Chemicals of "Concern" Found in Philips Breathing Machines | Hacker News Reader

Chemicals of "Concern" Found in Philips Breathing Machines

propublica.org

56 pointsJimmc41413 comments

From an engineering perspective don't you have to assume the worst case scenario when you use materials that might be inhaled? Is there any reasonable argument for using formaldehyde here or is it just because of cost?

It really seems like some decision makers should be going to prison here

None of this stuff should be able to make it into the air circuit. This sounds like really shoddy design by respironics. Adding noise insulation to the machine makes total sense, but the machine should suck in air from the outside, pass through a filter, and then blow out a tube. It makes zero sense for there to be a way for that air to mix with the insulation foam.

Quick rant on PAP noise: the machines are actually pretty quiet most of the time. They tend to get noisy when fan has to make drastic changes in speed, such as on exhale if pressure relief (EPR, or C-Flex in respironics) is enabled. If noise is an issue, turning off EPR can make a huge difference.

Is the internal system claimed to be 'air tight'? Because the default assumption for practically everything in this world is that air will penetrate at all angles.

In practice it clearly isn't airtight, otherwise the foam wouldn't have been able to end up inside patients. Not sure whether it would have been easier to design an airtight circui, or to ensure that the insulation is wrapped in something that effectively separates it from the air circuit.

Either way, this is pretty shitty. These machines are pretty expensive (and someone makes a hefty profit on them, because most patients rent theirs). Seems like the least they could have done was make sure it was worth the money.

Oh, great, I just got my replacement machine a few months back.

Formaldehyde.

Nothing on concentrations or anything, which makes it difficult to assess the risk level, compared to e.g. a cheap bed made out of particleboard and foam mattresses. Meh.

Not just formaldehyde fumes, BTW:

"In announcing a massive recall of ventilators and sleep apnea machines, Philips Respironics acknowledged that an industrial foam placed inside the devices to reduce noise could break apart and send tiny particles and fumes into the noses, mouths and lungs of patients."

https://www.propublica.org/article/nine-stories-of-people-im...

That was the original polyurethane foam, this article talks about its replacement.

Still, sucks for the affected. I just got my CPAP machine and if I had to choose between cancer or constant sleep deprivation, I'm not sure which way I'd go.

Easy: get a resmed machine. They're better than the respironics machines in every possible way.

Happily mine is a ResMed so I don't need to make that choice.

This is not surprising, actually.

Plenty of non-PU foams use formaldehyde based resins - melamine-formaldehyde foam is an example.

The article states "[WHO threshold proposed by Philips] allows for far higher formaldehyde emissions than benchmarks used by other organizations, including the Environmental Protection Agency."

The WHO threshold is, based on quick googling, 0.08 ppm which sounds pretty reasonable. I have been unable to find a corresponding EPA value. Anyone got better luck?

I can't find anything on foam either, just the resin in wood products:

- https://www.epa.gov/formaldehyde/laws-and-regulations-concer...

- https://www.regulations.gov/document/EPA-HQ-OPPT-2016-0461-0... ("Formaldehyde Emission Standards for Composite Wood Products", linked from the first page, this one has ppmz)

- https://www.cpsc.gov/safety-education/safety-guides/home/upd... ("An update on formaldehyde", lists some numbers like 0.1 ppm for absolute upper limit without adverse effects for most people, 0.03 ppm in low-emission environments)

Reply on news.ycombinator.com