Field Olfactometry Odor Measurement

R.C. Brandt, PhD, PEDepartment of Agricultural and Biological EngineeringThe Pennsylvania State University

Penn State Odor Assessment LaboratoryUMES Odor Assessment Kick-off TrainingAugust 16 – 18, 2011University Park, PA

How are Odor Samples Secured for Laboratory Olfactometry?

Field Olfactometer

How is Odor Threshold ConcentrationMeasured in Ambient Air?

Is Field Olfactometry a New Idea?

Scentometer® • Research sponsored by the U.S. Public Health Service, 1958

• Originally manufactured by Barnebey-Cheney Corp, early 1960’s

• Now manufactured & sold by Barnebey and Sutcliff Corp.

Photo image by St. Croix Sensory, Inc.

Dilution of Odor in Ambient Air

Odor Source

Ambient Air Observer

Air Flow

D/T 2 7 304 15 60Dilution-to-Threshold using Field Olfactometry

Nuisance?

Original Scentometer D/T Interpretation

D/T Word Category2 Noticeable

7 Objectionable

15 Nuisance

31 Nauseating

How Are Odor Panelists Selected?

Smell Bell of Normal PopulationPe

rcen

tage

of P

opul

atio

n

8Anosmic Hypersensitive

<= =>

3 137654

5 % tile

9 10

5 % tile

11 12

Chart image by St. Croix Sensory, Inc.

Normal Population

Smell Bell

Pen-Test Sensitivity History

Odor Sensitivity Testing Results-Test Subject 560

2

4

6

8

10

12

14

16

a b a b a b a b a b

1 2 3 4 5

5/14/06 5/15/06 5/25/06 5/31/06 7/9/06

Odor Sensitivity Test Event

Pen

Test

Res

ult

Mean = 11.5 One Std. Deviation = 3.84 One Std. Error =1.21

Odor Sensitivity Testing Results-Test Subject 522

2

4

6

8

10

12

14

16

a b a b a b a b a b a b a b a b a b a b

1 2 3 4 5 6 7 8 9 10

7/14/05 8/12/05 8/22/05 11/2/05 5/15/06 5/17/06 5/24/06 6/5/06 6/21/06 7/14/06

Odor Sensitivity Test Event

Pen

Test

Res

ult

Mean = 9.85 One Std. Deviation = 3.03 One Std. Error =0.677

Why Field Olfactometry?Advantages: On-site “REAL-TIME” measurement No need for sample collection Lower detection levels possible Relatively low costDisadvantages: Does not provide emission rate Variable field conditions Personnel logistics

Multiple Assessor Repeat Observation Field Olfactometry Protocol

200 foot diameter manure ring

Prevailing WindDirection

Use of Manure Rings for Assessment of Dairy Odors from Alternative Application Methods

10 foot wide swath of manure (6000 gal/acre)

OdorPanel Advantages:

1.Eliminates wind direction as a primary source of variance

2.Maintains constant odor assessor distance from odor source

Surface Aeration Infiltration

Surface + Chisel

Shallow

Disk

DGI Control0

2

4

6

8

10

12

14

16

18

20

a

b

c d de

Pre-application <1.0 hr 2 to 4 hrs 24 hrs

Land Application Method

Fiel

d O

lfact

omet

ry D

/T (B

ET10

)

Shallow Disk

Direct Ground In-

jection

Field Olfactometry D/T versus Time

0 hn = 96

1 hn = 95

2-4 hn = 95

24 hn = 96

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

C

A

BB

Field NRO Observation Time Following Manure Application

Ave

rage

NR

O D

/T (

Log

BET1

0) Error bars represent one standard error.

Data with same character are not significantly different (a=0.05)

Use of Inventory Management to Mitigate Odor Emissions From Land-Applied Biosolids

0

5

10

15

20

25

3-Day 10-Day 50-Day No Biosolids

Fiel

d O

lfact

omet

er B

ET10

Treatment/ Biosolids Age

Hannum Farm Odor Study - Field Olfactometer Best Estimate Odor Threshold

Pre-Application <1 hr 4 hrs 10 hrs Next Morning

BB

A

C

Same letter indicates no statistical difference ..... composited over time (α=0.05).

y = 12.20x + 2.07R² = 0.75

0

5

10

15

20

25

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4Supr

a-T

hesh

old

Inte

nsity

(100

-pt.

scal

e)

LogBET10

Supra-Threshold Odor Intensity vs LogBET10

r=0.87

Sensory Comparisons -Odor Intensity versus Log BET10

y = -2.23x + 0.31R² = 0.79

-4.0

-3.0

-2.0

-1.0

0.0

1.0

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4

Hed

onic

Ton

e (2

2-p

t. sc

ale) LogBET10

Hedonic Tone vs LogBET10

r=0.89

Sensory Comparisons -Hedonic Tone versus Log BET10

y = -5.26x + 3.90R² = 0.85

0

5

10

15

20

25

-3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0Supr

a-T

hrsh

old

Inte

nsity

(100

-pt.

scal

e)

Hedonic Tone (22-pt. scale)

Intensity vs Hedonic Tone

r=0.92

Sensory Comparisons -Intensity versus Hedonic Tone

Use of Field Olfactometry for Quantification of WWTP Dewatering Facility Odors

1 2 3 4 5

6

78

9A 9B

10

1112

Penrose Avenue

Interstate - 95

0

10

20

30

40

50

60

70

#1 #2 #3 #4 #5 #6 #7 #8 #9A #9B #10 #11 #12

Fiel

d O

lfact

omet

er D

/T (B

ET 10)

Observation Station

7/14/2008

7/15/2008

7/21/2008

7/22/2008

7 BET10

Field Olfactometry D/T (BET10)

Sensory ComparisonsOdor Intensity versus Log BET10

1

23

4

5

6

7

89A

9B

10

11

12

y = 16.05x + 0.79R² = 0.98

0

5

10

15

20

25

30

35

0.0 0.5 1.0 1.5 2.0

Odo

r Int

ensi

ty (1

00-pt

Sca

le)

Log BET10

Odor Intensity versus Log BET10

Data point station IDs shown

r=0.99

1

23

4

5

6

7

89A

9B

10

11

12

y = -2.56x + 0.12R² = 0.98

-5

-4

-3

-2

-1

00.0 0.5 1.0 1.5 2.0

Hedo

nic

Tone

(22-p

t Sc

ale)

Log BET10

Odor Hedonic Tone versus Log BET10

Data point station IDs shown

r=0.99

Sensory ComparisonsHedonic Tone versus Log BET10

Swine Manure Odor Ring Study Log BET10 and % odor Reduction

NR PERC Field Maps 7-23-06.ppt 27

W

Layer House

ME

B

Poultry House Odor Mitigation using Shelterbelt vegetation

Fans

Air Sample Locations

West Middle East Background0.0

0.2

0.4

0.6

0.8

1.0

1.2

Without TreesWith Trees

Observation Location

Fiel

d O

lfact

omet

er D

/T (

LogB

ET10

) Bars represent one standard error.

Field olfactometry results suggest shelterbelt vegetation may assist odor mitigation.

Field + Laboratory OlfactometryUSDA-NRCS CIG Grant: Promoting adoption of innovative conservation cropping systems on livestock farms.

Field Olfactometry Indicates Shallow Disk Injection Reduces Dairy Manure Odors by 66%

Lab Olfactometry Indicates Shallow Disk Injection Reduces Dairy Manure Odors by 58%

Questions?

Take-Home PointField olfactometry works!This technology can provide vital information for high-value decision-making