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-   -   Radio Servicing Causing Death (https://www.vintage-radio.net/forum/showthread.php?t=26340)

Rejectostat 17th Mar 2008 2:26 pm

Radio Servicing Causing Death
 
I have just been reading the thread relating to safety precautions whilst servicing vintage radios: (Here: https://www.vintage-radio.net/forum/...ad.php?t=25275)

It set me wondering, does any Forum member know of anyone who has actually been killed by a shock whilst servicing a vintage radio? If so, what were the circumstances? Otherwise, is anyone known to have suffered very serious injury? I am thinking not only of now in the vintage world, but also in the past when it was a day to day activity in a service repair workshop. I have heard of people being killed whilst servicing televisions, but I think we all know the acute risks there so I am more interested in the radio side. Whilst I realise this subject is a touch macabre, sometimes sad stories and actual examples can remind us all how essential it is to take care whilst working on these old receivers.

ianj 17th Mar 2008 2:54 pm

Re: Radio Servicing Causing Death
 
I am suprised, being an ex-electrician, I have a few "belts" under my belt, so to speak! But, there you are, 220-240 v kills................................ianj

Steve_P 17th Mar 2008 3:08 pm

Re: Radio Servicing Causing Death
 
It's volts that jolts but amps that kills. Also, always keep one hand in your pocket when you're working on live stuff.

I once heard of somebody really badly hurt (burned) when he fell back and reached out for the nearest item - an earthed busbar! He was stuck for a while, then broke the circuit and fell. His hands were burnt off and he's now in a wheelchair.

That's worse than dying in my view....

Cheers,

Steve P.

dave walsh 17th Mar 2008 3:38 pm

Re: Radio Servicing Causing Death
 
Slightly OT Steve but I met a bloke on the Burns Unit at Wythenshawe Hospital in the early seventies. A staff electrician there, he was servicing some sort of Carbon Arc device [you know electro magnet regulates the spark as the carbon rod burns down] bright light, high power job. Thinking the interlock was off he managed to put a hand on each electrode [somehow-his words]. He said that he could see his fingers charring but of course, couldn't let go. Only survived by ramming his legs so hard the metal mountings tore away from the wall. I think he had three fingers left on one hand and two on the other but they were still being re-built.

Re the servicing deaths issue, I can't ever recall one in a workplace re servicing a TV or a Radio but I am sure that this will have happened. March's Television Mag has a good near miss for example. Likewise the warning tone of Amateur Radio Manuals suggests that domestic fatalities had occurred, although the major problem there at one time seemed to be with whips and overhead power lines-especially in the days of portable operation on 160/80 metres! Overall you do get the impression that the Service Workshop accident rate must have been very low, either by luck or by caution. On the Amateur front, I've never seen an obit in the RSGB Mag or SW Mag that referred to an electrical accident. Dave

kibble 17th Mar 2008 4:23 pm

Re: Radio Servicing Causing Death
 
Back in the early 70's a colleague of mine was repairing a transistor stereo amplifier. He leaned over the amp on the bench just as an electrolytic capacitor launched its self free from the PCB & hit him in the adams apple. The noise was very loud which caused several engineers to investigate. The injured engineer was quickly discovered on the floor unconscious, not breathing. Fortunately after a short period of artificial respiration he resumed breathing & gained consciousness. This was a very sobering experience which for me squashed the myth that working with transistors & low voltages is safe.

murphyv310 17th Mar 2008 5:08 pm

Re: Radio Servicing Causing Death
 
Hello.
In my 37 years in the trade I have never heard of a death repairing a Radio or TV.
I have though heard of a collegue with one of the nationals losing his life working on a microwave oven (just as bad as mains derived EHT)
Two other instances were, (1) in British Relay one of the MSE's were working on a live chassis set on raw mains with the plug in wrongly, He had one hand on chassis and went to pick up the aerial plug and got strung on, he was pulled off with a brush shaft! He was Ok although a bit shaken and a nasty burn on his hand.
(2) in Clydesdale a newly time served lad was working on a G8 with high EHT the RBM eht tester was connected to the CRT but the safety cap was missing from the connector on the top of the EHT meter, he leaned over the tester and got a very severe burn on his stomach as he too was touching chassis at the time, he was off work for a good few weeks.

Any engineer is responsible for his own safety and should not use faulty equipment, the MSE in British Relay should really have known better as the aerial system was earthed, and he should have been using the isolation transformer.

Trevor

Heatercathodeshort 17th Mar 2008 7:40 pm

Re: Radio Servicing Causing Death
 
In 1961 when I was first working in a repair workshop an older engineer showed me a split that ran from the nail of his thumb down to the base, about 2" long. He had aquired this while servicing an early projection receiver in the 50's. It appears the eht connector sprang off and landed on his thumb. He admitted that he was testing for eht and had removed the tight fitting connector and not replaced it correctly.....A slight fugus grew in the 'crack' in his thumb for the remainder of his life.
A word of warning. If you have fitted an angled aluminium strip to the edge of your workbench to prevent damage to the wood, remove it! Think about it...
Regards, John.
Nasty.....Regards, John.

Steve_P 17th Mar 2008 7:45 pm

Re: Radio Servicing Causing Death
 
I wonder if anyone has been killed by the wife....

Cheers,

Steve P.

Skywave 17th Mar 2008 7:52 pm

Re: Radio Servicing Causing Death
 
In the early '60's, I knew two men who quit working for a local business in its TV / radio repair workshop & set up on their own. One did radios, the other - (Vic by name; ex - RAF radar tech.) did the TV's. I never did find out, exactly, what it was he was working on, but I do know from his mate that said TV engineer received such a belt - it is believed / suspected - from the EHT section of an old TV that he was working on (mains-derived EHT?) that upon the recoil, he banged his head on an overhead wooden beam supporting the (low) roof. The recoil to this, in turn, threw him back over the open chassis. His work-mate called an ambulance - but, alas - he was found dead when it arrived.

It was a great shock & tragedy to all who knew him. He was a very friendly, polite & helpful gent. The fact that he was over 6 ft. tall probably didn't help, either.

Al / Skywave.

Skywave 17th Mar 2008 7:59 pm

Re: Radio Servicing Causing Death
 
Quote:

Originally Posted by kibble (Post 168794)
He leaned over the amp on the bench just as an electrolytic capacitor launched its self free from the PCB & hit him in the adams apple.

I know; I know >((.

Happened to me in the early '70's. HV PSU for a VHF transmitter. Fortunately, the cap. just missed my right eye. 8-o I've been very generous with my chosen d.c. voltage ratings of electrolytics ever since.

Al / Skywave.

Steve_P 17th Mar 2008 8:02 pm

Re: Radio Servicing Causing Death
 
Before this decomes a 'Let's swap awful stories' thread, and I am guilty here too, do you (and your Family) know what to do when an Electric Shock leaves someone unconcious?

http://www.firstaid.ie/tip_electric_shock.htm

http://www.pat-testing.info/electric-shock.htm

http://www.safetyfirstaid.co.uk/Prod...ent-Guide.aspx

Cheers,

Steve P

tellyman 17th Mar 2008 10:20 pm

Re: Radio Servicing Causing Death
 
This thread conjures up a lot of might have beens. I can't remember a workshop where I worked in my early career that had any form of mains isolation, transformers ect. In fact the only "safety " precautions I can remember being taken were to make sure the workbenches did not have the earth connection fitted.
But then again I think the first thing I was taught was all about safety. Remember in those days most sets had their chassis connected to neutral mains, that was if the plug was correctly wired. Hard to be sure if the set was fitted with a bayonet connector as many were. My first tool was a neon screwdriver for this very purpose.
However I can't remember anyone being seriously injured, probably because we were made very aware of possible consequences.

Mersey_Swimmer 17th Mar 2008 10:38 pm

Re: Radio Servicing Causing Death
 
I must admit that despite growing up with 50s and 60s radios (valve and transistor) I've never known of anyone being electrocuted. I've known many TV engineers take a belt, as I have myself. If I remember correctly, early colour TV EHT supplies were potentially lethal as they were capable of delivering 5mA or more - as well as the PD500 X-raying you! I understand that modern CTV line-output stages are far more forgiving - indeed the EHT in my little 5" portable colour set is a mere 7kV.

I sometimes wonder how I'm still here as when I were but a tadpole my Dad would only let me have low voltage in my shed - 20VAC fed down bell wire from a transformer in my bedroom. However Dad didn't realise that transformers work both ways, and I had a selection of....er.......interesting voltages available for various experiments (some of which involved about 3,000uF-worth of old telly smoothers wired in parallel!) that would have a contemporary H&S freak gibbering in a corner.

I've always understood that in industrial settings explosion is much greater risk than electrocution and although when working with industrial electronics the highest voltage I've had to deal with is 415v, it's been at very high currents (>1000A). Drop a spanner across busbars with that sort of current available and the resulting blast could well kill - the protection gear (fuses and/or breakers) may not act fast enough to save you.

Microwaves are an obvious risk with around 2kV being available at hundreds of milliamps. However high-powered valve amplifiers deserve respect as their HT suppiles can be anything up to 1kV.

I think I'll stick to stuff powered by PP9s ;)

Pete

mickjjo 17th Mar 2008 11:01 pm

Re: Radio Servicing Causing Death
 
There was a sad case in the mid-fifties, as told by Gerry Wells in his autobiography "Obsession" on page 78. Gerry's former Red Bank School instructor, Reg Yates was killed by accidentaly touching the mains derived EHT on a Pye B16T TV set, A verdict of accidental death by electrocution was recorded, perhaps the first case of its kind :o.

Regards, Mick.

tellyman 17th Mar 2008 11:05 pm

Re: Radio Servicing Causing Death
 
Just another thought, anyone remember the old trade test colour film about electrical safety? Can't recall the title, but I remember the words, switch off, isolate ,dump, earth.

Mersey_Swimmer 17th Mar 2008 11:33 pm

Re: Radio Servicing Causing Death
 
Quote:

Originally Posted by tellyman (Post 168884)
Just another thought, anyone remember the old trade test colour film about electrical safety? Can't recall the title, but I remember the words, switch off, isolate ,dump, earth.

Yes, I remember it from when I worked at British Relay back in 1968.

It was something to do with high-energy physics involving a large capacitor charged to a high voltage. Due to a wiring error the arrangement to discharge the cap was on the wrong side of the circuit, leaving a supposedly "safe" circuit anything but. The result was a hefty explosion in the face of a scientist making adjustments to a circuit he assumed dead.

The acronym was of course "SIDE", and the "dump" referred to dumping the charge on any capacitors present. Just as an aside, a long length of mains cable can store enough charge to inflict a shock should it be disconnected at or near the peak in the mains waveform. Particularly on 415v supplies.

Pete

bc312 17th Mar 2008 11:39 pm

Re: Radio Servicing Causing Death
 
The film was titled "On The Safe Side", and was produced by the UK Atomic Energy Authority. Men in white coats playing with pretty dangerous looking stuff, and the constant mnemonic warning - SIDE.

Steve_P 17th Mar 2008 11:51 pm

Re: Radio Servicing Causing Death
 
Safety Isolate Dump Earth !

I have that film! That bloke was so close to a sticky end...

Cheers,

Steve P.

GMB 17th Mar 2008 11:56 pm

Re: Radio Servicing Causing Death
 
Quote:

Just as an aside, a long length of mains cable can store enough charge
It's true! I measured it for 2.5mm2 cable as about 100pf/m and for 10mm2 as 200pF/m - so quite modest cable runs are well into the nF range and so are comparable with emc filters.

I remember the SIDE film too. Obviously well made since it seems to be well remembered.

ppppenguin 18th Mar 2008 8:45 am

Re: Radio Servicing Causing Death
 
One of my favourite BBC2 trade test films. I have a poor quality VHS copy somewhere. SIDE: Switch off Isolate Dump Earth. Nice BVWS DVD would be a selection of these films but that's a different topic.

Just to show that even very low voltages can be dangerous I know of somebody who burnt his wrist badly by getting a metal watch strap caught between the +ve terminal of a car battery and the bodywork.

In many cases the actual electrical effects of a shock are merely unpleasant. It's falling off the ladder or banging your head that's dangerous.


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