Warning Sign - Do Not Place Objects Here

Oh.. I missinterpreted 'BS' .
A safety barrier would be more use?
Or glue some pound coins to the floor in that area. Baaad kitty

Del

It's mounted on a moving trolley -

_{^{(Actually, you got BS dead right!)}}

Certainly thinking along the right lines, Vince.

This is what has been proposed to the customer:

the one im .llrc. has a hand , horizontal plane, being squished , like the fork lift ..sign,.. but yeah..

glad to be of help..

GA. A variation on that was for the team leader to have everyone in the area to sign a work sheet before you could qualify for that job or area. Sometimes included FME, as in this case, hazards, and other appropriate notices. The worksheet was kept with the chief engineers other logs. It was a bit of a pain when your job description changed (sometimes every day), but it worked fine. Oh yeah; Foreign Material Exclusion, or 'FME' is a bright orange sticker, about 1-1/4" x 4"

Some nice net curtains around the bit wot goes up and down, to protect the area beneath.
Del

The bit wot goes up and down also goes round and round ...

Just wondering... how about the possibility or putting a bellows-type sheath between the platform and top of the base? I'm thinking of something like what you see on an old time camera. It seems to me to be the best way of keeping foreign objects out of the system.

But then, some bureaucrat would come along and say the sheath needs to be permanently attached, or it would need a sign saying, "Do not remove sheath."

Bellows have been suggested - but rejected, partly because the tabletop rotates (and is pivoted eccentrically), and partly because there are connectors for two CCTV cameras (not visible in the photo - they're on the far side of the lifting column) which must be accessible.

There is also a requirement to minimize the amount of material near the tabletop, as the instrument response can be affected by radiation scatter.

'But then, some bureaucrat would come along and say the sheath needs to be permanently attached, or it would need a sign saying, "Do not remove sheath."'

- too true!

Second thoughts - red & white (prohibition) may be better, because the (yellow & black) hazard wouldn't be there unless & until the object was placed ...

Hello John,

Hope you are fine?

I found this site which seems to give full instructions on the latest danger signage. And it also seems ALL danger signs should be yellow and black. Lesser danger signs in orange.

Hope this helps

Please let me know.

bb

Hi, bb,

re. the colour of the sign, yellow & black would've been right if the danger was already present, but red & white are needed for prohibition.

e.g. if the minimum gap between the tabletop and the plinth was less than 300mm, a yellow sign with a triangle, saying "do not put your head in this area" () would've been appropriate (tho' the machine still wouldn't have been passed for safe use).

In this case, the gap can't be less than 300mm, so there is no hazard until someone piles a stack of books down there before putting their head on top of the pile and lowering the tabletop - hence red & white (with a circle) - DON'T put stuff here.

More details in The Health and Safety (Safety Signs and Signals) Regulations 1996.

Hello John,

Thank you for your return post.

I see you are probably more 'au fait' with the rules than me!..........

bb

Reading further, and finding the use for this machine, I recommend the orange and black FME sticker on it. Surround the area with yellow and purple rope and the same color signage for radiation areas. And a red flashing light while testing is underway.

Those colors may be the norm your side of the pond, but our colours are different - see my link in #14. I believe that the red/white, yellow/black, blue/white and green/white schemes are also used in the rest of Europe.

Roping off isn't needed - the system is installed in an 'exposure room' with a key exchange security lock. When the door is open, the only movement possible is table height adjustment, to enable the operator to align the instrument with the radiation beam. Wall and ceiling mounted lasers are used to give a cross-hair type reference to assist the operator. Table height is controlled by an up/down rocker switch on a pendant (which also carries an emergency stop button).

Once the instrument is at the correct height, the operator leaves the exposure area, locks the door and moves the door key to a keyswitch on the control unit, thereby enabling trolley movement (horizontal & rotary) and the shutter drive mechanism. When movement is enabled, there is a 10-second audible alarm, and a continuous flashing blue xenon beacon in the exposure area.

When an exposure is requested, there is a 10-second interval with audible and visual warnings that an exposure is imminent. When the shutter is open, there are red warning lights on in the exposure area, the control area and in the corridor outside. While the shutter is open, the door key is trapped in the locking switch.

There is also an independent radiation monitor, with an audible alarm, which is on when radiation is present.

I've been designing, testing, commissioning and maintaining these systems for 25 - 30 years. Every few years, the regs get more stringent, and upgrades have to be made. Eventually it gets to the stage where an old system is no longer 'fixable' (just in terms of conforming to the current standards) and has to be ripped out & replaced.

Can you post a link to that site, please?

Hello John,

I have had problems with my connection dropping today, so am finding it hard to sort out whom I should be answering and in what order. So sorry I this has not been answered or is inappropriate, but, were you referring to me when you asked for the site reference?

I thought I had pasted it but I know the ISP has been dropping sometimes just as I go to send, so sorry OK.

This is the sight. And it is not at all clear to me what type or colour of sign you should use. But as you have bought signs before you should know and understand this page fine.:

http://www.hse.gov.uk/pubns/indg184.htm

bb

Hello again John,

I looked at a whole lot of sign sites and hope I sent the correct one to you. Sorry if it is no help. Felling kinda flustered this morning as my ISP drops once again.

bb

If you cannot find off the shelf sign that you need you can make your own with a specialist label printer - go to this site: http://www.puresafety.co.uk and put 'Label Printer' in the search window and you will see what is available. You get a variety of desk-top and hand held models and all colours and sizes of tape for them - then arrange what symbols and words you want to put on the label and you have what you need.

Thanks for the tip - but we only need a handful of such 'specials' a year, so we use a service where you can design your own label on-line, and they'll print it for you.

Hello John,

Just being nosey, what is this used for?

bb

Hi, bb,

This is part of a system for calibrating radiation measuring instruments.

Out of picture to the right is a source exposure unit, which allows a radioactive source to be selected (from several available activities & nuclides). A shutter can then be opened to project a collimated beam of radiation parallel to the track.

The instrument to be calibrated is placed on the table, and the radiation doserate can be adjusted by varying the distance between the instrument & the source (hence the track).

BTW - this photo was taken after factory acceptance testing & just before loading onto the truck for delivery - hence the scruffy workshop rather than pristine lab background .

Signs are for ignoring by idiots. Mount table on load cell. Use info from load cell to stop downward movement and sound an alarm if the table encounters an obstruction.

Regards,

Keywalker

p.s. and yes safety does cost extra.

i tend to agree w/ you over , signs. after the 1st couple of times i think they , the signs, are largely ignored by the workforce. unless placed in such a manor, where you might have to move the sign to do the task. unless , if you have been a example of the need for the sign.

somehow i think , the technicians in this case might be a little more diligent.

but the temptation to use this surface as a table during the alignment procedure , does exist...

possibly the only " cure " is the brifing given when installing the device...

2 cent

A safety-rated load cell ???

We had initially designed in safety edges between the tabletop and the plinth, but this was rejected as an unnecessary over-complication. The system is used only by fully-trained lab staff - typically only 3 or 4 people (including the department head) are permitted to use it. To get anywhere near inflicting harm on either himself or his colleague would have to be a deliberate act - or the act of a madman.

• The tabletop moves at about 1 metre per minute
• The rocker switch on the control pendant must be held pressed to enable movement
• The pendant has an emergency stop pushbutton, which is part of the dual input circuit of a monitoring safety relay - pressing the e-stop removes power from all actuators
• There is another e-stop on the trolley plinth

So, two possible(?) scenarios:

1. The solo idiot, who wants to watch the underside of the instrument while he lower it onto his face. Limbo-ing with his head on the nasty, hard ally plinth while grasping the pendant and pressing DOWN becomes uncomfortable, so he piles up some well-thumbed copies of 'Radiation Metrology Weekly' on the plinth as a pillow. He then proceeds to break his nose by resuming his previous position, pressing the switch and forgetting to let go until the pain becomes unbearable.

2. The pair of idiots. One stumbles in after a long lunchtime session in the local hostelry, trips over his own feet and knocks himself out with a glancing blow to the head from the 750kg (motionless) source container, coming to rest with his head balanced on the pressure/temperature/humidity monitor which someone had carelessly left under the tabletop. Meanwhile the second idiot is in deep conversation with his wife on his mobile phone, trying to explain that it was his drunken colleague who had been feeling up the barmaid, causing them to be ejected from the hostelry, and forgetting that he's holding the DOWN switch on the table control pendant.

I ask you.

Right! Load cell was just a brain fart i threw out in a moment of delusions of grandeur. Not really practical in a monetary sense for the problem presented. Please see my previous post further down line.

What about a hologram of some or other animal eating a body part of the previous sinner.

Here is a note placed by one of our clever workers.

Don't bother here - Trespassers will be prostituted.

I had another thought (danger ahead). Put a windsheild wiper type of arm to clear any obstruction before downward motion can be initiated. If the wiper can't sweep clear then no downward motion.

You could put op a laser sensor screen(area) witch triggers a horn, or a lamp, or a scary warning. (or all of these above)

Like the OMRON OS3101

Yea, we went through light curtains/laser scanners/safety edges and all the rest for the whole system (trolley horizontal & rotational, as well as vertical movement).

The conclusion was that gains in throughput made by permitting access to the room while the system could move were outweighed by the increased design complexity, the capital cost of the safety systems and the maintenance costs. The only exception was the vertical movement of the table necessary to align the instrument with the radiation beam axis.

So it was decided to disable all movements while anyone was in the room - except the table height adjustment. We are making this as safe as reasonably possible.

Your suggestion of the OMRON OS3101 or similar systems would have required four scanners (or at least three!) adequately to protect the area in question. They are not cheap.

So it comes down to a balance of safety, cost and usability.

If safety standards were as stringent in the domestic kitchen as in the 'workplace', knives, forks, food processors, coffee makers, hobs, ovens etc. would all have to go.

then i would suggest to put some wire around it, with 12 volt attached to it, to scare away unwanted persons (normally used to keep animals in their grazing area in Holland we call it "schrikdraad" (startle-wire)).

Switches are cheap. Would it be possible to hinge the table and install a switch to halt downward movement if the circuit is broken? The table would have to remain in contact with the switch to operate. An obstruction would lift the table slightly and open switch.

If you can sacrifice a little but of downward movement. Build a slight tefflon dome on the surface then when someone tries to put something there it will slide off.

Hi scotchdrkr,

This is a very good idea! It is used one machines sometimes where it is a danger to the electric or similar, you know? The easiest and most sensible thing yet!

bb

Thanks to all for the suggestions. FYI, this is the sign that our conformance consultant and our customer have mutually agreed on: