As the number of spray foam jobs increase there will be more cases that go awry. Its a huge subject with many variables and perspectives. Its kind of surprising to me that there arent more problems out there considering the many ways that it can get screwed up.

Ive spent more time than I care to admit researching spray foam and for the most part, Iam a fan. As long as one hires an experienced installer, they dont use old chemicals, spray wet surfaces or too thickly at once there's not much that can go wrong. Experienced installers (not salesman) are absolutely the most important ingredient.

There are certainly indoor air quality concerns even for well done installations. That's true for almost all building materials and according to NIOSH, accounts for only 4% of indoor air quality concerns. Indoor Air Quality is best served by a permanent mechanical ventilation system providing fresh air introduction from the outdoors.

Rigid is much safer as its done in a controlled environment. Its also usually more separated from the interior air in typical installations.

Foam in general is airtight, has the highest R per inch and is very durable. It saves more long term energy than it costs. It would be great if there were more natural alternatives with the same qualities.

The biggest safety concern is during the installation and immediate curing period from the outgassing of isocyantes. This may be especially problematic when the foam is applied by inexperienced operators or diy's.

You could look for trade association approved installers and applicators and stipulate in writing that the contractor follow certain trade protocols.

Here is a link that might be useful: EPA on SPF

The article the OP referenced would be more useful if the author revealed the kind of foam used and the chemicals found to be in it.

you can find a lot of info here on this site
by simply searching the site for foam insulation
posts.

not all will apply, but there are many threads
about sf insulation.

install problems usually arise from wrong mix and or temp
of product. moisture content or wood being foamed
too high. installer not trained. to list a few.

product issues like R-value of foam not meeting
code requirements, and 'average' fill of insulation
resulting in low spots in insulation 'averaged' out
by excess product. to list most common.

read through posts via site search.

best of luck.

This piece from the Green Building Advisor sums up an informed discussion on spf with loads of links.

In the discussion, Robert Riversong raises the often overlooked fact that spf helps seal in all the bad stuff in indoor air that builders then have to try to counteract with more complicated ventilation systems.

"Building Science," says Riversong, "ignores the most important thing: that homes are for human habitation. The health of the occupants (as well as the health of the environment which supports human and non-human life) must always take precedence over energy efficiency (which is now required only because of our over-reliance on science and its handmaiden, technology)."

This post was edited by worthy on Tue, Feb 5, 13 at 0:07

The reference information posted by the members here is the best way to educate yourself about insulation. Unfortunately, many internet sites and blogs are not reliable. Some are homeowners relating health problems that they assume are from one insulation or another and some are entirely fabricated. This happens because the major insulation manufacturers are locked in a fight for market share and the organizations that they pay to promote their products will stop at nothing to discourage homeowners from using the other products.

"We are in contact with 30 other families in the USA and Canada"

Out of what population exposed?

Some folks are allergic to various medications.

Should we ban those also?

The 'precautionary Principal' when misused would have us all still living in in caves.

This post was edited by brickeyee on Tue, Feb 5, 13 at 11:27

"In the discussion, Robert Riversong raises the often overlooked fact that spf helps seal in all the bad stuff in indoor air that builders then have to try to counteract with more complicated ventilation systems."

ventilation systems don't have to be complicated
or expensive.
saying that foam is 'sealing in all the bad stuff'
is an alarmist pov.

bad stuff aka chemicals are in nearly everything.
you can't blame a reaction to chemicals in carpet,
or other items on foam. outgassing takes time,
and if a homeowner is chemically sensitive then
care from the time the first part of the build
is needed.
reactions to hvac caulk, finish of wood floors
and paint the walls have to be taken into account,
and products chosen that have less impact.

even without foam some people have reactions to
materials & even equipment & furnishings of the home.

building science's motto has ALWAYS been
Build tight, VENTILATE right.

they go hand in hand.

Agreed. The computer you are sitting in front of is probably more toxic than 99.99% of spray foam jobs.

Indoor Air Quality is best served by mechanical ventilation.