Strangely, GT6 has many kinds of gas lasers, but only three kinds - helium, helium-neon, carbon dioxide - are useful, and the rest are actually useless, although they are illustrated in tooltip. Maybe they can be added useful in the future…
In addition, I am looking forward to LU transmission in the air, LU transmission in the air will be lossy, and will cause damage to touched entities (which may make laser hazard sign useful… )