Sciencemadness Discussion Board

Good Chemical Respirator for Home Labs?

AMchemistry - 15-3-2015 at 16:15

I have a home lab and recently acquired strong acids. Whats a good Chemical respiratory less than 50$?

Metacelsus - 15-3-2015 at 16:23

Most cheap respirators are actually filter masks, and only protect against particulates, not fumes. I'm not sure you can find any bona fide respirators/gas masks for under $50. You might be able to make a small fume hood for that cheap, depending on where you get parts.

Zombie - 15-3-2015 at 16:41

I have been working with strong vaporous chemicals for 43 years. Around 10 years ago I found these...

http://www.gemplers.com/product/181369/Sundstrom-Basic-Pack-...

Wholesale they cost me about 35 bucks for the kit. They take specific cartridges for your application, ie: strong acids, multi vaporous chemicals, ect...

I know you can't do better for the money.

Spray paint a 93' yacht f, that takes four 10 hour days to complete spraying, and you will appreciate what a good mask is. Multiply that times the number of years, and it's easy to grasp the fact that these masks work.



sundstrom-basic-pack-181369-lrg.jpg - 402kB

[Edited on 3-16-2015 by Zombie]

Magpie - 15-3-2015 at 19:31

Here's one by MSA I bought for use when applying epoxy paint. It uses screw on cartridges for particulates (HEPA) and chemical absorbtion, which are sold separately.




MSA ComfoClassicHalf-MaskRespirator.png - 523kB

bobm4360 - 15-3-2015 at 19:38

If you're working with acids and need a mask, consider a full-face mask. The same vapors that will damage your lungs will also damage your eyes. Safety gear ain't cheep, but it beats the alternative.
Regards,
Bob

subsecret - 16-3-2015 at 18:40

You can get various gas mask filters on Ebay and other places, most of which have NATO threads. There are many full-face gas masks to choose from.

careysub - 24-7-2015 at 10:42

I have been looking into various options for breathing protection: a filter respirator, building a fume hood, etc. and am now considering the use of a supplied air hood, like this for example:
http://www.gradeatools.com/SAS-Safety-9816-00-Supplied-Air-G...

Problems with the filter mask approach:
* You can't have a beard (like me) and get a good seal
* Filter cartridge selection (I want one solution that will protect me from anything I might take a fancy to working with)
* Cost (full face masks are pricey)
* Visibility (some masks, like the cheaper military style, don't look like they have great field-of-vision)
* Fit (can't try before I buy if I order; I can guess the correct size, but could be wrong)

Problems with a fume hood:
* I don't have a permanent work station, but must use a portable table (either on the back patio or in the garage)
* Size: a fume hood is a large structure, storing and moving around would be a major problem
* Cost: building one, with a suitably powerful blower, is not cheap

The supplied air hood on the other hand is one-size-fits-all, no seal problem, excellent visibility, protects against anything, and is relatively cheap. The model I linked to is around $50, cheaper ones are available, but I thought this one looks better. Of course I need to provide the air supply, but I don't think this will be much of a problem to rig-up. A flow rate of 3 CFM is considered "high" for this application (actual resting respiration is about 0.35 CFM), a squirrel cage blower should have no trouble providing plenty of air.

Since I would be resting and stationary when using this, being tethered to an air supply is no problem.

zed - 24-7-2015 at 13:43

I bought a respirator recently at Harbor Freight. Thirteen bucks, on sale. I bought it for allergies.

That being said, I trust no simple respirator, when my life is at stake. Those cartridges have a limited capacity to suck up gaseous Death-oleum.

A good hood is nice. Though usually at some window position, it doesn't quite cut it.

A well sealed glove box set-up is decent. Outside air, I also trust (AKA Supplied Air).

Good car painting establishments, often utilize Supplied Air, to protect their painters from noxious fumes. At least, they used to....back when paint was paint, the fumes were nasty, and manufacturers weren't very willing to identify what exact solvents you might be sucking in.

As for needing special equipment for handling strong acids. What acids? How strong? How hot? How much?

Under ordinary circumstances, in the old days, most of us didn't usually worry too much about using respirators when working with common acids.

HCl produces some vapor at STP, but we usually didn't worry about it much. Your body can easily neutralize very small amount of vapor.

H2SO4 at STP produces very little vapor. It is a high boiler.

Phosphoric Acid...Never worried about it.



[Edited on 24-7-2015 by zed]

aga - 24-7-2015 at 13:54

Quote: Originally posted by Zombie  
I have been working with strong vaporous chemicals for 43 years.

Zomb was last seen 9-7-2015 at 19:05

Could just be on holiday, but i'd wait for Zomb's re-appearance before taking the recommendation.

Magpie - 24-7-2015 at 18:17

Quote: Originally posted by zed  

A good hood is nice. Though usually at some window position, it doesn't quite cut it.


With "constant flow" design "not cutting it" will not occur. My hood has it. I have written extensively about how to get this feature on this forum.

Corrosive Joeseph - 25-7-2015 at 04:33

http://www.moldex-europe.com/en/products/full-face-masks/ser...

gatosgr - 26-7-2015 at 10:46

A decent full face mask costs 150$+++ not to mention that there is a certain volume of air you can filter before you need to change the filters. A fume hood is a better choice I have some respirator masks but I wouldn't trust them with nasty chemicals.
Quote: Originally posted by Magpie  
Quote: Originally posted by zed  

A good hood is nice. Though usually at some window position, it doesn't quite cut it.


With "constant flow" design "not cutting it" will not occur. My hood has it. I have written extensively about how to get this feature on this forum.


Where is it? I will try to build a fume hood my own but I haven't used any cad software to calculate air flow and pressures.

[Edited on 26-7-2015 by gatosgr]

Magpie - 26-7-2015 at 15:25

Quote: Originally posted by gatosgr  

Where is it? I will try to build a fume hood my own but I haven't used any cad software to calculate air flow and pressures.


Here's one good thread (among several):

http://www.sciencemadness.org/talk/viewthread.php?tid=11145

There are more pictures of my hood in the "Tour My Lab" thread.

My 15' of ducting is made from 8" ID PVC irrigation pipe.

There's one long radius 90° elbow coming off the hood ceiling, 3ea 22.5° elbows, and an outlet plenum fabricated from ss304. The blower itself provides one 90° turn to the peak vent (grill) outlet.

I estimated my pressure drop to be about 0.75" H2O using hand calculations.

My belt driven squirrel cage blower (Dayton) is rated at 450cfm @0.75" H20.

This is all quite doable with sufficient space and money. If you have any more questions please ask.


[Edited on 27-7-2015 by Magpie]

[Edited on 27-7-2015 by Magpie]

Tabun - 27-7-2015 at 06:21

Fumehood materials for fuming nitric acid?In order to be considered good,what's the concentration of gas a filter should be able to protect against?

unionised - 27-7-2015 at 08:02

A mask is what you wear if you can't work out how to control the fumes properly; it's the last resort.

macckone - 27-7-2015 at 08:08

Layered protection is best.
Use a good fume hood and/or glove box.
Then use a mask on top of that.
If you are working outside then a mask is pretty much it.
I have a beard so a mask really doesn't work well.

gatosgr - 27-7-2015 at 09:55

Looks like a nice fume hood magpie, what are the dimensions for the box? Why is the spacing of the baffle 5cm? What is the face velocity? Are these sliding windows?




If you want to measure static pressures inside the chamber you can make a u tube manometer easily using a clear tube.

http://blog.aimsedu.org/2014/08/06/a-diy-u-tube-manometer-fo...

The Volatile Chemist - 27-7-2015 at 12:25

ULINE Spraypaint Respirator, google it. I used one today at my job for cleaning things with a vat of lacquer thinner, and I couldn't smell the thinner at all with it on. They also feel like they'd last a while, and are very comfortable :) When I stop working at the job I'm at now, I'll probably get to keep the one I used today :)

Magpie - 27-7-2015 at 13:05

Quote: Originally posted by gatosgr  
Looks like a nice fume hood magpie, what are the dimensions for the box? Why is the spacing of the baffle 5cm? What is the face velocity? Are these sliding windows?


The dimensions are listed on page 1 of "Tour My Lab":

http://www.sciencemadness.org/talk/viewthread.php?tid=4777#p...

5cm is a guess based on commercial designs. Face velocity is ~ 1.0 ft/s. There is only one pane in the window, and yes, it is sliding. It is a commercial window.

gatosgr - 27-7-2015 at 13:42

I doubt if I will be able to find a descent priced sliding window where I live in.

Magpie - 28-7-2015 at 07:45

A new single hung window with a rough opening of 4 foot x 5 ft is going to cost more than a few dollars no matter where you live. What do you consider a decent price?

Often times used windows are available for cheap as listed in the classified section of newspapers.

gatosgr - 28-7-2015 at 08:06

not 400$ ?...

I have a respirator for now but it's not a good one although I didn't notice H2SO4 smell when wearing it.

[Edited on 28-7-2015 by gatosgr]

The Volatile Chemist - 29-7-2015 at 09:32

I do too, it cost $30 from ULINE, and has replaceable filters. I have no clue how much the filters cost, but they cant be too bad. Keep in mind this is just for amateur science. It doesn't have to be perfect, a respirator is supposed to be a fallback. One shouldn't let fumes just run wild any time.

gatosgr - 29-7-2015 at 11:35

Hey magpie I made the fume hood the exact same with your dimensions except I used plywood and it looks feking huge, I can literally fit in it myself.

Regular respirators don't filter poisonous gases that's why I need the fume hood otherwise I will turn the fume hood into a closet it has the right dimensions...:P




[Edited on 29-7-2015 by gatosgr]

Magpie - 29-7-2015 at 12:50

If you do organic syntheses you will use and appreciate all that space. My hood is barely tall enough for a 600mm fractionating column with reflux condenser/splitter.

gatosgr - 18-10-2018 at 11:00

Quote: Originally posted by Magpie  
If you do organic syntheses you will use and appreciate all that space. My hood is barely tall enough for a 600mm fractionating column with reflux condenser/splitter.


Sorry to dig up this old post but I will need to operate the fume hood I built some years ago according to the dimensions you posted, right now it's a plywood box and baffles coated with 2-3 coats of epoxy, the only thing that is missing is the sliding window. According to what you posted the dimensions are as follows

box face dimensions
4' x 5' = 122 x 152 cm

window dimensions
48" x 41.5"= 122 x 105 cm

so there is a 47 cm bypass at the top or am I mistaken somewhere? Thanks.