Please note that you should only use point spacing for LiDAR data.
In a LiDAR point cloud dataset, points are located throughout the site with a fixed distance between them as they repeat in a grid-like pattern throughout the site. This point spread metric measures the largest distance between either the rows or columns of points, which ensures full coverage of the site and guarantees accuracy.
This image shows a LiDAR point cloud file with good point spacing.:
This image shows a LiDAR point cloud with bad point spacing:
Noise & Ground Thickness
Every point cloud file will have a thickness that determines its accuracy. This thickness should be measured on a hard surface like a paved road and should be less than 1/5 of the desired contour interval. So, if 1-foot contours are requested, the thickness should be under 0.2 feet.
Currently, there is no simpler metric to follow in terms of thickness, so the 1/5 rule should be maintained to ensure that the data is accurate.