I too am VERY cautious when working with tubes w/o integral implosion protection. Think about it...even in the 1940's, well before the heyday of injury lawyers, manufacturer's were plastering "caution" notices on both the tubes themselves and on the insides of TV cabinets, warning about the possibility of serious injury when removing or replacing even a small 10 or 12 inch CRT, let along a 21 inch or larger. The service manuals of these sets even went so far as to highly recommend eye protection and arm protection.

When you consider how many things of that era were also truly "dangerous", yet carried no warnings (ie big ole' GE fans with brass blades and little to no guarding), there was obviously some well-founded basis for the concerns, even outboard of strict legal liability.