ACH vs. original room HVAC design

• Must consider original HVAC system design before lowering ventilation rates

• Be aware of the limitations of demand control systems

Very Serious Cost Savings• @ US$ 8 / CFM exhaust / year (average):

– 1 ACH reduction ~ $1,400 / yr test lab alone– $116,000 / yr this bldg alone– $1.95 M / yr entire campus

• With proper room HVAC design, we now accept 6 ACH, less in unoccupied labs

Shameless self-promotion: 2 articles in J Chemical Health & Safety – Klein, King, and Kosior

Some Other Successes

Conclusions and Advice

• Data-driven• Dialogue, communication, and teamwork• Open mind and willingness to consider change

Questions?