Visible LASERs

Generally speaking LASERs do NOT produce visible beams of light, regardless of application. Most you should see is the dot marking where the laser hits. This tag is limited to non-weapon lasers due to prevalence of visible weaponized lasers.

This also includes lasers in weapons when the laser is only used for pinpointing or otherwise detecting the target.

However, it should be noted that if the laser produces a visible dot, then it is entirely realistic that the beam should be visible wherever it collides with smoke or fog and/or many other translucent materials.

Example from Fade to Black: