Does the excavation competent person have to be on site at all times?

Not necessarily. The competent person must be present to identify situations that could result in hazardous conditions and to ensure that corrective measures are taken. Daily inspections prior to start of work in the excavation are required, as well as throughout the shift as needed. It is therefore subject to the conditions present at each individual site whether or not a competent person is required to be present on site at all times.