Sciencemadness Discussion Board - Safety Tips for n00bs/kw3ls

Safety Tips for n00bs/kw3ls

mewrox99 - 25-5-2011 at 03:07

I'm surprised sciencemadness doesn't have a thread about safety, so I decided to start one. Please post your advice

Here are my tips/warnings which everyone ought to know.

BASIC SAFETY EQUIPMENT

No lab should be without these:

Safety googles - Most important piece of safety equipment. Anyone who doesn't have a good pair (or couple) in their lab is an idiot

Gloves - Some people don't bother using gloves with chemicals. But that doesn't mean it's safe. Always keep a good box of nitrile and some solid neoprene gloves

MSDS Sheets

Bucket of water or better yet a sink.

Storage

Store chemicals that may react with each other separately.

I store organics, ionic salts, bases together and separate strong acids and oxidants

That is ok but not ideal. Bases can react with some organics in an undesirable way i.e Nitromethane and NaOH but this isn't a problem for me. Always check the incompatibilities section of MSDS sheets

STUDY FIRST

When ever you try an experiment, make sure you can find a good reference from a proper source. I.e NOT a kid on youtube.

Also take a good look at the reaction. If something doesn't seem right, do not proceed until further research.

Make sure you write up a risk analysis sheet before trying. It may seem over the top, but it's a good practice

Toxic Gases

As the name implies, toxic gases are toxic!. Work outside when toxic gases can be released. A respirator is also good when very toxic gases are in use

Randomly mixing chemicals

There has been some interesting results from certain novel energetic mixtures. But this can be dangerous. First write up what you expect to happen (in terms of chemistry), google a reference, ASK on SM to see if anyone has tried it.

Then try it in no more than 50mg amounts. Really there is no mixture I can think off (Not even KClO3/RP) that is a high risk if carefully mixed in such a quantity. ALWAYS TREAT AN UNKNOWN MIXTURE AS SOMETHING OF EXTREME RISK.

Keep Notes

Not a safety think per se, but make sure you keep a dated log of what you have done and what chemicals you have used and have the risk assessment also with it

Now I admit that I have not always followed these tips, but I was foolish and a bit of sloppy chemist, that doesn't affect the validity of these tips. A good chemist should follow these

hissingnoise - 25-5-2011 at 04:14

There's a surfeit of threads on safety here; you obviously haven't really looked . . .

Jor - 25-5-2011 at 04:22

And gloves are not essential! I rather don't have them on with acids like HCl or other mild corrosives. If you have a drop on you can reacts immediately as you feel it.

I only wear gloves when handling conc. H2SO4 in larger than mL amounts, strongly poisonous substances (cyanide), chronic poisons (lead, mercury), bromine and sensitizers (like Pt and Cr compounds).
I use thin vinyl gloves. They are resistant to most acids, mine even keep bromine outside for long enough so I can take of my glove.

And I think a fume hood, altohugh not many have them, is the single best acquirement you can get in your lab. It makess everything so much safer and you don't have to worry about dodging vapours. Just put some work in it, even a basic one is great help.

[Edited on 25-5-2011 by Jor]

mewrox99 - 25-5-2011 at 04:22

I've seen threads on specific aspects of safety, but not a general thread on safety.

@Jor: I agree gloves aren't essential for everything and you can get away with spilling a small amount of dil. HCl on your self. But every lab should have a pair gloves

[Edited on 25-5-2011 by mewrox99]

Jor - 25-5-2011 at 04:38

There are no specific threads on safety as any member here regards dangers differently and it would only give arguments. E.g some people think a hood is essential, some don't. Some member here wear full safety gear while working with dilute acids and some basic metal salts, some people work with sulfur trioxide and highly toxic compounds in large amounts without a fume hood. it's personal opinion (ofcourse within limits). You work on your own most of the time, so you have to decide what you find appropriate. Ofcourse there is some basic safety gear everyone has to have. There are no rules on what you need to have, however you can provide guidelines, but I don't think you are the one to make them for the members here, no offense, as you are not experienced enough as a home chemist. There are members here who do this hobby for decades, so it would indeed be nice if they would make a safety guidelines thread.

What I have in my lab as safety and environmental features (I do this almost 5 years now):
-a home made fumehood wich works fine
-fire extinguisher + fire blanket
-lab coat, goggles + vinyl gloves
-a fireproof storage cabinet
-Proper waste bottles: organic waste, metals (inorganic waste) and solid waste

You will also need running water to wash stuff of your hands if it gets on you.
I want to buy a small eye wash bottle. Once I was surprised by a reaction a few years ago, wich was very stupid. When you add dop by drop IPA to a 1:1 mix of HNO3 and H2SO4, you get a very vigorous reaction, but no incontrollable. After that (inexperience

) I premixed the EtOH and HNO3, and added H2SO4 drop by drop. At once the reaction was so violent that a spray of acid was ejected from the test tube and a got a few very small drops on my face(and one on my goggle), it really hurt, but nothing serious as I put my face under running water. I was happy to always wear goggles, whatever I do.

I don't have MSDS sheets of my chemicals. I know the hazards before I buy them, and most vigorous reactions between chemicals I can predict by experience or knowledge.

[Edited on 25-5-2011 by Jor]

The WiZard is In - 25-5-2011 at 05:18

Quote: Originally posted by Jor

And gloves are not essential! I rather don't have them on with acids like HCl or other mild corrosives. If you have a drop on you can reacts immediately as you feel it.

I only wear gloves when handling conc. H2SO4 in larger than mL amounts, strongly poisonous substances (cyanide), chronic poisons (lead, mercury), bromine and sensitizers (like Pt and Cr compounds).

I use thin vinyl gloves. They are resistant to most acids, mine even keep bromine outside for long enough so I can take of my glove.

I would add strong hydroxides, e.g., sodium. They cause
painless burns... until your skin dissolves ... half way the bone.

I would mention in passing. Chosen only because I shelve them.

Lunn & Sansone
Destruction of Hazardous Chemicals in the Laboratory

Manufacturing Chemists Association
Guide for Safety in the Chemical Laboratory

CRC Handbook of Laboratory Safety
2nd edition

mewrox99 - 26-5-2011 at 00:55

Indeed NaOH is nasty to get on the skin. At least you can quickly notice the soapy feel

[Edited on 26-5-2011 by mewrox99]

woelen - 26-5-2011 at 01:20

It indeed is very personal how you perceive risks. One person may find something very dagerous, while another feels comfortable with the same thing.

I also never use gloves, they irritate me and give me less dexterity. I do have eye protection though. Even conc. H2SO4 I handle without gloves. Because I do not use gloves, I use pipettes for some of the most corrosive chemicals (liquid Br2, fuming HNO3, oleum, but not conc. H2SO4, normal HNO3, conc. HCl). I have tens of pasteur pipettes and I always clean them with distilled water and always have at least 20 of these in a perfect clean state, such that I can pipette chemicals from their bottles without contaminating chemicals.
In this way, I do not have to pour the chemicals and I do not have to lift the bottles (I keep them in a heavy glass basin, when I take something from them with a pipette).

I also have working bottles of most chemicals. E.g. I have a few liters of H2SO4, but I have a small 100 ml from which I work and the main stock is at another place. This assures that the main stock remains good and cannot be contaminated and in case of severe mishap, the main stock is safely put away. The smaller bottles also are easier to handle. Pouring some conc. H2SO4 from a 100 ml bottle is a lot easier and safer than doing this from a large and heavy 1 liter bottle or even 2.5 liter bottle.

I do not have a proper fume hood, although I have a kitchen exhaust under which I can do experiments with moderately toxic vapors or gases. The really toxic ones I do outside, when weather conditions are suitable.

I do not agree that a full risk assessment needs to be made for each experiment. Usually, when I synthesize chemicals in somewhat larger amounts, then I think over what risks there are and if necessary I take counter measures, but for small test tube scale experiments I just try things and from experience I know which ones may be very violent and which ones will be tame. If combinations containing solid strong oxidizers are involved, concentrated strong acids or very strong reductors, then you can expect a violent reaction.

I my lab I have a fire blanket, a big bottle filled with fine sand, and a CO2 fire extinguisher. Besides that I have running water in my lab. All of these can be grasped directly and are near the entrance of the lab.

Magpie - 26-5-2011 at 08:45

I, too, agree that perceived risk is personal and varies with each experiment.

I don't do a formal, written risk assesment, but risks always are a part of planning my experiments. I'm not saying that they would be a bad idea, but if you invoke too much rigidity the experiment may never get done due to the effort involved.

I have latex gloves which I wear if working with toxic material. I'm always amazed at how visibly contaminated these gloves are when I finish some experiments.

I have some thicker nitrile gloves that I use when working with con sulfuric acid, nitric acid, and oleum. I know this is not the best material but it is thick enough to give initial protection yet still allow reasonably good dexterity.

I have a good fume hood which covers a multitude of sins. I even turn the fan on when pouring powders (esp NaOH) as it is amazing how much gets dispersed into the air you would ordinarlily be breathing.

be careful out of da lab toooo

The WiZard is In - 26-5-2011 at 11:14

[CaO and moisture forms calcium hydroxide.]

This Week
Pitch battle
Lime has no place on sports fields

BURNS experts are this month calling for a ban on lime based markings on sports pitches. The move follows an incident during a soccer game in Wales in which a goalkeeper was seriously burnt by the cor¬rosive alkali as he made a goal line save¬ and fell directly onto fresh lime markings.

Although hydrated lime calcium hydroxide is only used rarely, owing to its known dangers, it is still used on some pitches, says Derek Walder, a consultant to Britain's Institute of Groundsmanship. "There are probably a lot of amateur clubs that still do it," he says.

A team led by Viswanathan Narayanan at the Welsh Centre for Bums and Plastic Surgery at the Morriston Hospital in Swansea report in this month's edition of the journal Burns that the goalkeeper's lime burns covered 5 per cent of his body. He needed surgery to excise dead skin and to apply skin grafts. "We'd never seen this in a footballer before," says Ian Josty, a burns specialist and colleague of Narayanan. "It's more common to see it as a result of working with cement powder. People get that in their wellies and the addition of a bit of moisture gives a chemical burn."

In their paper, the burns experts blame "ignorance or inertia to change" among football clubs for the continued use of lime markings. There are perfectly safe pitch paints based on vegetable dyes and these are in wide use among professional clubs.

"There's nothing in the rules of the game to say what the pitch markings should be made of," says Joe Guest of the Football Association. "It just says the pitch should be marked with lines." However, the use of hazardous substances is barred under

the Control of Substances Hazardous to Health (COSSH) Regulations. But Walder believes a number of clubs particularly those at grassroots level may be unaware of the regulations.

Narayanan and his colleagues want sports authorities to heighten awareness of the harmful effects of lime and the existence of safe alternatives. In addition to reducing preventable injury, they say, safe markings could prevent costly litigation.

Paul Marks
New Scientist 2 December 2000

More at: Burns (vol 26, p 754)

Arthur Dent - 26-5-2011 at 11:24

When I experiment with potentially flammable chemicals, I always have 2 large plastic pails, one filled with sand and another filled with cat litter. I have no extinguisher, but I intend to buy one eventually.

Also I have wide glass petri dish/covers on hand to put on any beaker that gets filled with a potentially flammable chemical in case it ignites without exploding, this applies to beakers 400 ml or less.

My acid bottles are in a large plastic dish (acid resistant of course) in case of spillage or breakage. The HCl bottle is in a pail outdoors.

I have no hood, but I devised a quick and safe way to direct noxious gases (in small quantities) outside using glassware with ground glass joints, fitted with a taper glass vent connected to a vinyl tube bubbling through 2 gas washers (600ml erlenmeyers with sidearms) before being directed outside through another long lenght of vinyl tubing.

I limit my vacuum experiments to the vacuum attained with a little plastic water aspirator, anything that requires deeper vacuum, I won't do, period.

I use gloves with HNO3 and H2SO4 but I don't with hydrochloric and NaOH... maybe i'l start doing so after seeing the picture above.

This is an interesting thread. I'll contribute other ideas as they come to my forgetful mind...

Robert

entropy51 - 26-5-2011 at 13:13

Quote: Originally posted by Arthur Dent

I limit my vacuum experiments to the vacuum attained with a little plastic water aspirator, anything that requires deeper vacuum, I won't do, period.

The force on the glassware is the surface area times (atmospheric pressure - pressure in the glassware).

If you do the math you will find that the force is essentially the same whether the pressure in the glassware is 20 torr from a water aspirator, or 0.001 torr from a good vacuum pump, since atmospheric pressure is about 760 torr.

There is no less danger of implosion when using "just" an aspirator vacuum.

DJF90 - 27-5-2011 at 04:20

Face shield should be worn when working with reduced pressures. Whether you wear one or not depends on how willing you are to take a faceful of broken glass. My top tip for n00bs/k3wls is to find a different hobby, or fix up and be serious about chemistry.

Hexavalent - 1-1-2013 at 14:00

When working with glassware under pressure or vacuum, I always have an acrylic blast shield in front of the apparatus and I usually also wear a face shield.

For me, safety goggles and a lab coat are the bare minimum, for more serious work I'll wear nitrile gloves (thicker ones for highly toxic/corrosive materials, and insulated ones for hot/cold work) and for experiments that need it, I'll wear a respirator, use a fume cupboard or work outside.

I've a tip for handling large bottles of corrosives: when pipetting from them, I clamp them securely to a lab stand to help prevent them from falling or tipping. The same is used in professional laboratories, actually, for pyrophoric liquid transfers.

Pyro - 2-1-2013 at 14:55

Quote:

I have latex gloves which I wear if working with toxic material. I'm always amazed at how visibly contaminated these gloves are when I finish some experiments.

I concur to that Magpie! latex is actually the only glove I wear. I find Nitrile horrible, it's sort of ''sticky'' if you know what i mean. and if I see anything on them that looks like it will eat through I just change it/them.

for fire i have: completely brick fire-proof lab and a CO2 fire extinguisher, I also keep stuff like coats far away

personal safety stuff: safety glasses, gloves and lab coats

chemical storage: terrible I know. All my solid chemicals are on one table (they also collect dust)
and my liquids are arranged by type on those ledges. acids, alcohols and others. and they will stay that way until I find some cupboards.

as for precautions:to get to running water (or out of my lab) I need to climb up about 40 steps from subterranean level to the first floor, but once I'm there I have sinks and toilets, so all i have to do is ''insert head and flush''

but eventually i'll get an eyewash station.

All I got for bottles are 1l and 2,5l bottles. they are great being brown glass and such, but heavy (especially filled with conc. H2SO4 or HNO3!) and hard to pour without spilling.

Woelen: how do you wash those pipettes? I have always had problems with washing them. I just use them as disposable pipettes. at 0,07 eur/piece, they dont seem worth washing

[Edited on 2-1-2013 by Pyro]