MC1992

Hi again science forums! Me again, back with a bit more material related question. As someone with near zero background in chemistry, I want to know if polyurethane ( sometimes referred to as PU) foam is safe? My preliminary readings and research shows that a residue called " isocyanates" left over by the processing of polyurethane foam, among others, could be quite problematic. There are articles on the internet suggests that it is best not to use mattresses with polyurethane foam as the stuffing. Again, I want to know what people who specializes in this or have received higher education in chemistry think of this?

Really! . Wasn't most tin cans chemically inert to begin with? Oh well, come to think of it, there does appear to be a layer of paint of some sort covering the inner wall. I always thought the "tin can iron" is a special kind of iron - it comes with a "natural" varnish after processing.

Really? Never thought of it that way. I guess it's alright then.

Hah, thanks a lot, and again, I'm arriving at the philosophical quandary of weighting costs against benefits. So... in theory, from a more probabilistic point of view, I don't have to worry about the particles it leaches into the air, right? And it does leech stuff into the air, just in minuscule quantity, no?

Ah, it's actually sufficiently informative really. But if I may: How toxic is this paint/coating typically? I know this question is super broad, but should I be worried about it? It's a bed with bedframe coated in it... made by IKEA. I mean when I get it clearly would already be... cured/solidified? I haven't purchased it yet. I want to know as much as possible about what I'm getting into.

I am quite interested in knowing what kind of chemicals they use to coat metallic furniture, usually referred to as "Epoxy". As far as I know, there could be several varieties of combinations, anybody can provide some insight? Peace.

Goody you are so right. Back in the days the republicans and Jeffersonian idealists were as fanatical as they could be, and they were just as hotheaded. Remember John Brown? Also back in the good old Arkansas (was there an Arkansas back then?) abolitionists wouldn't just punch some slavery supporter in the jaw, they would outright shoot him to death. The Antifas are edgy teenagers proudly produced en mass by American style permissive parenting.

That's a very constructive piece of advice, thank you for the input. I will try to integrate this idea into the product design.

Thank you very much for your input. What you mentioned is a legit problem, because we haven't decided which type of LED/LEDs we will be using, the logistics and sourcing can be a tricky business, I'm looking for the general direction at this ponit.

Hello, I'm sorry if I didn't word the title better. Summary: I'm trying to detect sunlight while the LED luminaires are present and turned on. I know it may sound kind of strange but this is the idea: say you have a lounge. The LED ceiling light is on, and at the same time, natural light is coming from outside through the window. And the natural sunlight is sufficient, thus the LED lighting clearly is a waste of energy and one more reason to increase carbon emission. But often times people are too busy with themselves to care about this. You just finished an important meeting and are thinking about something really stressful, no one would notice the light is on, esp. when the room is already fully lit by natural sunlight. Now imagine 100 office buildings with 1000 such lounges over a year, the waste could be significant. So is it possible to detect certain section of the spectrum of natural sunlight, the section where it is strongly correlated with sunlight, but almost non-existent in the lights emitted by WHITE LEDs? I know most people probably would immediately think of infrared, problem is, this may not be the easiest direction since there may be extra heat source in the room, for example, a boiling coffee pot or a freezer. Also I wish the solution could be relatively affordable, so I'm guess I may have to stick with infrared/ultraviolet, however difficult. Because anything beyond is either exponentially more difficult to detect or simply too pricey. Last but not least, you can not temporarily turn off the LEDs themselves, it'll take another thread to explain why that is not an option, so I'll just simply put it here: that is not a viable solution, due to some reasons.