Soldering does not generate metal vapor. Soldering fumes are burnt flux residues, which are often acidic and quite nasty.
Laser cutting or engraving makes even worse fumes and requires seriously good filtering. I personally think they're nasty enough that it is irresponsible to just dump this stuff outside into the environment without cleanup but it's certainly better than breathing it.
liquid lead has a vapor pressure (it was easy to google) but at what temperature or sustained duration it would be dangerous I don't have the background to assess. in terms of duration, heavy metal poisonings are cumulative over time.
back when I was a young electronics hobbyist, back in the days when there was still lead in solder, man I loved the smell of flux burning off! I've never noticed any ill effects, but there is still time for me to get emphysema or lung cancer.
if you do use a filter make sure it captures metal vapor, which is unlikely with a regular hepa filter.