Which gas is commonly used in construction lasers for line and grade control?

• A. Helium
• B. Nitrogen
• C. Hydrogen
• D. Oxygen

Answer: (A)

In construction lasers, helium is commonly used because it is an efficient and effective medium for laser operation. Helium lasers can produce a highly focused and visible beam, which is useful for precise line and grade control in various construction applications. The properties of helium allow for the safe and reliable emission of laser light, making it suitable for outdoor and indoor use where accuracy is critical.

While other gases like nitrogen, hydrogen, and oxygen may have their uses in different contexts throughout industry and science, they do not provide the same combination of visibility and operational efficiency for laser devices as helium does. This distinction highlights why helium is the preferred choice in the specific application of construction lasers.