Screwdrivers

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DBoone

DBoone

Senior Member
Location
Mississippi
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General Contractor
Every screwdriver I have seen with a rubber type handle has "warning not insulated" inscribed on the handle.

:blink:

Whats up with that?

What am I missing?
 
DBoone said:
Every screwdriver I have seen with a rubber type handle has "warning not insulated" inscribed on the handle.

:blink:

Whats up with that?

What am I missing?
Click to expand...

The fact that they are not tested and listed for live voltage contact. Such as the ones that have the shank and handle covered and listed for xxx# of volts
 
DBoone said:
Every screwdriver I have seen with a rubber type handle has "warning not insulated" inscribed on the handle.

:blink:

Whats up with that?

What am I missing?
Click to expand...

Just an instruction from the manufacturer to help defend in a lawsuit if the person used the screwdriver on a live circuit and go shocked.
 
DBoone said:
Every screwdriver I have seen with a rubber type handle has "warning not insulated" inscribed on the handle.

:blink:

Whats up with that?

What am I missing?
Click to expand...

Look at the ones that say they are insulated and compare differences, same with pliers, cutters, and other hand tools. Also pay attention to what voltage they are insulated for.

Reality is the screwdriver you first mention is insulated, but not listed, tested approved and the manufacturer does not claim you are safe to use it for live work, this is their disclaimer so you can't sue them if you do get hit while using it in a way it wasn't necessarily intended for.

According to the instructions on most, you are also not supposed to use screwdrivers as chisels, punches pry bars, and many other things that people often do use them for.
 
kwired said:
... Reality is the screwdriver you first mention is insulated, but not listed, tested approved and the manufacturer does not claim you are safe to use it for live work, this is their disclaimer so you can't sue them if you do get hit while using it in a way it wasn't necessarily intended for...
Click to expand...

To this point, people often ASSume that just because something is plastic, it is insulating. ALL things that we call "insulators" are actually conductors, some are just better conductors than others, so the difference is in the degree of conductivity. Most resin based plastics have a resistance of over 1012 ohm/sq. in., but some could technically be as low as just 10 ohms/sq. in.! For example, some screwdriver handles are SPECIFICALLY designed to be conductive, in order to prevent ESD for working on sensitive equipment.

The plastic that is used on an "insulated" screwdrivers, in conjunction with the rubber grip added to it, provides that very high resistivity, thus protection against a certain DEGREE of conduction of significant voltages, up to the point at which they were tested and listed. So for instance if you have one that says it is good for 600V, and you touch something that is 120V, you are fine, but if you touch 4160V, you cannot expect even that handle to protect you. If you take a Dollar Store screwdriver with a plastic handle but no voltage rating, then 120V might not conduct, but 480V? Maybe, maybe not! You just will have no way of knowing until it is too late.
 
Happy I don't have to do this any more. In the Army I used to have to test a 16 kV power supply for a radio amplifier.

Used a special cattle prod like probe for the DVM.

First clean the probe really well with a nice CFC based degreaser, then clean it again.
Stand on rubber mat while wearing special insulating shoes.
Have buddy stand by ready to hit the emergency off switch.
Touch probe to power supply contact.
Get tickled by something that felt like a spark plug wire or fence charger.
Clean probe a couple more times and try again because even fingerprints are conductive.

There's insulated and then there's insulated . . . :)

Even though I've tested my screw drivers, I don't really trust them.
 
DarylH said:
Happy I don't have to do this any more. In the Army I used to have to test a 16 kV power supply for a radio amplifier.

Used a special cattle prod like probe for the DVM.

First clean the probe really well with a nice CFC based degreaser, then clean it again.
Stand on rubber mat while wearing special insulating shoes.
Have buddy stand by ready to hit the emergency off switch.
Touch probe to power supply contact.
Get tickled by something that felt like a spark plug wire or fence charger.
Clean probe a couple more times and try again because even fingerprints are conductive.

There's insulated and then there's insulated . . . :)

Even though I've tested my screw drivers, I don't really trust them.
Click to expand...
This is a case where a combination of a good insulator (although of variable quality) and a grounded ring between that and the part of the handle that you hold would have been the ideal combination. :)
PS: A CFC-based degreaser will not necessarily do a good job on simple salts and other inorganic contaminants.
 
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petersonra said:
used to be pretty common to see black electrical tape wrapped around the shaft of screwdrivers being used by electricians.
Click to expand...

I remember doing that. I also remember wrapping an entire ratchet handle with rubber tape when told to check lugs in live panels. Good thing it wasn't a torque wrench. That would have meant more tape!
 
petersonra said:
used to be pretty common to see black electrical tape wrapped around the shaft of screwdrivers being used by electricians.
Click to expand...

And adjustable wrenches for tightening split bolts on service drop re-connects.
 
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