Question:  How are detector loops installed?
Answer:  There is a variety of equipment.  The photo below shows a round loop saw (Caltrans Type E).  The second photo shows a saw that cuts straight lines.  This saw can be used in combination with the previous to cut the lead in slots or can be used by itself to make a square loop (Caltrans Type A or D).  It takes about 5 minutes to cut a Type E loop, 10 minutes to cut a Type A loop, and 15 minutes to cut a Type E loop.  The cutters have a jet of water on the blade to keep the blade cool.  Cleaning up the water takes longer than the loop cutting, and must be done before wires can be installed in the sawed slots and then bound in place with loop sealant.  All combined, the work takes between 30 and 60 minutes per 6' x 6' loop.