Which equipment is essential for checking the alignment of structural components during erection?

The laser level is essential for checking the alignment of structural components during erection because it provides a precise and easy-to-read reference point for horizontal and vertical alignment. This tool projects a consistent beam of laser light that can be used to gauge whether structural elements, such as beams, columns, and other components, are installed at the correct angles and heights. Accurate alignment is critical in ensuring structural integrity and safety, and the laser level allows ironworkers to make real-time adjustments as needed for proper placement.

In contrast, the other equipment options serve different purposes. A sling is used primarily for lifting and securing loads, not for measuring alignment. A forklift is essential for moving heavy materials on site but does not provide a means to check alignment. A jackhammer is typically used for breaking up concrete or other hard surfaces and is not related to checking the alignment of structural parts.