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Safer Choice

Spray Polyurethane Foam Product Types

View spray polyurethane foam (SPF) comparison chart.

SPF Type

  • Open-Cell (low density, half lb.)
  • Closed-Cell (medium density, 2 lb.)
  • Closed-Cell (high density, 3 lb.)

Uses

  • Larger insulation applications
  • Air sealant in hybrid insulation installation with fiberglass or other insulation material
  • Roofing applications (Closed-Cell, high density, 3 lb.)

Open-cell SPF two-component “professional” high-pressure system

Open-cell SPF two-component “professional” high-pressure system:
  • Low density
  • Expands aggressively
  • Dries soft
  • Lower R-value (~ 3.5 per inch)

*Photo Courtesy CertainTeed.

Applicator

  • Professional installer

Container size

  • 55 gallon drum containers

Engineering controls

Personal protective equipment (PPE)

Receive medical surveillance to ensure applicator is healthy enough to wear respirator. Ensure all equipment is intact upon use and ensure proper equipment maintenance. Vacate all unprotected workers and building occupants.

Chemical composition

  • SPF products contain approximately 50 percent Side A and 50 percent Side B. This chemical reaction generates heat. Side A contains very reactive chemicals known as isocyanates. Side B contains a polyol, which reacts with isocyanates to make polyurethane, and a mixture of other chemicals, including catalysts (which help the reaction to occur), flame retardants, blowing agents and surfactants.

Closed-Cell SPF Two-component “Professional” High Pressure SystemClosed-cell SPF two-component “professional” high pressure system:

  • High density
  • Expands less aggressively
  • Dries rigid
  • Higher R-value (~ 6.5 per inch)

*Photo Courtesy CertainTeed

Variations in chemical composition

  • Open-Cell Blowing Agents: Carbon Dioxide or Water

Application process

  • Sides A and B are pumped through heated hoses from supply tanks into a nozzle where the two components react and are spray applied at elevated temperatures (>150°F) and pressure (1200 psi). “Open” cell foam expands more vigorously than “closed” cell foam and should be applied in layers.
  • See photographs below illustrating expansion differences between open-cell and closed-cell SPF. Foam can expand up to 120 times its original volume. After the foam is applied, has expanded, and has cured, it may be trimmed or cut, as needed; this might especially be true for the use of “open” cell foam that may expand beyond the wall.

Chemical exposure potential

May be exposed to chemicals

  • During application
  • After application
  • During heat-generating processes such as drilling, welding, or sanding
  • During fires

Through

  • Aerosols
  • Vapors
  • Dust that may contain unreacted chemicals

Hazards

  • Asthma
  • Sensitization
  • Lung damage
  • Other respiratory and breathing problems
  • Skin and eye irritation

Re-entry

  • Some manufacturers recommend 24 hours after application for worker re-entry without the use of PPE and for re-occupancy by residents and other building occupants, but the recommended time may vary. Contact your manufacturer or supplier for specific guidance.

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View spray polyurethane foam (SPF) comparison chart.

Uses

  • Air sealant
  • Adhesive
  • Smaller insulation applications
  • Weatherization activities

Applicator

  • Professional installer
  • Weatherization worker
  • Available for do-it-yourself applicators, but the same precautions should be taken as with professional-use. DIY applicators are often unaware of inhalation and dermal hazards and may not have adequate knowledge, training and experience to wear adequate personal protective equipment.

Container size

  • Typically three to five gallons per container from the system house, but can be purchased in larger containers over the internet or in some retail markets

Engineering controls

Personal protective equipment (PPE)

Receive medical surveillance to ensure applicator is healthy enough to wear respirator. Ensure all equipment is intact upon use and ensure proper equipment maintenance. Vacate all unprotected workers and building occupants.

Read more information about personal protection when using two-component low pressure kits. Exit

Chemical composition

  • SPF products contain approximately 50 percent Side A and 50 percent Side B. This chemical reaction generates heat. Side A contains very reactive chemicals known as isocyanates. Side B contains a polyol, which reacts with isocyanates to make polyurethane, and a mixture of other chemicals, including catalysts (which help the reaction to occur), flame retardants, blowing agents and surfactants.

Variations in chemical composition

  • Closed-Cell Blowing Agents: HFC-245fa

Application process

  • Sides A and B combined at application site and sprayed on as a stream or bead. After the foam is applied, has expanded, and has cured, it may then be trimmed or cut, if needed.

Chemical exposure potential

May be exposed to chemicals

  • During application
  • After application
  • During heat-generating processes such as drilling, welding, or sanding
  • During fires

Through

  • Aerosols
  • Vapors
  • Dust that may contain unreacted chemicals

Hazards

  • Asthma
  • Sensitization
  • Lung damage
  • Other respiratory and breathing problems
  • Skin and eye irritation

Re-entry

  • Some manufacturers recommend 24 hours after application for worker re-entry without the use of PPE and for re-occupancy by residents and other building occupants, but the recommended time may vary. Contact your manufacturer or supplier for specific guidance.

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View spray polyurethane foam (SPF) comparison chart.

Uses

Sealant for filling cracks, holes, gaps, and crevices:

  • Around windows and doors
  • For sealing up small gaps (0.5" - 3") in a building to create an energy efficient building envelope

Note about use

This product is inappropriate for "creative" uses such as science or art projects and should not be used around children.

Applicator

  • Professional installer
  • Weatherization worker
  • Available for do-it-yourself applicators but note that the same precautions should be taken as with professional-use

Container size

  • Available in retail and hardware stores nationwide in a variety of sizes ranging from 12 oz. to 24 oz. cans

Engineering controls

Personal protective equipment (PPE)

  • Eye protection
  • Chemical resistant clothing
  • Chemical resistant (e.g., nitrile) gloves so that no skin is exposed

Avoid breathing vapors and provide adequate ventilation. Consult safety data sheets for additional respiratory guidance when needed. Ensure all equipment is intact upon use and ensure proper equipment maintenance. Vacate all unprotected workers and building occupants.

Chemical composition

  • SPF products contain approximately 50 percent Side A and 50 percent Side B. This chemical reaction generates heat. Side A contains very reactive chemicals known as isocyanates. Side B contains a polyol, which reacts with isocyanates to make polyurethane, and a mixture of other chemicals, including catalysts (which help the reaction to occur), flame retardants, blowing agents and surfactants.

Application process

  • OCF components are pre-reacted and undergo further reaction with ambient moisture at the time of application (moisture cured). Applied as stream or bead. May be trimmed or sanded.

Chemical exposure potential

May be exposed to chemicals

  • During application
  • After application
  • During heat-generating processes such as drilling, welding, or sanding
  • During fires

Through

  • Aerosols
  • Vapors
  • Dust that may contain unreacted chemicals

Hazards

  • Asthma
  • Sensitization
  • Lung damage
  • Other respiratory and breathing problems
  • Skin and eye irritation

Re-entry

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