[kriggy]

Hey guys, I realy screwed up today (literaly) so I decided to make this post about my accident so others will learn from my mistake.

Anyway, I had a full waste bottle (2,5 l of non halogenated solvents) and I wanted to put it to waste cabinet but I couldnt find keys so I decided to leave it for later. I closed the bottle and screwed the top too much. In about 30 mins, I hear a loud "pop" and yellow waste started to spill into my hood. I tell you its not pretty to see. In about 30 seconds my hood is  totaly covered with yellow solvent waste in with depth of maybe 3mm (sadly I was not able to take a photo for obvious reasons). What to do next?

1) don´t panic
2) turn the air conditioning in your hood (or whatever its called) at max
2a) if the bottle is broken at top, get a jar and put the bottle into it to avoid any leaks and clean
2b) if the bottle is broken at bottom (like mine) well, remove any sensitive stuff (TLC´s for example) from hood asap to avoid damage. Chemicals in glass/plastic bottles can survive for while but get them out as soon as you can. Remove everything you can from the hood
3) take tons of paper towels and soak the waste into them. Wear double gloves at least, double gloves + rubber gloves are recomended
4) take a jar or pail to put the soaked towels into (and squeeze the soaked solvent out of the paper towels so you can pour the solvent waste into another waste bottle and get rid of it), keep it in hood!
5) repeat 4
6) repeat 5
7) because you had the hood turned on max, most of the waste solvent is either soaked in towels and now there is only non-volatile stuff in the hood
clean your hood with suitable solvent (acetone, methanol whatever you use for cleaning)
9) enjoy the cleanest hood in your lab

TLDR: dont screw the bottle too much

Two pictures as attachment:
a) cracked  bottle
b) my hood before step 8

[mjc123]

Thanks for the advice (and for being willing to admit your own mistake). There are a couple of additional points I would make; they may or may not be relevant to your incident.

1. How full was the waste bottle? People often fill them up to very near the top, but this can be dangerous. To illustrate: a quick google suggests a typical value for the volumetric thermal expansion coefficient of an organic liquid is ca. 1.2 x 10^-3 K^-1. So if T rises by 10K, the increase in volume of ca. 2.5 L liquid is ca. 30 mL. If you leave very little volume above the liquid, and tighten the cap, you can generate high pressures if the temperature rises. If the cap is left loose pressure can be released, but that may mean unpleasant vapours escaping, or even liquid overflowing if it expands too much. The better procedure is not to overfill the bottle in the first place. When the liquid gets up to the shoulder, it should be considered full and disposed of. Don't fill it up to the neck. (Mutatis mutandis for differently shaped containers.) I doubt if "screwing the top too much" was really your problem; I suspect overfilling.

2. Was it near any sources of heat? It looks as if you had some heating plates in the fume hood - were they on? Is the lab air conitioned - how much does the temperature vary? Was the bottle in direct sunlight? etc. etc.

3. Were there any incompatibles? Clearly you separate halogenated and non-halogenated waste, but don't assume that as long as you do that it's automatically safe. Were there any substances in the non-halogenated waste that might have reacted with each other?

4. Having procedures that encourage and facilitate timely disposal of wastes (like being able to find the key!) is important. People rightly pay a lot of attention to safe lab practices, but these administrative considerations matter too!

Congratulations on surviving this incident and dealing with it safely, and Happy (and safe) Reacting in the future!

[Borek]

Glad to hear it ended up well. s#*$ happens. IMHO the first point - don't panic - is the most important one. Not always easy though, I know.

[kriggy]

mcj123:
1) It was like super full. Basicaly I poured some stuff in and it overflown (overflew?). I didnt realy see inside because its dark glass and none was in my hood for month give or take. Our disposal cabinet is in a basement so I closed it and went searching for keys and then forget that I closed to too tight. Its still better that it got off in hood instead of elevator

2) yes but the plate that was on overnight was turned off about hour or two before it happened. I have no idea about the temperature, we have some 23°C aprox. But the air conditioning is not great

3) not sure, since I was not in a lab for over a month.

4) yeah its good idea to take care about it. the problem with keys was probably that someone was in the basement at the moment but I didnt want to go there without keys in case that just someone didnt return them at their common spot

[Corribus]

We have a policy to limit the volume in waste container to 80% of whatever the max volume is. This also makes the big carboys easier to carry.

Also, you may want to have your lab invest in a proper chemical spill kit. Paper towels are not really a great way to clean up a solvent spill, especially if you're just throwing them in the garbage can.

[kriggy]

Thanks for suggestions, Ill talk to my boss about it (he was not there yesterday).
btw we have special thrash can for chemical waste, maybe not perfect but better than ordinary trash can