Laser levels are replacing water levels and transit compasses on modern construction sites. Laser levelling finds the straight line for sloped or true horizontal and vertical measurements, and retains a nonstaining laser-generated chalk line. A rotary laser level shows a horizontal measurement on every wall in a room. Contractor and residential work is aided by laser illuminated plumb and level lines.
Install batteries or a rechargable battery pack depending on the particular laser level. Set the instrument on a fairly level surface. Adjust the level with the water bubble on top if necessary. If the instrument has a self-levelling feature, it will only work on a surface that's within five degrees of being level. A tripod provides adjustable support for uneven surfaces. Wall mounts are used to position the laser for ceiling work.
Check the accuracy of calibration for a laser level. Check a horizontal straight line by placing the unit on the floor near one end of a long wall. Turn on the laser and mark the line with a dot at either end of the wall. Move the unit to the other side of the wall. The level is properly calibrated if the line intersects with the dot on the far side of the wall. Use a plumb line to test the vertical projection. Calibration is proper if the beam lines up with the top and bottom of the plumb line. Check a rotary laser by positioning it between two walls that are 50 feet apart. Set the unit with the point directly on one wall. Turn on the rotating beam and measure the line height on both walls. Turn the unit to face the other wall. Measure the line height on both walls. A variation of 1/8 inch is tolerable. Bring the instrument to an authorised service dealer when it's in need of calibration.
Turn on the laser level to project a mark that's horizontal and level, sloped, vertical, crossing or horizontal at 360 degrees. A rotary laser level can be set to show a horizontal or sloped line of limited length, a plumb line or a horizontal line at equal height on every wall of a room. An electrician may use a rotating laser level to install light switches and receptacles at even heights around a room. Other models can project straight lines vertically, horizontally or both. Use the appropriate buttons for marking selected measurements. Many laser devices come with remote controls to make adjustments from a distance.
Care and Safety
Turn off a laser level and return it to the carrying case with the lock set when not in use. Remove the batteries or battery pack for long periods between uses. Wear reflective eye protection and never look directly at the beam source, or point it at anyone. Position the instrument so workers aren't facing it. Avoid dropping or jostling the unit. Check the calibration often and clean the lens with a soft cloth or moist cotton swab. Do not use solvents for cleaning.