RPG mechanics exist to give structure and consistency to the game world, true, but at the end of the day, you’re fighting dragons with algebra and random number generators.
Unofficially, I like to adapt modifiers from the weapon range table on p.185 ... Short (-0), Medium (-1), Long (-3), Extreme (-6). I use sniper rifle ranges for vision, assault rifle ranges for hearing, holdout pistol ranges for odors.