Printable View
Thanks Rob, I can believe it.
In the Melbourne lab, the individual components for Adaldite were purchased in 1 liter cans.
Rhere would be a mixing-day and the lot was subdivided and frozen.
Unfortunately, that wasn't even done in a fume hood.
The catalysis rate was set for 60C for 8+ hours in a small low temp heated oven/box.
That gave us all sorts of open working time with specimens.
I don't recall needing more than 50ml per week.
I agree with this. hot weather speeds up reaction time. When I got sick from it, the weather was hot, and there was a lot of epoxy to spread in poor joinery. ie. I was constantly around the glue up for many hours. Couldn't leave to do something else.Quote:
Originally Posted by mspil
It must be understood that ALL epoxies produce toxic fumes of some sort in the curing process.
Some are worse than others...some very much worse.
The real problem is that the results may not be immediate or particularly intense.
All epoxies should be used in very well ventilated areas ( moving air) when used in volume...like a big fan at your back.
If you are mixing a spot of epoxy on the back of a matchbox, its hardly going to be a serious incident.
but if you mixed up half a litre of the same epoxy and spread it about...there will be lots of fumes evolved.
The MSDS will never give you the full picture. and mostly downplay the hazards...yeh I know.
Problems that can come from epoxy include
.
Asthmatic like reactions
skin rashes
twiches....particularly in the face
dull nausia
dull to pronounced headaches
a vague but presistent feeling of being unwell...chronic fatigue.
All the above may not appear straight away..may take hours or days to develop after exposure.
AND they may persist for very long times days, weeks or even months.
then there are the long term effects.
long term sensitisation....and not just to epoxy...exposure to epoxy can make you sensitive to all sort of chemicals...or mess with your immune system and make normal elergic reactions worse or where you did not have them before.
With long term exposure and cetain epoxies promotion of cancer, respiratory and circulatory problems and messing with your DNA.
Many of the modern epoxies are far and away better than those of the past......but they all deserve respect.
If typical normal solvents are equated to a bloke who will walk up to you and smack you straight in the face.
Epoxy is the bloke who will sneak into your room at night while you are asleap and poke you with a rusty pin every night for a year.
cheers
I think that what got to me, using Araldite (apollogy's for the speeling), was the occasional (?) skin contact that was not
cleaned off immediately. I don't think that "fumes" were the issue but they might have been.
The 60C curing oven sat in a fume hood which was never shut off.
But, we mucked with the stuff, daily, on the bench. Beakers of it.
Just assume that all epoxies in all their mixed formula glories are really nasty short.
The silence of manufacturers proves dick-twiddly.
It isn't water or wine or whiskey.
Both fumes and skin contact can cause reactions and toxin transfer.
BTW..and this is standard polocy with epoxy.
if you get it on your skin..it is not recommended to use solvents to get it off.
The recommendation is acid :o......vinegar or citric.
There are several citrus bassed hand cleaners that work pretty damn well on uncured epoxy..and a number of other things BTW.
Setone citri-scrub is what I keep these days.
typical solvents will actually mobilise the toxins and allow them to transfeer across the skin barrier far more easily.
gloves, long sleves, and long trousers are recommended.
A mate went and did some eboxy work on a little stich and glue boat.....I warned him.....told him the brand of epoxy to use..warned him to cover up.....but did he listen.....
Anyway..he worked with tis stuff an hour or so for about 3 days running.....a couple od day later his legs broke out in this rash...that only started to fade after about 2 months.......I told ye...I told ye.
cheers
soundman: reads that safety considerations have made positive progress in the 40+ years since I puddled around with Araldite.
It is the embedding medium of choice for biological specimen sectionsto be examined in an electron microscope.
About all we knew at the time was that very fair-skinned users were far more sensitive than workers with typical dark, African skin colors.