Hey you guys- I have been shaping a few boards out of #2 EPS from Sfoam. I have noticed a “sweet” smell in the air when shaping the stuff, and it seems to be causing nausea. I switched over to wearing my respirator with carbon filters, instead of my normal dust mask, and that seems to have fixed the problem. What’s up? Am I just imagining things? Thanks, -Carl
Yup, it’s probably the blowing agent for the EPS. However, there should not really be that much of it although some would probably be released during shaping. I’ve only had that smell after glassing, so I actually used to think it was the epoxy. I guess the heat from the epoxy going off causes the EPS to release some.
Good idea with the mask and some ventilation, specially for a production shaper I would imagine. Also, I would check with the supplier because given some time I would imagine most of the pentane being gone from the blank. Maybe there is something wrong with the EPS.
Here’s a link to pentane emissions in standard and low pentane EPS.
Check out the corporate logo in the background.
I’d rather breath the co2 version, personally speaking. That’s as safe as drinking a soda. Maybe the foam blank manufacturers can pay attention to this detail since their foam is being hand “sculpted”.
At the moment, I think all EPS uses pentane as a blowing agent. I put a list of EPS resin suppliers on another post and didn’t find any that offer anything but pentane systems. Do you have any more info?
There is one company that is experimenting with water blown EPS, but I don’t think it’s in the market yet.
As far as smell, pentane is the safe bet. Takes a long time for pentane to fully leave EPS and all EPS is not created equal.
I have discussed the environmental factors with the EPS manufacturer here in Montreal, in fact he mentioned it when we first talked and I told him the most blanks were made with PU foam. He said that that foam is fairly toxic where as the EPS his company makes uses CO2 as a blowing agent.
I guess you should make sure of what the foam you’re using has in it, and protect yourself accordingly.
From the data below, pentane doesn’t seem to be not particularly toxic, but it is a central nervous system depressant. If you’re feeling effects in a confined space, an organic vapor respirator or better ventilation in the shaping bay is probably a good idea.
Probably must less of a concern than styrene is during polyester glassing, but hey better safe than sorry.
Edit: Just to be clear, I put styrene (the main thing you smell with polyester resins) here for a comparison only. EPS is not going to release styrene.
Not at all my area of expertise, but after reading those links, it looks like the threshhold in order to smell the stuff is 2-10 parts per million (ppm). The NIOSH recommended 10 hour (weighted avg) exposure limit is 120ppm. So if there’s possibly 10 ppm in your air, and you’re working in there 8 hours, perhaps you’re getting close to the recommended limit? It seems to me a reasonable idea to wear a respirator, particularly if its making you nauseous.
Might also want some fresh air into your shaping area, particularly if (as PlusOne suggests) it smells sweet when you first come in the room… even if its not a particularly bad one, it’s still listed as a neurotoxin.
(PS i own 3 respirators, so you can tell where I come out on these kinds of questions…)
the eps guys i get mine stuff from told me they let there huge cubes sit a for weeks before they hotwire them and told me the longer i wait to cut the better. they also said after i cut to let them sit around for awhile before using them… i bet this has something to do with why.