Hello
I work for a company that performs building condition assessments for commercial buildings. These assessments
are visual only so no testing of any sort is involved. Essentially the older a system is in the building, the
sooner a lifecycle replacement should be recommended.
The assessments include electrical distribution systems. Oftentimes we are in older buildings from the 1950s
to 1970s and even earlier and most will have the original distribution present. Sometimes we want to open
the panel doors to see the breakers inside etc to help determine if the panel is original or if it is newer. It is
often difficult to determine an age for panels this way, this we know. But we not electricians and that is
all we are permitted (and want) to do.
In many cases, panels are not maintained per NETA MTS best practices, owners just do not bother. To me
this means some of these panels probably haven't been touched for years. My understanding is that the
requirement for EGC/EBC in electrical distribution systems did not come into play in the NEC until around
the mid 1970s.
My concern is this - when we open panel doors to look inside for distribution systems from the 1970s and
earlier, we are putting ourselves at greater risk for potential shock from touching the doors should a ground
fault be active anywhere in the distribution because of the absence EGC/EBC. And there may be a host of
other reasons why the risk would be greater that we are unaware of.
What is your opinion ? Are we at greater risk for electrical shock ?
Thank you
I work for a company that performs building condition assessments for commercial buildings. These assessments
are visual only so no testing of any sort is involved. Essentially the older a system is in the building, the
sooner a lifecycle replacement should be recommended.
The assessments include electrical distribution systems. Oftentimes we are in older buildings from the 1950s
to 1970s and even earlier and most will have the original distribution present. Sometimes we want to open
the panel doors to see the breakers inside etc to help determine if the panel is original or if it is newer. It is
often difficult to determine an age for panels this way, this we know. But we not electricians and that is
all we are permitted (and want) to do.
In many cases, panels are not maintained per NETA MTS best practices, owners just do not bother. To me
this means some of these panels probably haven't been touched for years. My understanding is that the
requirement for EGC/EBC in electrical distribution systems did not come into play in the NEC until around
the mid 1970s.
My concern is this - when we open panel doors to look inside for distribution systems from the 1970s and
earlier, we are putting ourselves at greater risk for potential shock from touching the doors should a ground
fault be active anywhere in the distribution because of the absence EGC/EBC. And there may be a host of
other reasons why the risk would be greater that we are unaware of.
What is your opinion ? Are we at greater risk for electrical shock ?
Thank you