Hazards and Prevention of Airborne Exposures and Risks - Dr. Renée Anthony, Great Plains Center for Agricultural Health, from the 2016 Iowa Pork Congress, January 27-28, Des Moines, IA, USA. More presentations at http://www.swinecast.com/2016-iowa-pork-congress

1. T. Renée Anthony, PhD, CIH, CSP
Department of Occupational and Environmental Health
The University of Iowa
renee-anthony@uiowa.edu
Pit Foam & Producer Safety:
Hazards and Prevention of Airborne
Exposures and Risks
Iowa Pork Congress
January 27, 2016 | 10:45 – 12:00
Hy-Vee Hall, Lower Level, Rooms 107 & 108

2. Seminar Objective
 Dr. Renée Anthony
 Identify chronic and acute health and safety hazards associated with
chemicals in swine production buildings
 Discuss identification and prevention alternatives
 Leon Sheets
 Share producer experiences of barn fire
 Dr. Dan Andersen
 Update state of knowledge of foaming manure
 Discuss prevention strategies

3. Objectives
 Provide Motivation and Rationale
 Identify chronic health hazards in swine production buildings
 Common contaminants
 Health risks: current state of knowledge
 Prevention options
 Discuss acutely hazardous gases: H2S and CH4
 Sources
 Risk factors
 Prevention considerations

4. Acknowledgements
 Great Plains Center for Agricultural Health
 CDC/NIOSH U54 OH007548
 Iowa Fatality Assessment and Control Evaluation (FACE)
 CDC/NIOSH 2U60OH008460-10
 Subcontract with the Iowa Department of Public Health (IDPH)

5. I: Chronic Health Hazards
 Air contaminants in swine CAFO
 Ammonia (NH3) – manure pits, urine
 Hydrogen sulfide (H2S) – manure pits
 Dust (respirable, inhalable) – food, animal dander, manure
 Endotoxin (on dust) – animal dander, manure
 Carbon monoxide (CO) – heaters
 Carbon dioxide (CO2) – heaters, swine respiration
 Workers in swine CAFO exhibit adverse health outcomes
 Declines in lung function (FEV1 dose-dependent)
 Increased prevalence of respiratory symptoms
(chronic cough, phlegm)
 Increased prevalence and amount of inflammation
(bronchial lavage)
 Clear need to reduce exposures to these workers

6. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest

7. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
O'Shaughnessy et al. (2010) A Task-specific assessment of swine worker exposure to airborne dust.
Journal of Occupational and Environmental Hygiene 7(1):7-13
Inhalable Dust Endotoxin

8. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
Duchaine et al. (2000) Influence of building maintenance, environmental factors, and seasons on airborne
contaminants of swine confinement buildings. AIHAJ 61(1):56-63
“Total” Dust Endotoxin Ammonia
Dust and ammonia significantly higher in winter.
(Endotoxins analyzed by different methods: not comparable between seasons)

9. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
Jacobson et al. (2005) Spatial, diurnal, and seasonal variations in temperature, ammonia, and hydrogen
sulfide concentrations in two tunnel ventilated sow gestation buildings in MN. Livestock Environment VII,
Proceeding of 7th International Symposium 18-20 May 2005, ASAE Publication 701P0205, 198-206
Hydrogen Sulfide (Gestation) Ammonia
(Breeding)
Significant increases in winter: 100 to 1000 ppb H2S, 2-25 ppm NH3

10. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
 Concentrations increase over the winter

11. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
 Concentrations increase over the winter

12. Risk Factors
 Clear need to reduce exposures to these workers
 Winter exposures are highest
 Concentrations increase over the winter
 Exposure recommendations:
 Single component – OSHA, ACGIH, other… not consider combined
effect to compounds associated with health outcomes
 Multiple component – Literature recommendations to prevent
declines in lung function and inflammation

13. Recommended Exposure Limits
Occupational Exposure Limits (OELs) ACGIH TLVs –
Single component limits, which do not account for mixtures
Threshold
Large Dust,
mg/m3
Small
(Respirable)
Dust, mg/m3 NH3, ppm CO, ppm
CO2,
ppm
OEL 10 3 25 25 5000
50% OEL 5 1.5 12.5 12.5 2500
10% OEL 1 0.3 2.5 2.5 500
Literature recommendations:
Donham et al. 1989,
1995
2.8 (T)
(<10% decrease
in FEV1)
0.23
7
(3% decline
in FEV1)
-
1540
(FEV50,
FEF50)
Vogelzang et al. 2000 2.6 (I) 7.2
Increased bronchial
hyperresponsiveness

14. Methods to Reduce Exposures
 Focus on dust/endotoxin exposure reduction
 Respiratory Protection: N95 Respirators
 Low Adoption: 26% of MN farmers “sometimes” used
(Odu et al. 2015)
 Iowa Outreach: Community college education
activities (fit testing, hands-on demonstrations) –
Sheridan, Rudolphi
 Engineering Controls
 Oil mist – Zhang et al. 1996; Senthilselvan et al. 1997;
Rule et al. 2005
 Recirculating ventilation with dust removal (winter) –
Park et al. 2013; Anthony et al. 2014, 2015; Peters et
al. 2015

15. Methods to Reduce Exposures
 Recirculating Ventilation Findings
 1000 cfm (5.4 air exchanges/hour)
 No increased room concentrations of gases from
operation (NH3, H2S, CO, CO2)
 Two air control units tested in farrowing barn
 Filtration (SDC) reduced particles by:
 33% for large (inhalable)
 41% for small (respirable)
 Cyclone reduced particles by:
 44% for large (inhalable)
 18% for small (respirable) Filtration (SDC) Cyclone

16. Methods to Reduce Exposures
 Recirculating Ventilation Findings
 Also identified high CO2 generated by
common LPG heaters
 Unvented heater (Yr 1)
Mean: 2480 ppm (330 ppm SD)
Exceeded 1540 ppm all days
Mean approached ½ single gas OELs
 Vented heater (Yr 2)
Mean: 1401 ppm (330 ppm SD)
Exceeded 1540 ppm on 5 of 19 days
 800 ppm drop due to heater
 Between years, outdoor temperatures
and sow/piglet counts also varied

17. Additional Information
 Detailed results of heater and ventilation studies available
 http://www.public-health.uiowa.edu/gpcah/center-
projects/intervention-to-reduce-exposures-in-cafos/
Ventilation Study:

18. II: Acute Effects - Manure Gases
 High concentrations for short periods of time result in serious
health and safety hazards
 Hydrogen Sulfide (H2S) – In manure pit
 50 – 100 ppm: altered breathing
 100-300 ppm: pulmonary edema
 500-700 ppm: collapse in 5 min, death 30-60 min
 1000 ppm: nearly instant death
 “Heavier than air”
 Methane (CH4) – In foaming manure
 Simple asphyxiant: every 4% increase in methane, 1% decrease
of oxygen
 Flammable at 5 to 15% (50,000 to 150,000 ppm)
 Foam: 50-70% Methane (too high to be flammable)
 When foam breaks: concentration dilutes and becomes explosive
 “Lighter than air”
Fact Sheets:

19. H2S Fatalities (2015)
“Quick” attempt to retrieve equipment from
pit resulted in two father-son fatalities in
summer 2015
Iowa FACE report 2005 IA 024/025

20. Preventing Manure Gas Fatalities
 Educate/warn: post signs
 Prevent accidental entries
 Don’t enter during / just after agitation
 Ventilate spaces prior to entry
 Enter only with adequate equipment
 Retrieval system (harness, mechanical lift)
 Standby-by person
 SCBA

21. Foaming Manure
 Methane (CH4) is trapped in the foam but is
released when foam breaks
 Sources of breaking foam:
 Dropped feed
 Manure agitation
 Pressure washing
 Methane dilutes to flammable concentrations
 Sources of combustion:
 Electric motors (e.g., pressure washers, feed systems)
 Pilot lights
 Welding/cutting
 Faulty/damaged wiring
 Smoking
 Critical to eliminate combustion sources during activities when
foam might break

22. Preventing Manure Gas Fatalities:
Monitors
 At-Risk decisions
 “I don’t have an SCBA, but I only need to go in for a second.”
 “I can hold my breath”
 “I have had the fan on long enough…”
 “I pumped days ago…”
 How can we tell if hazardous gases are at dangerous
concentrations?
 Monitors can provide risk information to producer in real time
 Prices are extremely low (single gas H2S ~$100)
 These units are commonly used in other industries
in high-hazard environments

23. Preventing Manure Gas Fatalities:
How to Select Monitors
Currently:
• No information on how long these
last when stored in AG
environments
• Selections based on purchase
cost and warranty
• Store in clean environment
• No “industry recommendations” for
calibration and sensor (“bump”)
check
• Bump check before every use
• Calibrate at least monthly and
immediately before planned
entries

24. Preventing Manure Gas Fatalities:
Operating Monitors
Prepare to Sample Air for Manure Gases
• Ventilate space
• Allow sufficient warm-up time
• Understand how long it takes your sensor to respond
– May take up to 90 seconds
• Obtain tools to measure at a distance:
– 4 feet in front of you in the direction of travel
– Mount monitor securely on stick or use probe with extension hose
• Confirm monitor is working:
– Bump-test with gas to make sure it alarms
– Calibrate per manufacturer’s instructions
• Identify alarm settings:
– Be clear what you need to do if monitors alarm

25. Preventing Manure Gas Fatalities:
Operating Monitors
Testing Order and Key Decisions:
1. Oxygen
%LEL won’t give reliable
numbers if insufficient O2
Need 21% O2
If lower, may have high
methane:
Get out!
2. %LEL
(flammable methane)
Need <1% LEL
10% LEL or more:
Get out!
3. H2S
>10 ppm: Chronic
health effects
100 ppm:
Get out!
The LEL of methane = 5% = 50,000 ppm
A reading of “1%LEL”  500 ppm methane

26. Preventing Manure Gas Fatalities:
Operating Monitors
To Test Prior to Entering Manure Pit
Test manure pit while
outside of it first
Do not enter!
Ventilate space then retest from outside
Safe
?
Test at entry location and every 4 feet
(in front, to side, above, below)
No
Yes
Notes:
• Monitors take time to get true concentrations (60 -90 sec).
• We set alarms lower than what can cause death.
• Concentrations can go up quickly, so react to low concentrations as
indication of inadequate ventilation.

27. Preventing Manure Gas Fatalities:
Operating Monitors
To Test for Methane Gas in Barn
Washing Barn
1. Prohibit entry
2. Prepare ventilation equipment and monitor
3. Implement shut-down for electricity and gas
4. Put monitor on worker during activity:
EVACUATE if %LEL Changes from 0%
5. If evacuate
– Continue ventilating room
– Return with a monitor, testing in 4 foot
increments, including ceiling level;
back out if concentrations still high
– Return to task only when %LEL = 0
6. When work is completed/foam not at risk of
breaking, continue ventilating until confirm no
methane
Hot Work
Changes to
feed system
1. Prohibit hot work
in barn with
foaming manure
2. If work must be
done, prevent
activities breaking
foam
3. Follow all
procedures to the
left
Pumping
Manure Pit
1. Prohibit agitation when less
than 2 feet between foam and
slats
2. Ensure pit fans are operating
3. Follow all procedures to the left
4. If anyone enters barn, O2,
H2S and %LEL monitors
should be used
5. Continue ventilating barn after
pumping back to background:
21% O2,
<1 ppm H2S,
0% LEL

28. Summary
 Multiple compounds in the barn are associated with long-term
adverse health effects
 Respirators or improved ventilation, particularly during winter, can
reduce health risks
 Acute hazards from manure gases still pose dangers
 Procedures via ASABE and Extension recommend ventilation duration
and safety protocols
 Available inexpensive technology can ensure concentrations
throughout the room are safe for activities
• Working with monitors to recommend maintenance and lifetime to
recommend specifics
• Developing training
 Booth 1210 contains specifics
 Sign-up sheet for those interested in
classes on using monitors

29. Questions?
Example monitors on display at Booth 1210
renee-anthony@uiowa.edu
www.gpcah.org
Fact Sheets: Ventilation Study:

30. QR code for gpcah web for farmers

31. Chronic Health Outcomes
Authors
Declines in Lung
Function
Increased Respiratory
Symptoms
Increased Airway
Inflammation
Zuskin (1992) –
Netherlands (N=59)
Cross-shift (FVC, FEV1,
FEF50, FEF25)
Lower pre-shift capacity vs
controls
Chronic cough, dyspnea, chest
tightness, chronic bronchitis (not
♂, N=41)
Cormier (1991) –
Quebec (N=102)
Obstruction (FEV1/FVC,
MMFR)
Choudat (1994) –
France (N=102)
Lower but insignificant
difference (MEF, FEF50,
FEF25)
Cough (morning, diurnal,
workplace), Work-related
sneezing
Pedersen (1996) –
Denmark (N=27)
Normal FEV1 More bronchial reactivity: (via
bronchoscopy and BAL --
increased lymphocytes,
neutrophils, increased
macrophage activity)
Larsson (1994) –
Sweden (N=14, non-
farmers)
BAL changes 1 day post
exposure

32. Chronic Health Outcomes
Authors
Declines in Lung
Function
Increased Respiratory
Symptoms
Increased Airway
Inflammation
Iverson (1990) –
Denmark (N=124
pig, 57 dairy)
No difference in dairy vs pig
farmer: FEV1 decrease 12
mL/year of farming
More wheezing, shortness of
breath, dry cough compared to
dairy farmer
Age, years in pig farming, and
smoking all associated with
bronchial hyperreactivity (PC20
histamine values)
Iversen (2000) –
Denmark (7-yr follow
up, N=135)
FEV1 declined more with pig
farmer: 53 mL/yr pig
(significant) vs 36 mL/yr dairy
(not significant)
No difference in FVC
Same as previous Small decrease in bronchial
hyperreactivity between pig and
dairy, only once correcting with
FEV1
Vogelzang (2000) –
Netherlands
(N=171)
Mean FEV1: 73 mL/yr,
FVC 55 mL/yr
n/a Increased bronchial
responsiveness (associated
with NH3, automated dry
feeding, wood shavings as
bedding)

33. Studies Relating Exposures to Outcomes
Contaminant Mean Conc. Recommendation To Prevent:
“Total” dust (A) 4.3 mg/m3
(P) 6.8 mg/m3
(A) 2.4 mg/m3
(P) 3.8 mg/m3 Chronic cough & phlegm
Respirable dust (A) 0.33 mg/m3
(P) 0.34 mg/m3
(A) 0.23 mg/m3
(P) 0.28 mg/m3
Chronic cough & phlegm; frequent
chest colds; febrile episodes
Endotoxin - total (A) 0.18 ug/m3
(P) 0.24 ug/m3
(A) 0.08 mg/m3
(P) 0.09 mg/m3  FEV1
Endotoxin -
respirable
(A) 0.17 ug/m3
(P) 0.23 ug/m3 n/a n/a
Ammonia 9 ppm 7 ppm FEV50, FEF50
Carbon dioxide 1740 ppm 1540 ppm FEV50, FEF50
Hydrogen sulfide n/d - -
Carbon monoxide n/d -
Donham et al., 1989 (Sweden, N=57)
(A) Indicates area sample, (P) indicates personal sample

34. Studies Relating Exposures to Outcomes
Contaminant Mean Conc. Recommendation To prevent:
“Total” dust 4.53 mg/m3 1.3* – 2.8 mg/m3 <10% decrease in FEV1
(>2 hr /day, 6 yr)
Respirable dust 0.23 mg/m3
- -
Endotoxin – “total” 202.35 EU/m3
- -
Endotoxin - respirable 16.59 EU/m3
- -
Ammonia 5.64 ppm 7.5 ppm 3% decline in FEV1
Carbon dioxide
Hydrogen sulfide
Carbon monoxide
Donham et al., 1995 (Iowa, N=201)
Not reported
*smokers had more response and effects not seen below 1.3 mg/m3

35. Studies Relating Exposures to Outcomes
Contaminant Mean Conc.
Recommended Exposure
Limit Association?
“Inhalable” dust 2.63 mg/m3 2.6 mg/m3
Yes
Entotoxin 105 ng/m3 - No
Ammonia 1.6 mg/m3 (2.13
ppm)
5.4 mg/m3
(7.2 ppm)
Limited
Vogelzang et al. 2000: Examined bronchial hyperresponsiveness