(06-26-2021, 11:37 AM)SarcasticDave94 Wrote:

"It would sound like the foam is in the path of the airflow in these Respironics.

Don't accept a Respironics.

ResMed isn't identical in this foam issues and isn't affected like 

Respironics."

Quote:

Philips machines have a design flaw in how the airflow circulates around (and through) the sound-isolating foam, and in the composition of the foam itself with the use of a chemical that is known to be cancer causing, and in that foam's lack of long-term composition strength that allows it to degrade over time - accelerated by the use of advanced internal machine cleaning products such as ozone cleaners.

(06-25-2021, 05:42 PM)Guilhermedico Wrote: Indeed. I, for one, would not let the manufacturers of these ozone-generating devices off the hook in this Philips-Respironics PAP device foam outgassing recall fiasco.  I started using a new generic ozone-generating "CPAP Cleaner"  ... the mask cushion and the forehead protective piece ... turned a bright yellow color.

The discoloration may be a useful piece of evidence in some future class action, as to the effect of some ozone-generators on plastic polymers, if not on the sound insulating polymer foam in question.

(06-26-2021, 12:04 PM)WakeUpTime Wrote: On another note, it could be just a coincidence, but several days after registering my mobile phone number at the Philips Recall site, I'm getting many almost daily telemarketing (phishing) calls on that number.  I've used that number for years and never had that before.  Likely just a coincidence, but I thought I'd see if it happened to any others.  No doubt those database entries will be copied repeatedly and sent to other Philips departments and perhaps even outside Philips.

(06-26-2021, 12:31 PM)glenlyon602 Wrote: 1. What is the USA market share in a normal year for Philips vs. its competitors?

Quote:

"According to the survey, Philips Respironics currently has 62.8% of the flow generator market. 

(ResMed is the next biggest player with a 32.2% share of the market.)"

[HME Survey, 2019 Year End]

(06-25-2021, 04:35 PM)b.e.wilson Wrote: I'm a chemist, and have been looking at the chemistry of the polyester-based polyurethane foam degradation process. I haven't found anything authoritative yet, but there are two degradation pathways, one by water, one by fungus, both resulting in the same degradation products. The product that is a gas would be isocyanic acid, HNCO, H-N=C=O. It is a poison, more acidic than vinegar, reacts with amino acids, so it is a danger to the lungs. It's present in smog and cigarette smoke. In dry and cool environments, in the dark, the foam is stable.

Here's the odd thing: if there is enough humidity around to cause the degradation, the isocyanic acid will remain soluble in the water. I think it's the heat part that is important, because hot water would lower the solubility of the acid and drive it back into the air. So the combination of very high humidity then a cycle of heat would be needed. I suppose that could happen if the machine is used at night in a non-air-conditioned space, then sits during the hot day.

Or give it ozone. That stuff reacts with everything. You'll recognize the smell of ozone easily; it's the smell of a kitchen motor (the kind that makes sparks in the back) or a Xerox machine.

I think there might be some small possibility that phenyl-isocyanate could be the gas, but I'd want to see some headspace analysis of the foam first.