High Pressure Spray Foam 

Application 

Air Monitoring Data

Scott Ecoff

Bayer MaterialScience 

February 15, 2012
Airborne Concentrations in Work 

Area

• 10 studies (1981-2009), 240+task and shift 

samples

Data compiled by Spence Consulting, LLC 

October 2009 (CPI Conference)

MDI Conc. (ug/m3)

All samples 8-h TWA

Applicators 5 - 2100 10 - 460

Helpers 0.1 - 408 1 - 308

Exposure Guidelines 200 (ceiling)

OSHA PEL

51 

TLV®
Study of 5 Homes: Airborne MDI Concentrations 

with Distance from Applicator

0

10

20

30

40

50

60

70

80

90

1 2 3 4 5

Concentration (ug/m3)

Survey No.

10 feet 20 feet 30 feet

OEL 51 ug/m3

Bayer Material Science: Karlovich 2008
SPF Survey at 5 Homes: Summary of 

MDI Results

o Airborne MDI for applicators exceeds the 8-hour and short-term OEL. 

o Airborne MDI can exceed the TLV at distances up to 20 feet from the 

applicator.

o Airborne MDI generally displayed a decrease with distance from Applicator 

(2007 Lesage et.al. observed same finding in study of SPF application in 5 residential structures; 

at 6-12 meters average MDI concentration of 11 samples were < OSHA PEL of 200 ug/m3; average 

airborne concentration in Applicator work zone was approximately 1,000 ug/m3).

o During Application, migration of MDI to lower floors was observed in some 

surveys, however, the airborne concentrations were not in excess of the 

OELs on those floors where identified (high values: 2.3 and 5.8 ug/m3; 

range was ND < 1 ug/m3 up to 5.8 ug/m3 based on 10 samples).

Bayer MaterialScience: Karlovich 2008 TLV = 51 ug/m3 (8-hr TWA); OSHA PEL = 200 ug/m3 (C)
Additional MDI Data from Recent 

Studies (2010 and 2011)

• Exterior Wall SPF Project: Commercial Structure

• Applicator: 4 personal samples 88-265 ug/m3

• Helper: 4 personal samples 37-65 ug/m3

• Area: 2 samples 25 ft downwind from applicator: 5 and 6 ug/m3

• Exterior Wall SPF Project: Commercial Structure

• Applicator: 4 personal samples 20-35 ug/m3

• Area: 25 ft downwind: ND < 0.8 , 6 ug/m3; 50 ft downwind: ND < 0.8, 1 ug/m3 

• Area: 25 ft behind applicator: 1 ug/m3 and 1 ug/m3

• Interior SPF Project: Residential Attic (fan used to create neg press)

• Applicator: 2 STEL samples: 1,110 and 1,150 ug/m3

• Area (floor below attic): ND < 1.5 and 3 ug/m3 during application

• Post Spray (inside attic/floor below): 12 hours: ND < 1.1 ug/m3

• Post Spray (inside attic/floor below): 24 hours: ND < 0.6 ug/m3

Bayer Material Science: Product Safety Studies TLV = 51 ug/m3 (8-hr TWA); OSHA PEL = 200 ug/m3
Variability of Airborne MDI During SPF 

Application 

• MDI Exposure Conclusions

• Both Applicator and Helper have potential for exposure 

above OELs; use of respiratory protection necessary

• Applicator levels 2-4 x Helper levels

• Both roles: highly variable results

• Indoor higher; Outdoor more variable but lower

• Factors causing variability:

• Natural ventilation

• Atmospheric and seasonal conditions

• Building characteristics (# of openings, size, air movement)

• Surface area and thickness of foam sprayed

• Applicator’s experience level 

Oct 2009/Spence
Exposure Control During Application –

Other Trades

• Administrative Controls to Protect Other Workers

• Work Practices

• Staying upwind of Applicator 

• “Work Zone” concept: defined area around point of 

spray

• Indoors: 6-8 m (20-25 ft) suggested

• Outdoors: 2-3 m (7-10 ft) suggested

October 2009/Spence
Post Spray Area Sample Data

• Summary of air and swipe testing after SPF application:

• MDI air monitoring data (four studies reviewed by Spence with post spray MDI testing):

• #1: high value was 19 mg/m3(this sample collected 15 minutes after application); all but 

one of fifteen post spray samples collected after 30 minutes post spray were ND < 1.2 

ug/m3; one detected at 3 ug/m3; all eight samples were ND that were collected 24 hours 

post spray 

• #2: 64 samples (collected 15-min to 2.5 hr post-spray): 62 samples were ND < 3 ug/m3, 

2 samples near 5.0 mg/m3; all ND for MDI oligomers 

• #3: 30 Samples Total @ 30, 60, 120 min: majority of samples were ND with range <0.01 to 

2.4 ug/m3

• #4: 2 samples 2 hr post-spray, MDI was ND; but MDI oligomers were detected at low levels

One Study (Lesage, et.al.) included monitoring for unreacted isocyanates on surfaces of 

newly installed SPF: 20 surface SWYPE samples collected.

Freshly applied foam tested positive for presence of isocyanates in all samples. 

Negative results were obtained for the same surfaces when re-tested 15 minutes after 

foam application. 

TLV = 51 ug/m3 (8-hr TWA); OSHA PEL = 20 ug/m3 (ceiling limit)
References 

REFERENCES FOR HIGH PRESSURE SPRAY FOAM PRESENTATION

1. Booth, K., B. Cummings, W. Karoly et al. 2009. “Measurements of Airborne 

Methylene Diphenyl Diisocyanate (MDI) Concentration in the U.S. Workplace,” J. 

Occup. Env. Hyg. 6: 228–238

2. Cowie HA, Hughson GW, Creely KS et al. 2005. An Occupational Hygiene Assessment 

of the Use and Control of Isocyanates in the UK. HSE Research Report 311. Sudbury, 

England: Health and Safety Executive, HSE Books, p. 64

3. Roberge B.; R. Gravel; D. Drolet. 2009. Diphenylmethane-4,4'-diisocyanate (MDI): 

Safety Practices and Concentration during Spraying of Polyurethane Foam. IRSST 

Report R-606. Montreal, Quebec, Canada.

4. American Conference of Governmental Industrial Hygienists (ACGIH® ). 1998. 

Documentation of the Threshold Limit Values and Biological Exposure Indices. 

Supplements to the 6th Edition. Cincinnati, Ohio: ACGIH. pp. 1581–1586.

5. Achutan, C., and R. Driscoll. 2005. NIOSH HEALTH HAZARD EVALUATION REPORT 

HETA #2004-0038-2966: US Roofing Contractors, Philadelphia, PA. NIOSH, 

Cincinnati, Ohio.

6. Streicher, R.P., C.M. Reh, R.J. Key-Schwartz, P.C. Schlecht, M.E. Cassinelli, and P.F. 

O’Connor. 2000. “Determination of Airborne Isocyanate Exposure: Considerations in 

Method Selection.” Am. Ind. Hyg. Assoc. J. 61:544–556.
References (con’t) 

7. Lesage, J., J. Stanley, W.J. Karoly, and F.W. Lichtenberg. 2007. “Airborne 

Methylene Diphenyl Diisocyanate (MDI) Concentrations Associated with the 

Application of Polyurethane Spray Foam in Residential Construction”, J. Occup. 

Environ. Hyg. 4:145–155.

8. ACGIH 2008. 2008 TLVs® and BEIs®: Threshold Limit Values for Chemical Substances 

and Physical Agents. Cincinnati, OH: American Conference of Governmental 

Industrial Hygienists.

9. CFR 2003. 29 CFR 1910.1000. Code of Federal Regulations. Washington, DC: U.S. 

Government Printing Office, Office of the Federal Register.

10. Karlovich, B. 2009. “Air Monitoring Investigation: SPF Installation in Residential 

Dwellings”, Bayer Material Science, Unpublished report.

11. Crespo, J., and J. Galan. 1999. “Exposure to MDI During the Process of Insulating 

Buildings with Sprayed Polyurethane Foam”, Ann. Occup. Hyg. 43:415–419.

12. Bilan, R.A., W.O. Haflidson, and D.J. McVittie. 1989. “Assessment of Isocyanate 

Exposure during the Spray Application of Polyurethane Foam”, Am. Ind. Hyg. Assoc. 

J. 50:303–306.

13. Middleton P; Lichtenberg FW; Cleet C. 2003. “Application of EPA Air Contamination 

Models to Occupational and Environmental Exposures: Assessment of MDI 

Concentrations Associated with Rooftop Spray Foam Applications” in Proceedings of 

the Polyurethanes Expo 2003 : API International Technical Conference and 

Exposition. Washington, DC: API, pp. 18-23.
References (con’t) 

14. Hosein HR, and S. Farkas. 1981. Risk Associated with the Spray Application of Polyurethane 

Foam, Am. Ind. Hyg. Assoc. J. 42:663-665.

15. Research and Development Department, Construction Safety Association of Ontario. 1987. 

Assessment of Isocyanate Exposure During the Spray Application of Polyurethane Foam, 27p. 

Available online at: 

http://www.cufca.ca/views/ASSESSMENT%20OF%20ISOCYANATE%20EXPOSURE%20DU

RING%20THE%20SPRAY%20APPLICATION%20OF%20POLYURETHEN%20FOAM.pdf

, accessed 10 Aug 2009.

16. Canadian Urethane Foam Contractors Association (CUFCA). 2005. Assessment of Isocyanate 

Exposure During Outdoor Spray Application of Polyurethane Foam for Cavity Wall 

Insulation. CUFCA Safety Bulletin, Winnepeg, Manitoba: Canadian Urethane Foam 

Contractors Association.

17. Center for the Polyurethanes Industry (CPI). 2002. Model Respiratory Protection Program for 

Compliance with the Occupational Safety and Health Administration’s Respiratory Protection 

Program Standard 29 C.F.R. §1910.134. CPI Technical Bulletin AX246. Available online at 

http://www.polyurethane.org/s_api/bin.asp?CID=885&DID=3990&DOC=FILE.PDF, 

accessed 20 Aug 2009.

18. Center for the Polyurethanes Industry (CPI). 2002. PMDI User Guidelines for Protective 

Clothing Selection. CPI Technical Bulletin AX178. Available online at 

http://www.polyurethane.org/s_api/bin.asp?CID=885&DID=3853&DOC=FILE.PDF, 

accessed 20 Aug 2009.

References used by Mark Spence for paper presented at CPI Conference in 2009.