@tsarstepan,
Tsarsterpan just closing the browser is a very very very odd way for a business to filter the internet and I question that in a large business setting that his privilege level would allow him to install other browsers as you had suggested.
If I was the IT department I would had the machines locked down as a matter of course to prevent someone from running foreign software that might contain malware of one kind or another.
Also he seems from the lack of information and the tone of the question not to be up to the task of installing other browsers even if he did have the system rights to do so.
If I was him I would had just picked up the phone and dial the IT department to solve the problem of the browser closing on me as I do not think it had a thing to do with filtering the net.