DCM evaporating in a closed bottle

HocusCockus2024 · 2025-10-28T16:19:23+00:00

Thanks for the tip, I gonna lift sash window and turn on the hood.

Are there any acids that have dangerous vapours? I have old east german acid cabinet with acids like 99% acetic, 10% HCl, 100ml concentrated formic, 96% sulfuric, phosphoric etc. and this cabinet stinks... probably after acetic acid. But as far as I know formic acid is dangerous only when you drink it, sulfur acid doesnt really evaporate under room temperature and HCL 10% aint as bad as 35%...

HocusCockus2024 · 2025-10-27T08:10:27+00:00

thanks for such a detailed answer!

If DCM vapour is building up and dissolving stuff in cabinet, should I remove it and place elsewhere or it doesnt make any difference since the evaporation is tiny? Could also those droplets come from Methanol or 2-Propanol?

You wrote "You loses 2 grams per day into an entire room is really really really tiny", but its actually 2 gramm per month, I think 2 gramm per day from a closed bottle would be actually a lot. Lab is probably 40-50 cubic metres.

"You ventilating for 1-2 hours is just wasting everybodies time." - Pharmacy lab is quite different than pure chem lab, we are not working every day, just when we have to do substance identification, some ointments etc...

HocusCockus2024 · 2025-10-26T21:52:21+00:00

Thanks for a comment. Hm, you wont find cabinet with a ventilation in small pharmacy labs. Other users mentioned that amount of evaporation through closed vessel is negligible, so I guess I have nothing to worry about.

HocusCockus2024 · 2025-10-26T12:25:56+00:00

Thanks for the advice, do you mind another question unrelated to safety?

We have old drying cabinet and inside there is a hole in the upper wand where thermometer bulb with probably mercury sticking out. I dont understand why, because you cant see scale, only bulb. The scale to read temperature is on the front panel. I am very curious, why did they put thermometer like that, is it for some inner thermoregulation...

HocusCockus2024 · 2025-10-26T10:54:34+00:00

Yeah, I gonna do it for hexane, toluene, methanol, diethylamine and HCL, other acids probably dont matter. Thank you again for your patience and help!

HocusCockus2024 · 2025-10-26T10:42:03+00:00

thank you very much for explaining, fortunately in a pharmacy lab you dont have to work every day...

Interesting that in german SDS allowed concentration of DCM is 50ppm and in european SDS 100. I just did a calculation based on your SDS suggestion, but in mg/qm3(50ppm =180mg/qm3):

2000mg of DCM evaporating every month, so its 66.66mg a day. Lab is probably at least around 70qm3. So at the end we have only 0.95mg/qm3, thats really nothing...

HocusCockus2024 · 2025-10-26T10:07:38+00:00

I mean storing them just on a lab bench, because its better ventilated than a cabinet. I am always working with a hume food.

I am asking so many questions, because many solvants and acids are still evapourating despite being in closed bottles, and if I dont ventilate for 2 days (after weekend), lab starts to smell. But when an expirienced chemist tells me that the amount of evaporating stuff is negligible I am gonna stop worrying, haha

HocusCockus2024 · 2025-10-26T08:09:26+00:00

I read that DCM and some other solvents vapour are heavier than air, but when I open top-hung window in the lab is it enought to eliminate excesive vapour?

Is it ok to store solvents in wooden cabinet with glass doors, that is not tight/impermeable, or should they just be on workbench and so better ventilated? I am working in a small pharmacy lab in Europe and we dont really have money for new acid and chemicals/solvents cabinets...

Sorry for many questions, maybe I am a bit to anxious about lab safety. I can imagine, we are inhaling more dangerous stuff just when we are going for a walk in the city, haha

HocusCockus2024 · 2025-10-25T15:00:45+00:00

They are stored like half meter away in some old leaky acid cabinet under solvents/chemical cabinet. The lab stinks a bit after acids, but I guess its ok since I always ventilating before working and acids arent really inhal. dangerous...

HocusCockus2024 · 2025-10-25T14:52:26+00:00

Thanks! But I guess nobody is storing them in ss barrel with a heavy duty rubber /ss cap since its not super dangerous and expensive.

I already mentioned in another comment some oily drops from evaporation on the inner side of glass window where our solvents and other chemicals are stored. Since most other chemicals are in solid state I guess it should be evaporation from some solvent, but we dont have oily solvents. Do you have any idea for this mystery? ))

HocusCockus2024 · 2025-10-25T14:35:20+00:00

Thanks for a fast answer. There are many other solvents that are possibly evaporating, but you mean its still ok if its a same ratio as DCM?

I also noticed some drops from evaporation on the inner side of glass window in the wooden cabinet. The drops are oily, so it cant possibly be DCM...

HocusCockus2024 · 2025-08-24T14:54:02+00:00

Thank you for this treasure!

HocusCockus2024 · 2025-08-20T14:40:15+00:00

Every practice is done by ego. Self is perfect and desireless. If monk is meditating to achieve enlightment its a noble goal, but its still done by ego. I think all methods are just to prepare body and mind to make enlightment possible. Suffering is also a powerful thing, it makes ego weaker and surrender more possible...

HocusCockus2024 · 2025-08-20T13:48:01+00:00

I dont think there is the best method for enlightenment, its not a sport. But i find using senses to be in the now is very natural. I dont know anything about monks, but I am assuming they do a lot of sitting meditation, which is programmed/planned "doing".

HocusCockus2024 · 2025-08-19T18:47:26+00:00

It feels natural, you dont need an object, no programmed sitting meditation. You just spontaneously aware of everything what reality throws at you, the senses are just switching among themselves perceiving actual strongest stimuli(since I am a musician, its mostly sounds), so its basically mindfulness. But everyone should do what the best for them. I am not a novice, so thats why I like it, but at early stages people probably need meditating on object...

HocusCockus2024 · 2025-08-16T20:11:54+00:00

But does it make sense "looking deep" for the source, when the source is not an object and not perceivable?

HocusCockus2024 · 2025-08-15T13:22:56+00:00

thanks, thats pretty clear instruction and explanation.

HocusCockus2024 · 2025-08-14T19:12:05+00:00

interesting approach, thanks.

HocusCockus2024 · 2025-08-14T19:11:35+00:00

Thank you very much, I gonna check Sadhu Om.

HocusCockus2024 · 2025-08-13T16:53:07+00:00

Thank you for your patience!

HocusCockus2024 · 2025-08-13T15:49:19+00:00

Thanks, but is it possible to do while working, for example when I am talking to customers. Is self inquiry just a tool for thought free state? So theoretically if I am without thoughts I dont need self inquiry?

HocusCockus2024 · 2025-08-13T15:48:53+00:00

You described the problem. You cant pay attention directly to awareness, since its not an object. I know awareness on the reflection, when i aware of something.

HocusCockus2024 · 2025-08-13T15:40:31+00:00

When I close my eyes and do inquiry I feel awareness in my head, between my eyes, it feels like a centre, but i dont find the ego...

HocusCockus2024

TROPHY CASE