[Plontaj]

I know that often big companies are embarrassed for admitting that their working place is not safe, so I'm asking you anonymously (if you work at that place... but if not, I'm only asking you for a little imagination .).

Into things:
I'm looking for substances that could be dangerous at your place of work like: nitro-compounds, nitroso-compounds, also peroxides, ethers, and similar compounds, pharmaceuticals and so on. Generally hazardous compounds, which have self-oxidising properties.

Thanks in advance, because It could be useful to my thesis.

[Corribus]

Well, different people have different barometers for safety. In graduate school we practically bathed in THF. Where I work now, the safety people treat it like it'll explode if you look at it wrong. ("BUT... PEROXIDES!!" he screams, running for the blast shield adorned with a crucifix).

More to the point, any chemical can be dangerous if you don't respect it. Categorically labeling things in a laboratory as safe or hazardous is a fallacy of false dilemma. In my opinion, safety personnel who institute policies based on the presumption of treating everything like polonium do employees (and particularly students) a disservice by discouraging them from actually thinking about the authentic hazards of laboratory work and acting according to a real risk assessment. Of course, I understand the liability makes this a necessity but....

Oh man I gotta get off that soap box before I get going. Question is very vague. It's not really clear what you are after. Look in any lab and you'll find hundreds of "dangerous" chemicals, many of them oxidizers.

[curiouscat]

Other factors that matter is scale. Some chemicals are pretty innocuous in lab scale trials with mg or gm yields but when you start thinking of hundreds of kilos one becomes more wary and careful.

Another factor is who is handling them. A PhD or Post doc gets a lot of leeway (perhaps undeservedly so?) and he's supposed to be able to think the hazard through and plan accordingly but when you think of under-grad labs or even industrial R&D where you might be delegating the runs to a number of technicians, outsourced to a contractor  etc. one tends to be more careful. (there are exceptions; some techs are super experienced in hazardous stuff)

Another subtle point (perhaps subjective) is the subject-degree of the person handling the substances. I'm a Chem Engineer myself but I'd tend to intuitively trust a chemist with some stuff that I'd cringe to let a Chemical Engineer handle.

Finally, goodwill perceptions factors a lot in these descisions. An industrial R&D Lab situated in populous NJ is very wary of making it to the evening news, even  for a somewhat not-so-dangerous incident.

[Enthalpy]

You could have a look at the semiconductor industry. The compounds used there are sometimes explosive (silanes), often toxic (hydrazine, varied organo-something, phosphine and many more), corrosive (fluoro-anything). People who use them are not always chemists as they need more skills. In production plants things go more routinely, in development people have to use more varied compounds in diverse environments.

What about launcher rockets? Spark- and friction- sensitive solid propellants. Hydrazine, Mmh, Udmh, nitrogen tetroxide in hundreds of tons. What limits the accidents is that people are very wary of the risks and safety measures are followed there. Makes for impressive videos on youtube.