maybe this is a stupid question, but in light of this article, why is it that in meter socket enclosures they send cardboard to cover the live parts after installation instead of the plastic cover?

Now if we can just get the supply houses to keep the things in stock. I used them for years. Always thought they were required but never looked for the relevent code section. Just made plain good sence!

The whole point here is safety. It is not to keep the Qualified Electrician from sticking objects into the openings but, the unqualified, children that can reach the panel cover, and homeowners. It is also a preventative measure to keep objects from accidentailly going through openings and causing shorts, etc. It also contains sparks that may or may not fly out of the panel in a short or fire condition spreading the situation further. It also lessens access to larger size bugs and rodens, which in the attempt can climb through the opening and be electricuted and cause damage and possible fire.

At times in an old panel, perhaps the KO's were removed by some handyman or other change, We have used a 4" Square blank cover secured with screws and nuts to return the deadfront to a solid face.

tape won't do the job!!!!!

Hmm, I thought this was generally already required. But in the light of Ms Mann's concerns regarding sticking objects into live equipment, wouldn't a more practical safety item be one where these circuit breaker blanks be mechanically held, instead of the pop and pull plastic tab sort; much like how large knock out seals are held with a bolt and flange thus necessitating a minimum of tools to remove it?

This has been required for years in Washington State.