maintained exit light

[Scoby_Beasley]

Actually, even though its not really something of which to make thoughtless fun, there certainly is a very real effect where people take greater risks because they feel safe - in effect people drive (or any other activity for that matter) at constant percieved risk.

So if there is a hand rail by a deep hole, people lean on it, but if if no hand rail was fitted they would stay back from the abyss. So, adding a handrail that is badly fixed, is actually far more dangerous than none at all, as it encourages people to take a risk.
To that end I am opposed to things like power steering, that do not let you feel the car losing grip until it is too late, and it would not surprise me to find that people who know they have ABS drive either faster or closer together than those without, thus to an extent nullifying the initial safety advantage. As the driver of a car without, it certainly seems so.
In fact to make people act safely, you have to make them realise the potential danger - some drivers I suspect would only calm down if there was a big sharp spike in the steering wheel centre, but I digress slightly.
Similarly, safety interlocks and trips are only good, if they are not relied upon as an alternative to turning things off properly, otherwise they are less than a benefit.
I remember watching a friend dismantling an extractor fan, with it running 'because the safety switch will turn it off when the case is open' Except it didn't - there was no such switch, much to his disbelief, and he was left flailing with the fan whirring away like a demented gyroscope until the cable pulled out of its mountings. I put it down to a sheltered childhood (perhaps his parents never let him hurt himself with knives/matches or whatever, an essential part of my own learning process) and I must admit I was always cautious of his idea of 'safe' after that.

My thoughts entirely, you think YOU are safe and b******s to any one else

 

[jtaunton]

Vastly off-topic now, but has anyone ever been saved by a seatbelt in an aeroplane ?? Maybe it just makes your body easier to identify if you have a numbered seat strapped to it....

Or a lifejacket for that matter ?? How much petrol is wasted flying hundreds of these things all over the world.

 

[mapj1]

At the risk of having the thread peeled off by the mod and moved to general natter on safety/ risk assesments or otherwise, I suspect very few. Air crashes tend to be fatal, unless they are the kind where the aircraft hasn't taken off yet. To land a passanger aircraft on water is damn nigh impossible when its all working well, with a serious malfunction more so.

Having been involved in the design electronics for flight trials once, I can safely say I have never worked with a more risk averse bunch than flight safety officers. The idea of acceptable risk, i.e. that risk below which its more fruitful to put the effort into something else, had not really occurred to them. As a result you have to have a check that the safety catch is in place, and a further check that it has been checked correctly. The result is that the test electronics to be plugged into the plane which must not disintegrate into dangerous fragments until a G rating (10 I think) by which all humans are already dead is as a result it is about 10 times heavier than it need be.
However, because they cant see it, I can take a laptop and all sorts of heavy stuff and strap it into the seat beside me, as that is luggage. DOH!
This contrasts sharply with the nuclear chaps, who are happy to say that a leakage rate equal to pre-existing background radiation is OK, as it only doubles the risk, and means that you can't prove your cancer was caused by the their device or by natural radiation, as on the border the odds are exactly equal... so they are OK.

Some people are not objective about risk, and go into 'never again' mode after one accident so flukey that it will not happen again for ages. This makes us all jump hoops, and yet other, really quite risky things are done everyday. I remember hearing (somewhere) the anecdote that the H and S guy is the man who stops the machinist from using a drill bit, if the interlock on the guard on the drilling machine needs cleaning, but then stands on the platform to catch the train home and thinks nothing of it as the non-stop train before the one he wants passes through with nothing in the way to stop him falling in front of it..
I'm sure if cars were invented now, the idea of enough storing hydorcarbon fuel to fire the driver into space if burnt properly, in a single thin sheet metal tank, inches above the road, and passing through rubber pipes within inches of hot pipes and rotating parts, would be so horrific you'd never do it. But millions do, everyday, and most accidents are caused by something else.
Home cooking, causes food poisening up and down the land, but is not regulated anything at all like restaurants.
And then of course there is home wiring. But I dont want to go there right now.. you know my views.

 

[ban-all-sheds]

I'm sure if cars were invented now, the idea of enough storing hydorcarbon fuel to fire the driver into space if burnt properly, in a single thin sheet metal tank, inches above the road, and passing through rubber pipes within inches of hot pipes and rotating parts, would be so horrific you'd never do it.

And if salt did not exist, and was discovered and proposed as a food additive for flavour enhancement and preservation, it would never be approved - IIRC it fails every food safety test there is apart from being a carcinogen.

 

[bonebill]

Can you convert a non-maintained light to maintained or do you have to scrap the light and buy new ones which are maintained?

I don't think you can convert them.

Many moons ago, I had a summer job working in a place where they made emergency lighting. (In fact they mostly converted ordinary luminaires into emergency ones.)

If I recall correctly, you have a major difference because maintained lighting has to be able to run continuously, which is affects design factors such as how it deals with waste heat.

On the other hand, non-maintained lighting only ever gets to run for 30 minutes or so (or whatever the on-battery run time is) at a time, which is much easier to cater for.

One of the things they had was a temperature monitoring rig which they used to check new luminaire set-ups.

Funny thing was they tested ceiling luminaires on the bench, face-up, i.e. upside-down relative to normal fitting, where all the waste heat could easily escape by convection, and not as you would expect, the right way up, fitted flush in a ceiling where the waste heat would tend to get trapped by convection.

 

[crosser]

Hi,

My local village hall was paid a visit from Building Regs as we are currently having an extension built. He was not impressed to see that the emergency exit lights in the hall were non maintained (only on when power goes out) and we should have maintained lights. Can you convert a non-maintained light to maintained or do you have to scrap the light and buy new ones which are maintained?

I have opened one of them up and the incoming mains goes into 3 terminals of a 4 way connector block. I think the live is in the terminal labelled 'switch' and the 4th terminal which currently has nothing connected is labelled something like 'ch'. I forgot to write down what was on the connector block exactly so apologies for appearing stupid.

Any help gratefully received.

nick

Quick hello to everybody 1st Post.

BS 5266 states "To illuminate exit and safety signs required by the enforcing authority" so if he says they have to be maintained then so be it, it is generally good practice that all lights leading to a final exit or outside a final exit are maintained.

the option on your lights converting them to maintained it is possible on some lights to convert just by placing a link across terminals but it depends on who made them.

with regards to an earlier comment emergency lights have no relation to the fire alarm, they are purely there for in the event of mains failure the building isn't plunged into darkness, I have been called out to a customers regarding a fault on the emergency lights and the reported fault was when the fire alarm went off the emergency lights did'nt come on

regards

crosser

 

[plugwash]

On the other hand, non-maintained lighting only ever gets to run for 30 minutes or so (or whatever the on-battery run time is) at a time, which is much easier to cater for..

im my experinace emergency lights run for a LOT longer than thier specified run times in practice.

also i belive that many maintained lights run at higher power in mains mode than in battery mode.....