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electromagneticpulse
2005-Feb-26, 02:13 AM
I was wondering if HCl or HF is capable of reacting/breaking down your average household plastic, like the ones they use for vacuum cleaner pipes.

Thanks :)

Grey
2005-Feb-26, 02:30 AM
I was wondering if HCl or HF is capable of reacting/breaking down your average household plastic, like the ones they use for vacuum cleaner pipes.

Thanks :)
Um. Why do you want to know? 8-[

jfribrg
2005-Feb-26, 04:13 AM
Maybe he spilled some on his carpet and doesnt want to ruin the vacuum. In that case, pour some baking soda on it first and then vacuum.

electromagneticpulse
2005-Feb-26, 04:45 AM
I don't know anywhere where you can get HF around here. HCl isn't that hard but i dont have the money to buy any... and i'm not planning on making any.

It was just a general wondering.

Jpax2003
2005-Feb-26, 05:31 AM
Hydroflouric acid is used to etch glass, so no storage in silicate bearing materials. IIRC, HF is stored in Teflon containers, but this link (http://www.camd.lsu.edu/msds/h/hydrofluoric_acid.htm) claims it is ok in polyethylene. I think Hydrochloric acid can besafely stored in PVC containers per this link (http://www.science-education.org/classroom_activities/chlorine_compound/hcl.html).

Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)

A fatal accident occurred in a laboratory in Australia in 1995, resulting in the death of a technician. The technician was seated when he knocked over a small quantity (between 100 and 230 ml) of hydrofluoric acid (HF) onto his lap, splashing both thighs

The technician sustained burns to 9% of his body, despite washing his legs with water at 6 liters/min. No calcium gluconate gel was applied to the affected area and contaminated clothing was not removed during the flushing with water. His right leg was amputated 7 days after the incident. He subsequently died from multi-organ failure 15 days after the hydrofluoric acid spill.

A Thousand Pardons
2005-Feb-26, 08:36 AM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?

Jpax2003
2005-Feb-26, 08:46 AM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?same site as above

SKIN CONTACT/SAFETY SHOWER
Spills of HF shall be flushed for a maximum of 5 minutes. This chemical is so aggressive in its attack on skin and bone that the most important response is to apply a calcium gluconate gel antidote as soon as possible. Remove contaminated clothing immediately (wear manufacturer recommended protective gloves when handling contaminated clothing). After 5 minutes in the safety shower, treatment of the skin with calcium gluconate gel should be initiated and continued, using manufacturer recommended gloved hands, while awaiting medical emergency treatment. White specks appearing around the contaminated area indicate that the desired reaction has taken place. (If cloudiness or separation occurs, then the gel must be re-applied.)

frogesque
2005-Feb-26, 10:18 AM
Safety (MDS) data: Hydrofluoric acid (http://physchem.ox.ac.uk/MSDS/HY/hydrofluoric_acid.html)


Note: this chemical is extremely hazardous. Do not use without taking professional advice


Ingestion, fume inhalation or skin contact can be fatal. This is not a jokeshop chemical

spillkitonline.com: HYDROFLUORIC ACID CASRN: 7664-39-3
(http://www.spillkitonline.com/shop/xcart/customer/hydrofluoric_acid_casrn.htm)

Not really funny but definately one of those "Oh!..Fluff!!" moments:


A student was attempting to prepare anhydrous hydrogen fluoride by dehydrating aqueous 60% hydrogen fluoride solution with concn sulfuric acid. Addition of 200 mL of sulfuric acid to 500 mL of hydrofluoric acid in a 1 L copper flask led to a rumbling noise, then a fountain from the flask neck of hot mixed acids which severely corroded the window glass and the floor tiles.
[Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990 1218]**PEER REVIEWED**
#-o

And if all that's not enough to put anyone off here's the case study of the incident reffered to by Jpax2003 above: Safety Line Institute, Australia: Lecture (http://www.safetyline.wa.gov.au/institute/level2/course16/lecture76/l76_01.asp)


...
CALCIUM GLUCONATE WAS NOT AVAILABLE

The technician sustained burns to 9% of his body surface area, despite washing his legs with water from a makeshift plumbing arrangement that supplied water at 6 litres per minute. No calcium gluconate gel was applied to the affected area (this gel is an effective topical treatment for hydrofluoric acid burns) and contaminated clothing was not removed during the flushing with water. Following flushing, the technician, who appeared to be in severe pain and shock, immersed himself in a chlorinated swimming pool at the rear of the workplace, where he remained for approximately 35-40 min before ambulance help arrived.

HE DIED FROM MULTI-ORGAN FAILURE 15 DAYS LATER

...


This was caused by a small quantity (100-230 ml) of HF

Edit: corrected reference to HF, not HFl as in the original

electromagneticpulse
2005-Feb-26, 03:47 PM
IIRC i read that 10% exposure to HF was normally fatal even with proper medical attention. I'm definitely not going to be playing around with any.

I remember we had some in school but it was sealed in a compartment in a vacuum cupboard, it seemed a bit over the top at the time but it was in a 1-litre flask. Makes sense now though.

dgruss23
2005-Feb-26, 03:55 PM
An episode of ER was based upon that. A firefighter (I think) had HF spilled on him - which proceded to scavenge the calcium in his body.

dgruss23
2005-Feb-26, 03:57 PM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?

Definitely not. I heard about one local teacher that accidentally bumped a large bottle of concentrated HCl on the corner of a lab bench. It shattered and spilled all over his pants. He immediately went to the safety shower and stripped his pants - with the students still in the room.

Zachary
2005-Feb-26, 04:15 PM
Safety (MDS) data: Hydrofluoric acid (http://physchem.ox.ac.uk/MSDS/HY/hydrofluoric_acid.html)


Note: this chemical is extremely hazardous. Do not use without taking professional advice


Ingestion, fume inhalation or skin contact can be fatal. This is not a jokeshop chemical

spillkitonline.com: HYDROFLUORIC ACID CASRN: 7664-39-3
(http://www.spillkitonline.com/shop/xcart/customer/hydrofluoric_acid_casrn.htm)

Not really funny but definately one of those "Oh!..Fluff!!" moments:


A student was attempting to prepare anhydrous hydrogen fluoride by dehydrating aqueous 60% hydrogen fluoride solution with concn sulfuric acid. Addition of 200 mL of sulfuric acid to 500 mL of hydrofluoric acid in a 1 L copper flask led to a rumbling noise, then a fountain from the flask neck of hot mixed acids which severely corroded the window glass and the floor tiles.
[Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990 1218]**PEER REVIEWED**
#-o

And if all that's not enough to put anyone off here's the case study of the incident reffered to by Jpax2003 above: Safety Line Institute, Australia: Lecture (http://www.safetyline.wa.gov.au/institute/level2/course16/lecture76/l76_01.asp)


...
CALCIUM GLUCONATE WAS NOT AVAILABLE

The technician sustained burns to 9% of his body surface area, despite washing his legs with water from a makeshift plumbing arrangement that supplied water at 6 litres per minute. No calcium gluconate gel was applied to the affected area (this gel is an effective topical treatment for hydrofluoric acid burns) and contaminated clothing was not removed during the flushing with water. Following flushing, the technician, who appeared to be in severe pain and shock, immersed himself in a chlorinated swimming pool at the rear of the workplace, where he remained for approximately 35-40 min before ambulance help arrived.

HE DIED FROM MULTI-ORGAN FAILURE 15 DAYS LATER

...


This was caused by a small quantity (100-230 ml) of HFl

:o Oh dude, they never told us that when we dabbled in the stuff on a visit to Imperial College :-s . I knew it was nasty stuff, but still...

W.F. Tomba
2005-Feb-26, 04:36 PM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?

Definitely not. I heard about one local teacher that accidentally bumped a large bottle of concentrated HCl on the corner of a lab bench. It shattered and spilled all over his pants. He immediately went to the safety shower and stripped his pants - with the students still in the room.
It's standard procedure to remove the clothing. I know that's what you were saying, dgruss, but I'm not sure whether ATP was asking about removing the clothing or not removing it.

(I hope I'm not being annoying. I like to make things clear.)

dgruss23
2005-Feb-26, 04:41 PM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?

Definitely not. I heard about one local teacher that accidentally bumped a large bottle of concentrated HCl on the corner of a lab bench. It shattered and spilled all over his pants. He immediately went to the safety shower and stripped his pants - with the students still in the room.
It's standard procedure to remove the clothing. I know that's what you were saying, dgruss, but I'm not sure whether ATP was asking about removing the clothing or not removing it.

(I hope I'm not being annoying. I like to make things clear.)

No - that's fine. You're right to clarify. I seem to be having an issue with sufficient clarity the last 24 hours. Could be that I'm distracted because my wife's been down with the flu the last 3 days. :(

Normandy6644
2005-Feb-26, 05:42 PM
Doesn't it depend on the molarity of the acid? IIRC (going back to high school here) you could spill HCl that was highly diluted and still be okay.

papageno
2005-Feb-26, 05:44 PM
Doesn't it depend on the molarity of the acid? IIRC (going back to high school here) you could spill HCl that was highly diluted and still be okay.
I thought that HCl is what we have in our stomachs.

electromagneticpulse
2005-Feb-26, 06:18 PM
Doesn't it depend on the molarity of the acid? IIRC (going back to high school here) you could spill HCl that was highly diluted and still be okay.
I thought that HCl is what we have in our stomachs.

Our stomachs have natural protection against it, they have mucus secreting glands that line the stomach so the acid doesn't digest the stomach. But the HCl used in schools, which is extremely dilute, only gives a mild irritation to the skin (Experiance first hand, literally).

Tbutyl
2005-Feb-26, 11:21 PM
Use extreme caution with HF... read this link (http://www.ehs.washington.edu/Updates/tipsHFAcid.htm)


::snip::
contaminated clothing was not removed during the flushing with water.
Is that standard proccedure?

Definitely not. I heard about one local teacher that accidentally bumped a large bottle of concentrated HCl on the corner of a lab bench. It shattered and spilled all over his pants. He immediately went to the safety shower and stripped his pants - with the students still in the room.
It's standard procedure to remove the clothing. I know that's what you were saying, dgruss, but I'm not sure whether ATP was asking about removing the clothing or not removing it.

(I hope I'm not being annoying. I like to make things clear.)

Because chemistry lab safety is so important, I would like to reiterate along with others that it is standard procedure to remove contaminated clothing before rinsing with water.
The reason for removing clothing is two fold;

1) By removing the contaminated clothing, you are also getting much of the contaminant away from your skin.

2) Many chemicals can react with the water to make things worse. One common example is concentrated sulfuric acid (which is found in most undergraduate chemsitry labs). If you were to spill concentrated sulfuric acid on yourself, then step under the safety shower, the mixing of the water with the sulfuric acid in your clothing results in a very exothermic reaction which would cause an even worse burn. (Remember, never add water to acid, always follow the old saying, “do as you oughter add acid to water”).

jnik
2005-Feb-27, 02:40 AM
In high school chem class we kept 6mol HCl in plastic containers with no problem. Never touched HF.

(*did* spill 6mol nitric acid on my hand...didn't hurt much, but turned yellow for a week).

Jpax2003
2005-Feb-27, 06:42 AM
BTW, prevention is better and easier with acids, and really any chemistry. Wear an appropriate apron and gloves, goggles or mask or whatever is called for.

dgruss23
2005-Feb-27, 02:46 PM
Doesn't it depend on the molarity of the acid? IIRC (going back to high school here) you could spill HCl that was highly diluted and still be okay.
I thought that HCl is what we have in our stomachs.

Our stomachs have natural protection against it, they have mucus secreting glands that line the stomach so the acid doesn't digest the stomach. But the HCl used in schools, which is extremely dilute, only gives a mild irritation to the skin (Experiance first hand, literally).

Yes, most of the time the HCl the students use in high school is highly diluted ... but that's because the teachers have the concentrated stuff that could cause serious burns stored away in a cabinet where students cannot get access. When we prepare the stuff for student use we put on the gloves, splash goggles, aprons and dilute it to 3 molar or less (usually 1 molar or less).

Grey
2005-Feb-27, 03:55 PM
My mother tells a story about doing something when she was young that she knew better than to do, but didn't think through the chemistry clearly. She was cleaning their wooden porch, which was badly in need of it, and thinking that she needed something really strong she put both ammonia and bleach into the water. After scrubbing for a while, she noticed that her hands were really stinging. It sure got the porch clean, though! :-?

Tbutyl
2005-Feb-27, 06:37 PM
My mother tells a story about doing something when she was young that she knew better than to do, but didn't think through the chemistry clearly. She was cleaning their wooden porch, which was badly in need of it, and thinking that she needed something really strong she put both ammonia and bleach into the water. After scrubbing for a while, she noticed that her hands were really stinging. It sure got the porch clean, though! :-?


Your mother was very fortunate that she was cleaning in an open space when she mixed ammonia with bleach or the results could have been much worse than just stinging hands. The mixing of bleach with ammonia leads to the production of chloramines which can do nasty things to your respiratory system. For more info on why one should never mix acids or ammonia with bleach see:

http://www.cdc.gov/mmwr/preview/mmwrhtml/00015111.htm

electromagneticpulse
2005-Feb-27, 06:50 PM
My mother tells a story about doing something when she was young that she knew better than to do, but didn't think through the chemistry clearly. She was cleaning their wooden porch, which was badly in need of it, and thinking that she needed something really strong she put both ammonia and bleach into the water. After scrubbing for a while, she noticed that her hands were really stinging. It sure got the porch clean, though! :-?

Well i had to do a COSHH course in college and the tutor told a story about one of her previous co-workers. They put high percentage bleach down the toilet and another chemical, which i forget but was something like dettol. They put the lid down on the toilet and left it and they were working with the sinks, first the chemicals shouldn't have been mixed and if they were they should have been diluted highly and disposed of (eg flushed). But that didn't happen and 5 minutes later the toilet exploded.

Now i wouldn't have wanted to be going to the toilet on that toilet :o but luckily it was only a flimsy plastic toilet so it cracked and fell apart instead of going off like a small charge. Funnily it was her only ever male employee :roll:

Grey
2005-Feb-27, 08:01 PM
Your mother was very fortunate that she was cleaning in an open space when she mixed ammonia with bleach or the results could have been much worse than just stinging hands.
Yup. Also fortunate that it involved relatively small amounts mixed in water so the resulting solution was fairly dilute. She realized after the fact just what she had done and that she should have known better. :-?

TriangleMan
2005-Feb-28, 11:59 AM
When I look back at all of the chemicals I used during chem lab in college I'm amazed I got through unscathed. Pure chlorine gas, DMSO, concentrated acids . . . safety was drilled into our heads every class.

A friend of mine spilled phosphoric acid on his pants and didn't go to the shower since he wasn't feeling anything -- until 2 minutes later. Too late to prevent some burns. [-X

Swift
2005-Mar-01, 04:04 AM
Because chemistry lab safety is so important, I would like to reiterate along with others that it is standard procedure to remove contaminated clothing before rinsing with water.
The reason for removing clothing is two fold;

1) By removing the contaminated clothing, you are also getting much of the contaminant away from your skin.

2) Many chemicals can react with the water to make things worse. One common example is concentrated sulfuric acid (which is found in most undergraduate chemsitry labs). If you were to spill concentrated sulfuric acid on yourself, then step under the safety shower, the mixing of the water with the sulfuric acid in your clothing results in a very exothermic reaction which would cause an even worse burn. (Remember, never add water to acid, always follow the old saying, “do as you oughter add acid to water”).
Tbutyl, I found your point # 2 a little confusing, so I want to clarify. Yes, adding water to acid can be dangerous, particularly if it is concentrated acid and a very tiny amount of water, because of the exothermic nature of the heat of disolution of the acid. But that really has nothing to do with removing clothing and may give someone the impression not to use water on acid burns. Your point # 1 was correct.

ALL ACIDS BURNS SHOULD BE FLUSHED WITH LARGE QUANTITIES OF WATER! (yes I'm shouting). The best measure is to get the person to the safety shower and strip them while you flush them off.

I'll also repeat a couple of things said already. Concentration of the acid does have a lot to do with the danger. But even dilute acid should be used with respect. The best safety measure is to wear protective clothing to prevent contact - gloves, lab coat, safety glasses.

HF is extremely nasty stuff (this is said from personal experience of use, but I've near been exposed). In industrial environments in the US you often go through special training on HF specifically to work with it.

As far as the originial question, plastic containers are generally good with acids. Teflon and polyethylene are both used for HF. But I won't use a vacuum hose :-? [-X

captain swoop
2005-Mar-01, 11:45 AM
There was a problem a few years ago with car engine fires. Some of the synthetics used in seals, hoses, plug leads etc break down and release HF when they are subject to intense heat. After the fire there is a sticky residue that contains HF.

Tbutyl
2005-Mar-01, 01:03 PM
Because chemistry lab safety is so important, I would like to reiterate along with others that it is standard procedure to remove contaminated clothing before rinsing with water.
The reason for removing clothing is two fold;

1) By removing the contaminated clothing, you are also getting much of the contaminant away from your skin.

2) Many chemicals can react with the water to make things worse. One common example is concentrated sulfuric acid (which is found in most undergraduate chemsitry labs). If you were to spill concentrated sulfuric acid on yourself, then step under the safety shower, the mixing of the water with the sulfuric acid in your clothing results in a very exothermic reaction which would cause an even worse burn. (Remember, never add water to acid, always follow the old saying, “do as you oughter add acid to water”).
Tbutyl, I found your point # 2 a little confusing, so I want to clarify. Yes, adding water to acid can be dangerous, particularly if it is concentrated acid and a very tiny amount of water, because of the exothermic nature of the heat of disolution of the acid. But that really has nothing to do with removing clothing and may give someone the impression not to use water on acid burns. Your point # 1 was correct.

ALL ACIDS BURNS SHOULD BE FLUSHED WITH LARGE QUANTITIES OF WATER! (yes I'm shouting). The best measure is to get the person to the safety shower and strip them while you flush them off.



I did not mean to infer that one should not rinse acid burns with water. Thank you for clarifying that point. However, whether one should remove clothing as they are rinsing in the shower or prior to entering the shower I think depends on the quantity of the acid involved. If a considerable amount of acid has been absorbed by the clothing such as may be the case if one spills a container full on themselves, then I believe that the clothes should be removed prior to entering the shower. I do not mean leisurely removing the clothes but rather strip darn quick and get into the shower immediately.

teddyv
2005-Mar-01, 03:49 PM
I was wondering if HCl or HF is capable of reacting/breaking down your average household plastic, like the ones they use for vacuum cleaner pipes.

Thanks :)

HCl is sold in paint stores as Muriatic Acid and usually comes in plastic bottles. We use HF occasionally for dip measurements when diamond drilling etching a glass tube) , but that is a rather obsolete method now.