cheap multimeter

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Warning, Graphic: Fatal electric shock.  On the extreme but a lesson, you can only make such a mistake once.

My grandfather was killed like that at Stafford in the UK. He was trying to replace an overhead light unit whilst working on a track laying machine. It was very damp on the morning he was working which unfortunately made it very easy for the 25kV to get him

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If I stand on a wooden stool wearing rubber soles, rubber (or rubberized) gloves and safety glasses, what is the likelyhood of being electrocuted, injured or dying when operating on a live domestic circuit (say changing a light rose or something like that).

I have done this on several occasions using an insulated screwdriver and multimeter, and the biggest concern was a wire piercing one of the gloves.

To me it seems that the biggest risk is from falling off the stool and landing on the screwdriver or something to that effect. The likelyhood of both gloves being pierced at the same time and closing a "dangerous" circuit seems highly unlikely, and if one of the gloves were to be pierced by a live wire the shock would be localized and would at best cause me to lose my balance -- and gravity would disconnect from the wire.

I don't do this routinely and I have resorted to doing this to avoid certain risks and inconveniences that arise when working alone and having to distance myself from the exposed wires, in order to disconnect and reconnect the mains.

.o:0|O|0:o.

Many an electricians lifes have been saved because they were working on a ladder.  They usually got in trouble with the neutral wire. Could not let go until their legs gave out & they fell.  The impact can even restart a heart.  The ladder can work both for you or against you.

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Here in America we call the analog meter shown in this thread a VOM (Volt-Ohm Meter).

The situations to avoid with a meter:

1. Have the meter in ohms instead of volts and touch the leads to a voltage source.  The better meters will just beep at you now ( hopefully ).

2. Have the meter leads in the current jacks & touch the leads to a voltage source.  This is the most dangerous thing you can do.  It is also a very easy thing to do.  This error can be last for an industral electrician, as it may result in an arc blast. 

Always double check your setting before touching a voltage source.   
Return the meter to the standard voltage measurement configuration after a current measurement. 

When probing mains voltages always wear a leather work or driving glove. Any glove is better than your bare hand. Unless you own chain mail !! This will greatly limit any shock you could receive from the mains.  Safety glasses are a good idea too.

Oh, yes never measure the electric fence with your meter !

Just a few simple things to know, so you an your meter can have a long & happy life.

Here is a link to the 10 Dumb Things Smart People Do When Testing Electricity.
http://support.fluke.com/find-sales/Download/Asset/2071940_6003_ENG_B_W.PDF

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There are simply rules to follow for each CAT rating you are exposed too.  One simple safety item for home work, which is CAT 3 or lower, is also wear insulating rubber soled footwear, not leather and wear cotton clothes, don't do it naked or bare feet! 

http://www.ien.com/article/selecting-right-amount/7594

The reason is the spark, is usually high intensity but short duration, and clothing alone can provide protection against the flash.  Shoe insulation protects the user from electrocution.  CAT 4 level issues are best left for a certified professional.

Plastic eye glasses or eye protection is at least for CAT 3, also you should wear it whenever power tools are used.

There are other safety items you can do that aren't part of CAT ratings, but the one-hand rule never hurts.  If you probe something you aren't sure, don't hold both probe leads, but connect one with a alligator, and probe with one hand, this way the full circuit is not with you but only on the test gear.

Now, given all this extra stuff to think about, the last thing you need to worry about is if you are using a 'iffy' cheapo meter, just how good it is.  You don't want to do the one-hand rule and then grasp the meter with the free hand, not knowing the ground is somehow exposed in one way or another or poorly insulated.

[Kiriakos-GR]

Oh, yes never measure the electric fence with your meter !

 
Some one very recently did just that , and now he is with a dead DMM ...

The poor fella was a kid in a farm or something, and came in the forum for instructions,
about repairing it.
The poor DMM fried it self ..  and it was just in the second testing measurement ..
The first was an small battery.

[SG-1]

Oh, yes never measure the electric fence with your meter !

 
Some one very recently did just that , and now he is with a dead DMM ...

The poor fella was a kid in a farm or something, and came in the forum for instructions,
about repairing it.
The poor DMM fried it self ..  and it was just in the second testing measurement ..
The first was an small battery.

I had a friend who did this also many years ago.  The meter was fried.