Containment Levels -Question

[Ken Navarre]

This from a previous post:

"I think that Ebola could be safely handled with P3 containment or even 
carefully followed P2 conditions. BL4 isn't perfect, just read about hole 
in glove incidents."

For those laypersons out here, could someone post a brief description of 
the different containment levels that are used in labs/research facilities?
Or, a place to find the information.

Thanks for the time and info.

Ken Navarre

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