Spray polyurethane
foam (SPF) is a highly-effective and widely used insulation and air sealant
material. However, exposures to its key
ingredient, isocyanates, and other SPF chemicals in vapors, aerosols, and dust
during and after installation can cause asthma, sensitization, lung damage,
other respiratory and breathing problems, and skin and eye irritation. Manufacturers, sellers and installers of
these products always make the claims that they are non-toxic without providing
any or providing very limited documentation.
We do know for sure
that the prevalence of asthma in the overall United States population has increased
by almost 100 percent since the early 1980’s and links have been reported
between these foams and the asthma or dermatitis incidents. A study that was done by Krone, et al. and
published in Environmental Contamination
and Toxicology in 2003 showed that isocyanates in foam containing consumer
products were present 30 years post-manufacture. We certainly concur with these findings as
the gloves we bought 27 years ago that caused us contact dermatitis in 1987 are
equally “effective” today in causing us the same effects. Now we place these products in our walls,
roofs, basements, everywhere in our homes by blindly listening to the claims of
the manufacturers and sales people. Are
we bringing the devil in? Are these
products wolves dressed in sheep’s skin?
Individuals with a
history of skin conditions, respiratory allergies, asthma, or prior isocyanate
sensitization should carefully review product information when considering the
use of SPF products and may want to consider safer alternatives. Manufacturers recommend in their isocyanate
safety data sheets that individuals undergo medical surveillance prior to
working with these materials and individuals with a history of medical
conditions as described above will be restricted from work with isocyanates.
Environmentally
friendly doesn’t necessarily mean worker friendly. In many cases, new “green” technologies and
products, such as SPF, have reached the market without being adequately
evaluated to determine whether they pose health or safety risks to workers in
manufacture, deployment, or use. Its use
as insulation has been on the increase because of the aim of builders and home
or building owners to improve energy efficiency and to assist with the
“greening” of the earth. As popular as
it has become, however, much remains unknown about spray polyurethane
foam—specifically the health implications of its amines, glycols, and phosphate
upon workers and the public. In fact,
the US EPA, NIOSH and the CDC only recently started looking into the effect of
these products when applied inside people’s homes or in
commercial/institutional settings. On
the other hand, there are quite a few reports about individuals, either workers
or homeowners, who experienced adverse health effects when came in contact with
these products. One case in point is the
foam used to make mattresses: some, but
not all, individuals have experienced the symptoms stated earlier (asthma, skin
and eye irritation, and so on).
Polyurethane
foam has a high R-factor (or R-value), so it resists the flow of heat and, when
used as insulation, increases a building’s energy efficiency. Because of this,
it has become a favorite in the world of energy-conscious construction and
renovation. While better insulation clearly means less energy consumption,
what’s not clear is the level of protection and ventilation workers need so
that they remain safe during the installation process. We have included quite a few pictures in this
blog showing workers not wearing the recommended personal protection when they
apply the chemicals.
We want to point out
that the residents or employee exposure to the isocyanates is an emerging
health issue and that very few epidemiologic studies are currently available on
acute or long term effects on properly installed polyurethane foam. However, if an installation is not properly
done, then the risk is there for acute and chronic effects to the building
occupants – there is no argument about that.
IN JULY 2014, CALIFORNIA PROPOSED TO IDENTIFY A SPRAY FOAM INGREDIENT, MDI, as a Toxic Air Contaminant Especially Affecting
Infants and Children
Under
Health and Safety code Section 39669.5, California’s Office of Environmental
Health Hazard Assessment (OEHHA) establishes and maintains a list of Toxic Air
Contaminants (TACs) that may disproportionately impact infants and
children. OEHHA evaluates TACs for
addition to this list as we develop Reference Exposure Levels for TACs. Monomeric methylene diphenyl diisocyanate
(MDI) and polymeric MDI, was identified by the Air Resources Board (ARB) as a
toxic air contaminant (TAC) in accordance with section 39657(b) of the
California Health and Safety Code (Title 17, California Code of Regulations,
section 93001) (CCR, 2007). MDI has been
shown to cause asthmatic reactions in sensitized asthmatic adults in controlled
exposure studies, and in non-sensitized children with asthma as well as
asthma-like effects in normal children exposed acutely to the diisocyanate MDI
in an accidental exposure (Jan et al., 2008). OEHHA considers asthma a disease
that disproportionately impacts children, and thus chemicals that induce or
exacerbate asthma are considered more impactful for children (OEHHA, 2001). In addition, an animal study has shown that
younger rats are more sensitive to the acute effects of MDI than young adult
rats (Reuzel et al., 1994b). In view of
the potential of MDI to exacerbate asthma and the differential impacts of
asthma on children including higher prevalence rates, OEHHA recommended in July
2014 that MDI be identified as a TAC that may disproportionally impact children
pursuant to Health and Safety Code, Section 39669.5(c).
What is Spray
Foam?
Spray
polyurethane foam (SPF) is a spray-applied plastic that can form a continuous
insulation and air sealing barrier on walls, roofs, around corners, and on all
contoured surfaces. It is made by mixing
and reacting unique liquid components at the job site to create foam. The liquids react very quickly when mixed,
expanding on contact to create foam that insulates, seals gaps, and can form
moisture and vapor barriers. SPF
insulation is known to resist heat transfer extremely well, and it offers a
highly effective solution in reducing unwanted air infiltration through cracks,
seams, and joints.
Types of
Spray Polyurethane Foam
There are
three primary types of SPF that can be used for insulation and other specific
purposes:
High Density:
often used for exterior and roofing
applications
Medium
Density: often used for continuous insulation,
interior cavity fill, and unvented attic applications
Low Density: often used for interior cavity fill and unvented attic
applications
Medium and
High Density SPF are frequently called “closed-cell foam” because they use an internal
closed cell structure that improves thermal resistance and other properties.
Low Density SPF is frequently called “open-cell foam” because the cell
structure includes tiny holes in the cells to provide improved drying
capability and flexibility. Each product
offers unique benefits that a professional SPF contractor can explain and help people
determine which types of foam will be most appropriate for a specific building,
climate, and project. Beyond the structure of the foam itself, the other
significant difference relates to how it is created and installed. The main delivery systems include:
•
High-pressure, two-component foam
•
Low-pressure, two-component foam SPF kits
High-pressure,
two-component foam is often used to insulate large areas on new
construction or major renovations of walls and roofing systems. For a typical
high-pressure SPF application, a spray rig (truck or trailer) that houses the
spray foam ingredients, air supply and other items is parked near the building
to be sprayed. Hoses up to about 300 feet in length deliver the liquid ingredients
to the application area.
Low-pressure,
two-component SPF kits or refillable
cylinders are smaller, portable systems that can insulate and air-seal small to
mid-sized areas. This type of foam is usually applied around duct work,
electrical or piping penetrations, rim joists and roof repairs. Both
high-pressure and low-pressure foams are applied by professional spray foam
applicators.
Chemicals
Overview of
Spray Polyurethane Foam
Spray
polyurethane foam is a thermoset cellular plastic insulating material formed by
combining methylene diphenyl diisocyanate (MDI) and a polyol blend. The reaction between these two materials
releases heat and within a few minutes foam is formed and is typically no longer
tacky or sticky. In the United States,
MDI is known as the A-Side (or Component A) and the polyol blend is known as
the B-Side (Component B).
Component
Materials Health Risks
MDI (A-Side
or Isocyanate Side):
MDI has a
potential risk of irritation and sensitization through inhalation and skin
contact. Exposure can affect skin, eyes,
and lungs. Once sensitized, continuing exposure can cause persistent or
progressive symptoms and even life-threatening asthmatic reactions, so remove
sensitized people from potential exposure activities. Wear the proper personal protective equipment
(PPE) when working with MDI.
See the manufacturer’s
Material Safety Data Sheet (MSDS) for more detailed information on potential health
effects.
Polyol
Blend (Resin or B-side):
The
B-side formulations for SPF use five basic chemical classes: polyols, blowing
agents, catalysts, flame retardants and surfactants. The polyol blend has a potential health risk
of irritation to the respiratory system, skin, and eyes. Wear the proper PPE
when working with polyol blends. See the
manufacturer’s MSDS for more detailed information on potential health effects.
Cured
Foam:
The
polyurethane foam that forms from the reaction of the A- and B-side chemicals
is considered essentially inert and non-hazardous when properly installed and
cured. Avoid exposing the polyurethane foam to extreme heat (>200°F) or open
flame due to the possibility that such extreme heat can ignite the foam.
OUR PERSONAL CONTACT WITH THE ISOCYANATES
In 1987 I purchased
a pair of leather gloves lined with wool for the cold winters of Illinois. Immediately after I wore then for an hour or
so I developed a very significant rush in both of my hands, along with
swelling. My hands almost doubled in
size. I removed the gloves and within
few days my hands were back to normal.
Few weeks later, I tried the gloves again, only to have the same
reaction. I then realized that something
is wrong with these gloves. I had them
tested at the University chemistry lab and the results came positive for
isocyanates and particularly MDI.
Apparently, the isocyanates are combined with other polymers to enhance
adhesion performance of the synthetic textile fibers. I was allergic to these isocyanates. After I got my PhD in Environmental
Engineering, I became more intimately familiar with the manufacture and application
of these compounds in everyday life.
They are everywhere. Some people
are allergic to some of them, other people are allergic to different compounds. I am not allergic to fiberglass insulation,
but my brother in law will develop blisters even if he comes close to it. So, we believe that there are people who are
sensitive to the chemicals and may develop allergies, asthma and other health
issues.
I
worked in the theatrical scenery industry for 20 years for a company with no
respiratory protection program, where urethane spray foam was used constantly. The thing about spray foam is that is doesn’t
have an overpowering odor, which makes one less concerned about breathing the
vapors. Stronger labeling by
manufacturer’s right on the canisters such as a big red WARNING sign would be
helpful for people who are not instructed properly and the employer does not
provide MSDS. In my last year at that
company I developed chest pains and breathing problems. I did not suspect it was urethane vapors
making me so ill. Improper mixing will
also sometimes emit liquids that will never solidify and leak into wood and
other porous materials. Spray foam is
used commonly in the theatrical industry for such things as texture, large
sculpture, and other applications that it is not intended for.
WHAT ARE THE ISOCYANATES?
Isocyanates have been
used in the United States since the 1950s, and are produced by reacting a
primary aliphatic or aromatic amine dissolved in a solvent such as xylene or
monochlorobenzene with phosgene dissolved in the same solution. They contain two OASH-NCO cyanato groups
attached to an organic radical, and react exothermically with compounds
containing active hydrogen atoms to form a polymeric mass (polyurethane). This
polyurethane is then used in the production of rigid or flexible foams, surface
coatings, paints, electrical wire insulation, adhesives, rubbers and fibers.
The most common forms
of isocyanates are toluene diisocyanate (TDI) and methylene diphenyl
diisocyanate (MDI) and Hexamethylene Diisocyanate (HDI). TDI is popular for producing many paints and
coatings, along with flexible foam, which is used in making cushions for
automobiles, furniture and mattresses. MDI
is commonly used in the production of adhesives, automobile bumpers, shoe
soles, coated fabrics and spandex fibers. It can also be found in paints.
MDI is used in the
manufacturing of rigid foams, and must be heated before causing asthma-like
conditions when inhaled as an aerosol. This
makes MDI somewhat less hazardous than TDI, so it has been replacing TDI in
certain applications. HDI is mainly used
to make polyurethane foams and coatings it is also used as a hardener in in
automobile and airplane paint. Exposure can cause an allergic asthma-like
response with coughing, wheezing and shortness of breath.
Some less common
forms of isocyanates include:
o
napthylene
diisocyanate (NDI)
o
polymethylene
bisphenylisocyanate (PAPI)
Asthma and other Effects of Isocyanates
Isocyanates have been
determined to be the leading attributable cause of work-related asthma (NIOSH,
2004). TDI is a liquid at room
temperature, and can cause asthma-like conditions when inhaled as an aerosol
(such as spray paint). Repeated exposures to isocyanates have been
shown to exacerbate existing asthmatic conditions (Mapp, 2005). Isocyanates are the key materials used to
produce polyurethane polymers. These
polymers are found in common materials such as polyurethane foams,
thermoplastic elastomers, spandex fibers, and polyurethane paints. Isocyanates
are the raw materials that make up all polyurethane products. Exposures may also occur during the thermal
degradation of polyurethane products (e.g., burning or heating at high
temperatures).
OSHA has Permissible
Exposure Limits (PELs) for Methylene bisphenyl diisocyanate (MDI) and
2,4 toluene diisocyanate TDI of 0.02 ppm. This corresponds to
0.20 mg/m3 for MDI and 0.14 mg/m3 for TDI. Health effects of isocyanate exposure include
irritation of skin and mucous membranes, chest tightness, and difficult
breathing. Isocyanates include compounds classified as potential human carcinogens and known to cause
cancer in animals. The main effects of hazardous exposures are sensitization
which can lead to work-related
asthma (sometimes
called occupational asthma) and other lung problems, as well as irritation of
the eyes, nose, throat, and skin.
Below is a list of
jobs with potential isocyanate exposures and materials that may contain
isocyanates. It is important to understand additional sources of
isocyanate exposures, especially for those already sensitized or with asthma,
in order to avoid exacerbating an existing asthmatic condition. Because
isocyanate exposures can occur across multiple jobs, it is important to
understand where prior exposures have occurred. In addition to SPF
applications, OSHA has identified the following industries where Isocyanate
worker exposures can occur – some of which use a similar material to SPF (in
bold):
Potential Jobs-Related Isocyanate Exposures
·
Automotive
- paints, glues, insulation, sealants and fiber bonding, truck bed lining
·
Casting
- foundry cores
·
Building and
construction
- in sealants, glues, insulation
material, fillers
·
Electricity
and electronics - in cable insulation, PUR coated circuit boards
·
Mechanical
engineering - insulation material
·
Paints
– lacquers
·
Plastics
- soft and hard plastics, plastic foam and cellular plastic
·
Printing
– inks and lacquers
·
Timber
and furniture - adhesive, lacquers, upholstery stuffing and fabric
·
Textile
– synthetic textile fibers
·
Medical
care – PUR casts
·
Mining – sealants and
insulating materials
·
Food
industry – packaging materials and lacquers
·
Shipbuilding
·
Firefighting
Isocyanate Exposure
Levels
The OSHA
permissible-exposure limit (PEL) for TDI and MDI is 0.02 ppm of air as a
ceiling limit. The ceiling is the highest concentration to which an employee
can be exposed. The American Conference of Governmental Industrial Hygienists
(ACGIH) recognizes 0.005 ppm as its threshold-limit value (TLV) as an
eight-hour time-weighted average and 0.02 ppm as a short-term exposure limit
(STEL) for TDI, MDI and HDI.
Air Monitoring for
Isocyanate
OSHA test method 42
(for TDI and HDI) and method 47 (for MDI) spell out personal-monitoring
procedures for isocyanates. Samples are to be collected by drawing a known
volume of air through glass fiber filters with a recommended air volume and
sampling rate of 15L at 1L to 2L per minute.
You can also conduct
continuous isocyanates monitoring. Many companies offer single-point monitors
that can continuously monitor isocyanates for up to one month. They operate by
an electro-optical sensing system, which uses a cassette-like tape. A stain
occurs on the tape, and is then read in proportion to the concentration of the
isocyanate.
Different cassette
tapes are available. Standard-play tapes are replaced every two weeks. Extended
play tapes last for a month. Datalogging monitors with alarms are also
available. These types of monitors are ideal in spray-booth operations.
Effects of Isocyanate
Overexposure
Exposure to
isocyanates can lead to chemical bronchitis and pneumonitis. An isocyanate
reaction often includes coughing, tightness of the chest, shortness of breath,
nausea, vomiting, eye and skin irritations, gastric pain and loss of
consciousness.
Continuous
overexposure to isocyanates can lead to pulmonary sensitization or "isocyanate
asthma." When this occurs, symptoms improve when the irritant is removed.
However, acute asthma attacks occur on renewed exposure, even when the
encounter is very brief or at low levels of isocyanates, and can cause death.
Skin contact can
cause inflammation and necrosis, which might lead to dermatitis. Wash hands
with soap and water immediately upon contact.
Personal Protective
Equipment for Handling Isocyanates
Prior to OSHA’s
revision to the respiratory protection standard (April 8, 1998) supplied air
respirators were required to help reduce exposures to isocyanates, this was
appropriate due to the poor warning properties of isocyanates. Now air purifying respirators may be used for
those compounds that have poor warning properties if the cartridge change
schedule is set up. This is because
cartridge change schedules are required instead of workers relying on warning
properties of compounds for cartridge change out. Properly selected and used air-purifying
respirators can be used to safely and effectively to reduce exposures to common
diisocyanates. Appropriate cartridge change schedules should be developed to
ensure cartridges are changed before breakthrough occurs. OSHA allows employers to choose air-purifying
respirators for diisocyanates if they are appropriate for their
workplace. A complete respiratory protection program per 29 CFR 1910.134
is necessary to ensure that respirators are selected properly and provide
appropriate protection.
Isocyanates are also
a hazard to the skin, hand protection such as Butyl rubber gloves or SilverShield®/4H
gloves can adequately protect hands from isocyanates. Chemical protective
clothing that is rated for use to protect against isocyanates is also
suggested.
Eye and face
protection may also need to be considered for on the job protection as
isocyanates are known to be an irritant to the eyes.
References
National Institute
for Occupational Safety and Health. Worker Health Chartbook 2004. NIOSH
Publication Number 2004-146
Mapp CE, Boschetto P,
Maestrelli P, Fabbri LM. (2005) Occupational Asthma. Am J Respir
Crit Care Med 172; 28/0-305.
3M Job Health
Highlights-Respirator Selection for Diisocyanates, Vol 18, August, 2009
American Journal of
Industrial Medicine
13:331-349 (1988) "Isocyanates and Respiratory Disease Current
Status"
Clinical Allergy.
1984, Volume 14, p.329-339.
IN 2011, THE US. EPA DEVELOPED AN ACTION PLAN FOR SPRAY
POLYURETHANE FOAM
Based on EPA’s
screening-level review of hazard and exposure information, including
information indicating uncured MDI and its related polyisocyanates are used in
a range of consumer and commercial products as well as in products intended
only for an industrial market, EPA intends to:
1. Issue a data
call-in for uncured MDI under TSCA section 8(c) to determine if
there are allegations of significant adverse effects and initiate a TSCA section 8(d) rulemaking for
one-time reporting of relevant unpublished health and safety studies for
uncured MDI.
2. Consider
initiating a TSCA section 4 test rule to require
exposure monitoring studies on uncured MDI and its related polyisocyanates in
consumer products and exposure monitoring studies in representative locations
where commercial products with uncured MDI and its related polyisocyanates
would be used.
3. Consider
initiating rulemaking under TSCA section 6 for
a. Consumer products
containing uncured MDI, and
b. Commercial uses of
uncured MDI products in locations where the general population could be
exposed.
4. Consider
identifying additional diisocyanates and their related polyisocyanates that may
be present in an uncured form in consumer products that should be evaluated for
regulatory and/or voluntary action.
Material
(components of SPF and the final product)
Material
Safety Data Sheet (MSDS): Employers are required
by OSHA to provide training on MSDSs and employees need to have a full
understanding of the contents of an MSDS. Employers are also required by OSHA
to have MSDSs readily available on jobsites. Here is an overview of the key
sections of most MSDSs for SPF-related chemicals:
Name of
Product or Chemical:
•
Component A (isocyanate)
•
Component B (typically includes: polyol, amine catalyst, blowing agent, fire
retardant, surfactant)
• Solvents
• Cleaning
solutions
• Coatings
Potential
hazards:
• Acute
and chronic toxicity
•
Irritation
•
Sensitization
Personal
protection equipment (PPE):
•
Respiratory protection
• Eye
protection
• Gloves
•
Disposable coveralls or clothing that protects against exposure
• Boot
covers (resistant to wear)
Storage and
handling of the chemicals:
• Proper
storage conditions for the materials
•
Procedure and equipment/supplies to properly contain and clean a spill
Procedures in
case of an accidental exposure or overexposure:
•
First-aid procedures
• First
aid materials to keep on the jobsite
Other
information that is provided in an MSDS:
•
Fire-fighting measures
• Physical
and chemical properties
•
Stability and reactivity
•
Toxicology
• Disposal
•
Transportation
•
Regulatory information
Applicable
Safety Standards
When
establishing jobsite safety standards, a company needs to refer to the
applicable safety standards. These can include, but are not limited to, the
following OSHA standards:
• Hazard
Communication: 29 CFR 1910.1200 and 1926.59
•
Respiratory Protection: 29 CFR 1910 Part 134
• Personal
Protective Equipment: 29 CFR 1910 Part 132-138 and 1926.95
• Ventilation:
29 CFR 1910.94 and 1926.57
Jobsite
Preparation
Like
all field-applied foams and coatings, quality control and quality assurance is
critical to the successful performance of SPF roof systems. But unlike many other roofing materials, an
SPF roof is assembled in the field. Materials
such as extruded polystyrene foam, single-ply membranes of EPDM and TPO, and
form flashings are manufactured in controlled production settings with rigorous
quality processes in place. Manufacturing
plants are equipped with automated systems to control temperature and humidity
or to catch pumps that go off ratio so that corrections can be made before
multiple runs of material are manufactured improperly.
Since
SPF serves as the thermal boundary, moisture barrier and flashing, quality
control is extremely important during application to ensure the system is
properly “site-manufactured.” A successful application of SPF depends heavily
on the applicator’s skill and the employment of a
quality-control/quality-assurance plan to establish that the substrate is
properly prepared, that the foam mix ratio is correct, and that proper ambient
conditions are maintained.
Continuous
field quality control/quality assurance is necessary throughout the application
process in order to achieve a successful SPF application.
Key materials used in SPF systems include
spray polyurethane foam and protective surfacing. Primers can be used to facilitate adhesion,
but are not a substitute for proper surface preparation
There are
many factors to consider when planning any SPF installation, such as the place
of work, area of building occupancy, size of work area, and many others. Assess any special requirements or risks
before the job starts and develop a plan to address them. Understanding ventilation requirements is
essential. For example, shut down HVAC
systems during a SPF application. System
shut-down stops dust, aerosol and vapors from being drawn into the HVAC
system. For interior applications, this
can help prevent airborne materials from being distributed from one part of a
building to another. Once the HVAC
system is shut down, seal the air intakes with plastic sheeting and tape to
prevent dust and spray from entering the system. Some SPF manufacturers recommend that the
HVAC system stay sealed and inoperable for up to 24 hours after the SPF
application. Individual SPF
manufacturer’s recommendations concerning re-occupancy supersede any general
recommendation. Once you determine when
an appropriate time has elapsed, based on the manufacturer’s recommendation,
remove the plastic sheeting and tape.
General
Preparation Steps
There
are several steps to consider prior to the actual application of the foam
insulation. Examples of steps to consider include:
1. Provide a briefing for the general
contractor and/or owner of the building so they can better understand the scope
of the work and the safety procedures to utilize during the application
process.
2. Confirm necessary inspections associated
with the other trades have been completed and approved prior to the
installation of the insulation.
3. Confirm all permits are in place prior to
the spraying operation.
4. Complete other trade work to avoid later
disturbance of insulation.
5. Install warning signs and caution tapes.
6. Clear building occupants and non-SPF
personnel from building. Consider utilizing the best practices for the use of
containment and ventilation techniques detailed in the U.S. Environmental
Protection Agency’s “Ventilation Guidance for Spray Polyurethane Foam
Application”: http://www.epa.gov/dfe/pubs/projects/spf/ventilation-guidance.html
7. Designate an area for putting on and
removing PPE.
Jobsite
Crews and Safety Briefings
Many
commercial jobsites may require contractors to conduct safety briefings with the
jobsite crews. They may require that documentation of meetings be submitted to
the general contractor for the project. As a good safety practice, companies
may consider implementing this policy regardless of whether the job is
residential or commercial in nature. The
Daily Work Log outlined in the previous section (3.1) can provide a helpful
structure for developing your own work log. Daily Work Logs are also a method
for improving record keeping.
Notice
to Other Trades and Occupants
Vacate
building occupants and non-SPF personnel from the building during the
application of SPF and for a period of time following the completion of
spraying. Where this is not possible or practical for large commercial
buildings, the use of containment and ventilation techniques can be
utilized. For residential applications,
the homeowner needs to vacate the home and return only after the specified
re-occupancy time. Communicate with
other trades working in proximity to the spray application area. Giving notice
to other trades is an important aspect on larger commercial projects due to the
number and kinds of workers in and around the jobsite.
The focal
points for this communication are the general contractor, building owner, home
owner, or other responsible personnel for the project. Educate the onsite
supervisor or project manager at the start of the project long before the
actual spray application starts so that they have a complete understanding of
the jobsite safety requirements before the beginning of the spray application
process. Critical jobsite safety concerns include proximity of open flame
sources and personnel to the spray application area.
General
Safety Considerations
After the
spray application area is secured, check the overall area and extinguish all sources
of flame (e.g. pilot lights). Also, check for flue piping, lighting fixtures,
and other heat producing devices.
Set up and
prepare the necessary ladders, scaffolding, aerial lifts, and rigging. Once set
up, perform a safety check of all the equipment to check that it is properly
assembled, nothing is broken or missing, and that all safety devices are
operational and in place. Check walking and work surfaces and the routing and
location of process equipment hoses and electrical cords as they can present a
trip hazard. If gas powered equipment is in use, vent the exhaust fumes to an
open environment in order to limit the risk of a buildup of carbon monoxide in
the work area.
Lockout/Tagout
Some
projects may present instances where you want to consider locking out/tagging
out of equipment. Lockout/tagout includes practices and procedures to safeguard
employees from the unexpected energizing or startup of machinery and equipment,
or the release of hazardous energy during service or maintenance activities.
For work near energized equipment, contractors should follow the OSHA standards
(29 CFR § 1926.417 or 1910.147). The SPF contractor coordinates with the
appropriate facility personnel for locking/tagging out equipment.
Ventilation
Considerations
Another jobsite
consideration is ventilation. Turn off HVAC duct system fans and seal them so
overspray does not enter the duct system. If gas powered equipment is used,
direct the exhaust fumes to an open environment to prevent a buildup of carbon
monoxide in the work area.
If
evacuating an entire commercial building is not practical or possible, consider
the potential for SPF chemicals to migrate to other floors. Containment and
ventilation methods help prevent migration of chemicals and particulates.
Discussing the project and application with property management and other
contractors in areas or floors that will remain occupied during the period of
SPF application is an important consideration.
Spray foam insulation is the target of
civil complaints filed in federal district courts. Federal lawsuits claiming that
spray-polyurethane foam insulation is toxic and can sicken those who live in
houses where it has been installed are pending in more than a half-dozen
states.
To date, complaints
have been filed in federal district courts in Florida, New York, Michigan, New
Jersey, Connecticut, Wisconsin, and Pennsylvania, Claims are pursued against a
number of different manufacturers and installers, including Demilec, Lapolla, Masco,
and NCFI Polyurethanes. We believe that
it will be difficult to win these class action cases, as the SPF can be safe if
properly applied. The individual
lawsuits could be more successful, though, depending on the sensitive
population impacted, namely children and infants and certain adults.
Health Concerns
Spray polyurethane
foam (SPF) is a highly-effective and widely used insulation and air sealant
material. However, exposures to its key
ingredient, isocyanates, and other SPF chemicals in vapors, aerosols,
and dust during and after installation can cause asthma, sensitization, lung
damage, other respiratory and breathing problems, and skin and eye irritation.
Individuals with a
history of skin conditions, respiratory allergies, asthma, or prior isocyanate
sensitization should carefully review product information when considering the
use of SPF products and may want to consider safer alternatives. Manufacturers recommend in their isocyanate
safety data sheets that individuals undergo medical surveillance prior to
working with these materials and individuals with a history of medical
conditions as described above will be restricted from work with isocyanates.
- Health Concerns Associated with Side A: Isocyanates
- Health Concerns Associated with Side B: Polyol Blend
Isocyanates are a
class of highly reactive chemicals with widespread industrial, commercial, and
retail or consumer applications.
Exposure to isocyanates
may cause skin, eye and lung irritation, asthma, and “sensitization.” There is
no recognized safe level of exposure to isocyanates for sensitized individuals.
Isocyanates have been reported to be the leading attributable chemical cause of
work-related asthma. Both dermal and respiratory exposures can trigger
adverse health responses.
EPA, other federal
agencies, states, industry, and other countries have taken a variety of actions
to address risks posed by exposure to isocyanates.
Exposures
to isocyanates should be minimized. The following were noted in the NIOSH Alert,
Preventing Asthma and Death from MDI Exposure during Truck Bed Liner and
Related Applications.
- Isocyanates have been reported to be the leading attributable chemical cause of work-related asthma, a potentially life-threatening disease.
- Exposure to isocyanates can cause contact dermatitis, skin and respiratory tract irritation, sensitization, and asthma.
- Both skin and inhalation exposures can lead to respiratory responses.
- Isocyanates can cause “sensitization,” which means that some people may become allergic to isocyanates and could experience allergic reactions including: itching and watery eyes, skin rashes, asthma, and other breathing difficulties. Symptoms may also be delayed up to several hours after exposure. If you are allergic or become sensitized, even low concentrations of isocyanates can trigger a severe asthma attack or other lung effects, or a potentially fatal reaction. There is no recognized safe level of exposure to isocyanates for sensitized individuals.
- Some workers who become sensitized to isocyanates are subject to severe asthma attacks if they are exposed again. Death from severe asthma in some sensitized persons has been reported. NIOSH issued an earlier Alert in 1996, “Preventing Asthma and Death from Diisocyanate Exposure."
- Sensitization may result from either a single exposure to a relatively high concentration or repeated exposures to lower concentrations over time; this is an area where additional research is needed.
- Even if you do not become sensitized to isocyanates, they may still irritate your skin and lungs, and many years of exposure can lead to permanent lung damage and respiratory problems.
- All skin contact should be avoided since contact with skin may lead to respiratory sensitization or cause other allergic reactions. Appropriate personal protective equipment (PPE) should be used during all activities that may present exposure to any isocyanate compounds to avoid sensitization.
Side B contains a blend
of proprietary chemicals that provide unique properties in the foam, and may
vary widely from manufacturer to manufacturer.
- Catalysts may be amine or metal catalysts
- Amine catalysts in SPF may be sensitizers and irritants that can cause blurry vision (halo effect)
- Flame retardants, such as halogenated compounds, may be persistent, bioaccumulative, and/or toxic chemicals (PBTs). Some examples include:
- TCPP -(Tris(2-chloroisopropyl)phosphate)
- TEP -(Triethyl phosphate)
- TDCP -(Tris (1,3-dichloroisopropyl) phosphate blend)
- Blowing agents may have adverse health effects
- Some surfactants may be linked to endocrine disruption
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Losing their health and homes to spray polyurethane foam
© Lloyd
Alter
This article is the first of a series examining the risks associated
with spray polyurethane foam. When Keri Rimel's husband first came down with respiratory symptoms, he wasn't sure what caused them. He had a sore throat, congested sinuses, and runny eyes.
The day before, he has visited the construction site of their new home, where a contractor was installing spray polyurethane foam insulation. He and the architect were in the same room as the installer. "He didn't think anything of it," said Keri Rimel.
Their house in Austin, Texas was a new build. They had chosen Demilec's Sealection 500 spray foam as the only insulation and it filled every exterior wall cavity of the structure and the roof. Whenever he went back into the house, his symptoms would return.
"As soon as I went into the house, the smell would be overwhelming and my throat would clog up."
Keri experienced symptoms herself when she visited the house. "As soon as I went into the house, the smell would be overwhelming and my throat would clog up," she said. "I would get chest pain on the left side of my chest. That always happened.”Spray foam is often touted as a green building material because of its high insulation value and tight seal, which can make homes more energy efficient. The American Resource and Recovery Act of 2009 promoted spray foam as a source of green jobs that provides energy efficiency. According to the industry group Spray Foam Coalition, sales increased 29 percent from the first half of 2010 to the first half of 2012. Another industry report predicts spray foam sales to increase by 15 percent annually.
Yet as more homes and buildings are insulated with spray foam, a growing number of consumer advocates and green builders are concerned about the growing use of a product made from a number of toxic components. At the same time, homeowners around the U.S. are reporting serious health issues following the installation of spray foam or moving into a new home insulated with spray foam.
Spray foam insulation is produced during installation by mixing two liquid chemical components, referred to as "Side A" and "Side B." The liquid is then applied to the wall or ceiling with a spray gun, where it reacts and expands. Although there are toxicants in both Side A and Side B and installers are instructed to wear full body haz-mat suits, spray foam manufacturers say the final "cured" product is inert.
"The products are safe, There are no issues. The products become inert. There's no long term effect and we have over 25 plus years of history in this marketplace."
"We do standard [Volatile Organic Compound] analysis on all of the products that go to market," said Robert Naini, the chief operating officer of Demilec, one of the largest manufactures of spray foam. "It's lab testing done as part of our procedures." Volatile Organic Compounds (VOCs) are chemicals with negative health effects that off-gas from a variety of solid or liquid products. Naini said that all of their products meet several established guidelines for low-emissions products, including LEED standards, standards set by the California Department of Public Health, and GreenGuard certification."The products are safe," said Naini. "There's no issues. The products become inert. There's no long term effect and we have over 25 plus years of history in this marketplace." Flickr/CC BY 2.0
According to the Environmental Protection Agency and the Centers for Disease Control, the issue of off-gassing is less clear-cut. The EPA recently launched a webpage dedicated to reducing the risk of chemical exposure from spray foam, which states, "The potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed."
Another issue is reentry time, or in other words, when is it safe to be around spray foam without protective garments after installation? The Centers for Disease Control is currently researching this question, but some manufacturers estimate as little as seven hours while others say as many as 72 hours. There are many factors that can impact curing rates, included the type of spray foam, the humidity, the thickness of the foam, the ambient temperature, the temperature of the chemicals and the technique of the installer.
"The potential for off-gassing of volatile chemicals from spray polyurethane foam is not fully understood and is an area where more research is needed."
Whatever the conditions might have been, it was unsafe for Keri Rimel's husband to be in the house at the time of installation without protective gear according to the majority of manufacturing guidelines. "No one told us to be out of the house," said Keri.Rimel said the lingering chemical odor caused their building project to come to a halt. She and her husband delayed installing drywall to conduct air quality tests and attempted to ventilate their house. Eventually, they concluded that the foam had to be removed after testing indoor air quality tests found unacceptable levels of of VOCs, formaldehyde, acetaldehyde and hexanal. The written report from Argus Environmental, the company that conducted the testing, concluded that the Rimels should not occupy the home until the foam was removed.
But even after the spray foam had been removed, the chemical sensitization Keri and her husband suffer from made it impossible for them to stay in the house. "The fumes permeate everything," said Rimel. Even tiny amounts of chemicals can trigger their symptoms. After months of being unable to find a satisfactory solution, they sold the property.
"This new source of exposure potentially puts a large population at risk for adverse health effects."
In the March 2012 edition of the Journal of Occupational and Environmental Medicine, Dr. Yuh-Chin T. Huang and Dr. Wayne Tsuang describe a case similar to the Rimels. A couple in their 30's returned to their home four hours after spray foam was installed in the attic. They almost immediately began experiencing difficult breathing, coughing, nausea, headaches and watery eyes.The patients were diagnosed with asthma triggered by isocyanate, a chemical found in Side A and widely cited as the leading cause of occupational asthma. "The use of [spray polyurethane foam] in residential homes likely will continue to increase," they write. "This new source of exposure potentially puts a large population at risk for adverse health effects." The couple was eventually forced to leave their home after three months of trying to remediate both their symptoms and the lingering chemical odor.
Since publishing the article, Dr. Huang said he has been contacted by more than a dozen people who developed similar symptoms after being around spray foam. Although they call from around the country and he is not able to see them in person, he said most arrive at the same conclusion. "They cannot move back to their houses."
Chemicals in spray polyurethane foam: How can something so toxic be considered green?
CC BY
2.0 Flickr
Read Part 1 of this series: Losing
their health and homes to spray polyurethane foam.Spray polyurethane foam is widely promoted as a green building material for its ability to improve energy efficiency. It insulates better per inch than fiberglass or cellulose, which can mean major energy saving on heating and cooling. However, energy efficiency isn't the only consideration when it comes to sustainable building. A closer look at spray foam's chemical makeup reveals a number of substances that are known to be hazardous.
Spray polyurethane foam consists of two liquid chemical components, referred to as "Side A" and "Side B," that are mixed at the site of installation. Side A is mostly made up of isocyanates, while Side B usually contains polyol, flame retardants and amine catalysts. These chemicals create hazardous fumes during the application, which is why installers and nearby workers should wear personal protective gear during this process. Once the foam has fully expanded and dried, manufacturers say it is inert. If the chemicals are not properly mixed, they may not react fully and can remain toxic. Flickr/CC BY 2.0
The risks associated with the isocyanate of Side A are relatively well-documented, but risks associated with Side B are less well understood. David Marlow at the Centers for Disease Control has been researching off-gassing associated with spray foam installation since 2010. Although Marlow was unavailable for interview, the Public Affairs office at the CDC was able to provide information about his ongoing research via email. These field studies aim to determine the extent of exposure to all the chemical components of spray foam, determine a better understanding of curing rates and establish safe reentry times, and develop engineering controls to reduce the risk of exposure.
In addition to the dangers associated with installation, these chemicals can potentially remain unreacted in the form of dust or shavings. The Environmental Protection Agency warns: "Cutting or trimming the foam as it hardens (tack-free phase) may generate dust that may contain unreacted isocyanates and other chemicals." This is also a concern during the process of removing foam.
Isocyanates
Isocyanates, such as methylene diphenyl diisocyanate (DMI), are found in the "Side A" of the spray foam mix. Isocyanates are also found in paints, varnishes and other types of foam. They are a known cause of occupational asthma. According to Dr. Yuh-Chin T. Huang, a professor at Duke University Medical Center, isocyanate-induced asthma is similar to other types of asthma, but instead of being triggered by exercise, it is triggered by exposure. Once someone has become sensitized, re-exposure can cause intense asthma attacks.Homeowner Keri Rimel says she and her husband have both become extremely sensitive to isocyanates and other chemical smells following exposure during spray foam installation. "He still to this day can walk into any restaurant, home or office and he can immediately tell if there's spray foam in a building," said Rimel of her husband.
According to the CDC, direct contact with isocyanates can also cause a rash if it comes in contact with the skin.
Amine catalysts
Amine catalysts are one of the Side B chemicals that the CDC
is researching, in an effort to understand the levels of exposure during
installation. "Amine catalysts in [spray polyurethane foam] may be
sensitizers and irritants that can cause blurry vision (halo effect),"
they write.
According to a report
published by the Consumer Product Safety Commission, amine catalysts can
also irritate the eyes at even low concentrations and if ingested "may
result in severe irritation, ulceration, or burns of the mouth, throat,
esophagus, and gastrointestinal tract."Polyol
Also found in side B, polyols are alcohols that serve as catalysts. Polyols are usually made from adipic acid and ethylene glycol or propylene oxide. Some polyols are made from soy, but according to the Pharos Project, an organization that advocates for building material transparency, the soy-based material makes up just 10 percent of the final insulation.Ethylene glycol, a chemical used to produce polyol in some spray foam, can in cases of acute exposure (such as swallowing) cause vomiting, convulsions and affect the central nervous system. According to the EPA, exposure by inhalation can cause irritation in the upper respiratory system and studies in animals have shown kidney failure.
Flame retardants
Flame retardants are added to Side B to pass flammability tests in building codes. The main fire retardants used in spray foam are hexabromocyclododecane (HBCD or HBCDD) and tris(1-chloro-2-propyl) phosphate (TCPP).According to the Centers for Disease Control, "flame retardants, such as halogenated compounds, are persistent bio accumulative and toxic chemicals." Bioaccumulation means that a chemical builds up in the body faster than it can be flushed out, so there can be a risk of chronic poisoning even if the level of exposure is low. The chemicals also build up in the ecosystem, where they enter the food chain.
A paper by Vytenis Babrauskas published in the journal Building Research & Information says that, “flame retardants whose primary use is in building insulation are found at increasing levels in household dust, human body fluids and in the environment.” The paper also cites several other studies that show these chemicals are associated with endocrine disruption and are potentially carcinogenic.
The chemical question mark
In a post for the CDC, Marlow describes the components of Side B as "a chemical question mark." He described the need for "real world sampling."In addition to those listed above, there may be other chemicals used in spray foam that are undisclosed, and are protected trade secrets. This is particularly troubling for homeowners who want to have their air tested, because they won't know which tests to have done. "You have to tell the person testing what you're looking for," says Terry Pierson Curtis, an indoor air quality specialist. "The problem a lot of times is trying to figure out what you're looking for."
NEXT: Spray Polyurethane foam manufacturer may face class-action lawsuit
Weighing the Merits of Spray Foam Insulation
A homeowner gets conflicting advice on how to insulate a 90-year-old Cape Cod home
Posted on Jan 23 2012 by Scott
Gibson
Mulling the benefits of foam
A homeowner has bids from several contractors for insulating
his home with spray foam insulation, but conflicting advice has left him
puzzled.
Scott Jacobs’ 1,100-sq. ft. Cape is a perfect candidate for an energy
upgrade. The 90-year-old house is gutted, and Jacobs wants to insulate it well
even if his budget is not unlimited.The house, located in Climate Zone 6, now has a 1/2-in. thick layer of rigid foam on the exterior walls. Jacobs’ plan is to insulate the house from the inside with spray polyurethane foam.
“This is my problem,” Jacobs writes in a Q&A post at GreenBuildingAdvisor. “Three companies have provided estimates now. Two say open-cell foam, 7 in. to 8 in., on the roof and 3.75 in. on the walls. One company just quoted 7 in. open-cell foam on the roof and 2 in. closed-cell foam on walls. Estimates vary between $4,500 and $5,500.”
First, Jacobs wonders, how do the 2 in. of closed-cell foam compare with 3 3/4 in. of open-cell foam? And second, for someone with not much money to spend, would installing rigid foam insulation in the rafter bays himself be a reasonable option?
That’s the topic for this month’s Q&A Spotlight.
Open-cell vs. closed-cell foam
Jean-Paul McGraw sums up some of the basic differences between these two types of insulation, including R-values and cost.“The advantages of closed-cell foam compared to open-cell foam include its strength, higher R-value, and its greater resistance to the leakage of air or water vapor,” McGraw writes.
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Open-cell spray foam has an R-value of about 3.5 to 3.7 per inch and typically uses water as a blowing agent, while closed-cell foam has an R-value of about 6 per inch, he adds.
Costs, at least in McGraw’s area, average about 80 cents a square foot for open-cell foam and about $1.20 per square foot for closed-cell foam. With those R-values in mind, Jacobs will have trouble meeting energy code recommendations for his region if he goes with open-cell foam.
“A house in [Climate Zone] 6 requires R-49 insulation in the attic,” Armando Cobo says. “If your intention is to have a conditioned attic, 7.5 in. [of open-cell] foam is R-28, then you also need 3 in. minimum rigid insulation on top of the roof decking. If you want to install [closed-cell] foam, you would require 7.5 in., and it can only be installed in 2-in. applications.”
Cobo steers Jacobs toward a chart provided by Demilec, an insulation manufacturer, with more details.
“The companies that are proposing 7 inches of open-cell spray foam for your roof are only offering R-26,” adds GBA senior editor Martin Holladay. “That isn't much. In your climate zone, as Armando points out, you really want at least R-49. Don't let a spray-foam contractor talk you into accepting insulation that is less than the minimum code requirements.”
Energy codes aren’t everything
Energy codes may call for R-49 in the roof, but that doesn’t mean it’s absolutely necessary, some commenters argue.Among them is A.J. Builder in upstate New York, who writes that “code R-values do not factor in how well spray foam works compared to fiberglass of the same R value. Most times spray foam is not installed to code R values and yet it performs much better than fiberglass.”
Others go even further. Meeting the R-49 requirements is a “waste of money,” Eric Price writes.
“Eric is right,” adds John Pfeiffer. “IMHO the law of diminishing returns really takes a bite out of using more than 2 to 3 in. of closed-cell (depending on your location, I'm in southern N.Y., zone 4a). Don't trust the codes for telling you what is the most cost-effective way to insulate a house. They are written by people wearing suits and working in offices, not contractors.”
An R-40 roof may leak half the amount of heat as an R-20 roof, he says, but savings may amount to only pennies per square foot at the expense of adding twice the amount of insulation at double the cost.
“Also, consider what happens if your roof has a leak,” he adds. “Open-cell is a sponge and will need to be taken out and replaced; closed-cell won't show the leak and will soak the plywood until something gives.”
Our expert’s opinion
GBA technical director Peter Yost added this:Scott, it sure sounds as though you would like to optimize energy performance, taking advantage of the framing cavities being open, and do it as economically as possible, including DIY. Given all that, here are my recommendations:
- Get a sense of where to spend your money – the best two ways to do this, in my opinion, are to get a whole-house performance assessment done by a BPI-certified technician, and to use the LBNL Home Energy Saver Pro Energy Assessment Tool. I have used this on more than one project, and using the detailed assessment path, I have come within $100 of total household annual utility bills, and their recommendations are useful.
- Seriously consider the DIY rigid-foam approach to cavity fill. Yes, this is labor-intensive, but it is relatively easy to do, and you often can employ scraps of rigid foam or salvaged rigid foam insulation. The key is to not be too fussy about how your cuts fit, because you can’t cut it tight or well enough to be your air barrier anyway, so save the air sealing for later, when you spray foam all your joints and perimeters.
- Others have given solid guidance on choosing open-cell or closed-cell foam. On this, let me add that if you do choose a spray foam approach to cavity fill, be sure to use a certified installer.
- Evaluate your investment options. Martin and I just both wrote useful blogs on the topic of payback analysis – give those a look.
Tags: polyurethane
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