Trying to get a streetlight shielded, not going to well.

[Carbon Brush]

Methinks it is time to show the council the error of their ways. Name and shame?

Another approach is to demonstrate by calculation that your proposed baffle presents insignificant additional forces on the lamp post.

I'm not a structural engineer, or civil engineer. But I'm sure someone on SGL is knowledgable in these areas.

I just did what we all do when faced with the unknown. Ask Mr Google.

Here is one answer......

Reference https://www.physicsforums.com/threads/calculating-wind-pressure-against-a-rigid-wall.322667/

Another approach is to calculate the power in the wind. P = (1/2)ρAv3 where ρ is air density, A = area, and v = wind velocity.

Since power is force times velocity, the force is F = P/v = (1/2)ρAv2

This assumes the air velocity is zero after hitting the wall, which obviously cannot be true because there would be a big localized increase in density and pressure.

So there has to be a factor like the Betz factor β for wind turbines.

So the force is now F = P/v = (1/2)βρAv2 So for a density of 1.2 kg/m3, A = 1 m2, and v= 10 m/sec, F = 60β Kg m/sec2 = 60β Newtons on a 1 m2 area.

Putting this into something more like English. I will stick with a metric baffle size, but express wind speed in a more understandable MPH.

A 1 metre square baffle is very big. A 2metre long x 0.5metre wide (same wind load) is still quite big.

I think a realsitic baffle may be smaller and so have less wind loading. But I will stick with 1 metre square for the calculation.

I will also assume that air is fully stopped by the baffle, so will not apply a Betz factor which results in lower loading.

I have no idea what a reasonable Betz factor would be.

50MPH wind speed results in about 25Kg (55lb) pushing against the post.

This is assuming the wind is directly behind the baffle. Any other direction gives a lower force.

This is the sort of speed where we get warnings about fence panels, trees and slates.

75MPH wind results in about 100Kg (126lb) against the post.

A big number. But not often encountered in mainland UK. Storm stats anyone?

A definite 'slates off' wind.

These numbers are worst case. When a realistic smaller baffle is used, and the Betz factor is applied by some knowledgable person, they can be reduced.

I don't know about forces acting on the round section post from the wind. But if I assume 200mm diameter and 8 metres high, that comes out to 1.6 sq metres.

A bigger wind area than the baffle.

Now a really clever idea would be to make the baffle bend or fold in a strong wind.

After all, you aren't going to have the scope out when a gale is blowing.

Neither will you be sitting in the garden.

Time for someone (preferably with more letters after their name than in their name)  to show the errors in my calculations and present calculations that the jobsworths at the council cannot argue with.

Hope this helps. David.

Another approach is to calculate the power in the wind. P = (1/2)ρAv3 where ρ is air density, A = area, and v = wind velocity. Since power is force times velocity, the force is F = P/v = (1/2)ρAv2 This assumes the air velocity is zero after hitting the wall, which obviously cannot be true because there would be a big localized increase in density and pressure. So there has to be a factor like the Betz factor β for wind turbines. So the force is now F = P/v = (1/2)βρAv2 So for a density of 1.2 kg/m3, A = 1 m2, and v= 10 m/sec, F = 60β Kg m/sec2 = 60β Newtons on a 1 m2 area

Reference https://www.physicsforums.com/threads/calculating-wind-pressure-against-a-rigid-wall.322667/

Another approach is to calculate the power in the wind. P = (1/2)ρAv3 where ρ is air density, A = area, and v = wind velocity. Since power is force times velocity, the force is F = P/v = (1/2)ρAv2 This assumes the air velocity is zero after hitting the wall, which obviously cannot be true because there would be a big localized increase in density and pressure. So there has to be a factor like the Betz factor β for wind turbines. So the force is now F = P/v = (1/2)βρAv2 So for a density of 1.2 kg/m3, A = 1 m2, and v= 10 m/sec, F = 60β Kg m/sec2 = 60β Newtons on a 1 m2 area

Reference https://www.physicsforums.com/threads/calculating-wind-pressure-against-a-rigid-wall.322667/

[Carbon Brush]

I have just looked again at your photo of the offending lamp post and a brilliant (?) idea jumped into my head.

Ask the council if a pulley, with a rope threaded through, can be fitted to the top of the lamp post.

Get ourself off to the local boatyard. OK maybe not so local in Staffs.

Buy a large triangular yacht sail, along with the bits and pieces to fix it.

I think they are called lanyards, mainbraces, turnbuckles and cleats, and other odd names.

When not needed, keep the sail rolled up on the garden wall. Like when a yacht is not going anywhere.

On a clear night, hoist the sail, using the rope and pulley.

At the end of the night, lower it.

Job done! No structural loading issues. No permanent fixtures (except a small pulley).

If the council won't agree, then erect a flagpole in your garden just behind the lamp and use the same approach.

At non-astro times, hoist various flags, according to England/Scotland/Wales saints days, football tournaments, olympics, Christmas, etc. This will effectively disguise your true primary purpose for the pole.

This sounds more fun than structural calculations.

If the council ask for structural calculations for your flagpole, just buy a lampost instead!

[A40farinagolf]

Not sure if this has been mentioned before but some baffles / deflectors are fitted inside the glass bulb protector so wind loading is not an issue.

Painted surfaces also prevent light transmission in unwanted directions therefore adding virtually no additional weight either.

[happy-kat]

Yes mentioned earlier, my worst lamp post has had internal baffles added look like they weigh about 25grams they are that thin, they were going to paint, but when I got home it had baffles instead.

[Stub Mandrel]

> Now a really clever idea would be to make the baffle bend or fold in a strong wind.

After all, you aren't going to have the scope out when a gale is blowing.

Neither will you be sitting in the garden.

A Baffle could be hinged, with a magnetic catch to stop it banging about in light winds and a rubber bumper to stop it making noise in light winds.

[happy-kat]

The baffles are fitted inside the head light unit so not exposed to any environmental factors. I have not seen any external baffles / shields.

[Robp]

Cheers all for the replies but it seems that not even internal baffles or paint are a go:

I mentioned in my initial email that the authority acknowledge that there will be an opinion that an amount of stray light may affect adjacent properties from either, the back, side or front of the lantern. It is not possible to restrict this light in all its aspects without affecting the light output onto the highway. With regard to your suggestion to fit internal baffles or block the sides and back with paint. To make any noticeable difference, so much of the lantern bowl would need to be blanked out it would not be acceptable as it would affect the light output onto the highway.

On very rare occasions, a resolution is explored if a resident, who unfortunately suffers from a medical condition that is exaggerated by the light emitted from a street light. In these instances, we would require a note from the appropriate medical practitioner explaining the condition and how reduced lighting levels from a street light could ease their symptoms.

Another consideration regarding mitigating measures is ongoing maintenance liability, including any associated additional costs incurred. I’m sure you have seen on the news the squeeze on local government funding. We are no exception, therefore all requests are not just viewed from a practical point of view, but also financially.

I think it all boils down to the last sentance to be honest, money.

[Stub Mandrel]

There are an awful lot of Staffordshire residents on this forum.

Perhaps we should all put in requests to the same department. We had to buy a blackout blind for our bedroom and the overspill from nearby lights into our property is huge.

[Carbon Brush]

There are an awful lot of Staffordshire residents on this forum.

Perhaps we should all put in requests to the same department. We had to buy a blackout blind for our bedroom and the overspill from nearby lights into our property is huge.

Why not all you make an application to the council to buy and fit blackout blinds or baffles? Give them the option!

Surely the need for blackout blinds means light (money) wasted?

OK rant over. I hope you do get support from other Staffs residents, otherwise your rejection could be taken as a precedent.

[Robp]

Stub Mandrel: I think that you would have a better case than me as the light doesn't impact our sleep.

Apparently being able to use your garden in the evening isn't a concern for Staffordshire council, its just an acceptable part of lighting the highway to them

David Valentine: I think this is already a policy in place by the looks of it. I would guess that if it doesn't impact sleep they will just say no.

[DaveS]

Do you have anyone higher you can appeal to? the Mayor? Your MP? It looks like you have been unfortunate enough to have come up against what C. Northcote Parkinson called the "Abominable No-Man" someone who says "no" because if he said "yes" then he might actually have to *do* something.

[Stub Mandrel]

This is the view from my study window. Half of the back garden is lit up by light from this 'standard' shining on a large tree! I also have a container park to the north that is lit up like a football stadium.

The tree partly shields that lamp from the bedroom window, but the next light to the north shines on it.

I shall send the picture to the Highways Agency - it's a trunk road - and ask them what they can do about it, and demanding that residents needs are taken into account if they fit LED lighting. every single house along our section of road must have more or less the same issue.

[happy-kat]

That does not look very directional at all, more going sideways then directly down.

[Stub Mandrel]

I think they are just a glass bowl with the lamp below the level of the steel casing on top and no attempt to control overspill.

[barkis]

Hi Rob,

  I sympathise with your problem. Some Councils are more amenable than others, so you must have one that isn't prepared to 

help you.

What you mustn't do, is pay any attention to silly suggestions delivered here, that may be breaking the law. That will only get you into trouble, 

and probably a fine of no small amount. The person  who's advice you might have taken, certainly wouldn't pay it for you, so Ignore all negative suggestions.

We do have a CoC ruling about such  suggestions, and members ought to be careful about it.

Is there no way you can screen the lamp yourself from within your own property?

I am thinking of a large Tarp that  are quite cheap to purchase. If that was suspended from  two  posts, each with tripod feet, of sufficient height to block out the glare.

It would be easily taken down after use, and stored away, the sheet rolled up around the posts.

Windy nights would preclude you from using it of course, but you probably wouldn't use the scope either under those conditions.

Just a suggestion, it might not even be practical for you to adopt that solution.

Best Wishes.

Ron.

[glowjet]

Hi Rob, I was involved in street lighting with my city council for many years. from your photo it looks to me like a dual carriageway, as you say a Trunk Road, lit from a central reservation with fairly old lanterns, mounted on what appears to be old twin arm 12meter concrete standards. The light spillage is very evident, lighting up the night sky as well as the surrounding countryside. As you say this is controlled by the Highways agency.

 Your letter form the lighting  engineer, IMHO, is nothing more than an attempt to fob you off. As the OP in thread # 28 pointed out, shielding can be carried out from inside the lantern head, something my old authority did on many occasions in the past.  One solution is to provide one of the more modern lantern heads, that directs the light downward, onto the centre of the carriageway at the same time reducing light spillage to an absolute minimum. I am not familiar with these, as I retired some years ago, but I would imagine the Agency will plead the expenditure card, as a reason for not upgrading the light. You have recourse to take this to the Ombudsman as  last resort and I wish you well.

Having looked at the photo again, could you not mount two 2" alloy poles, (expensive, unless you can find scrap, or use steel) sunk into the ground, near the trees, either side of your path, with appropriate fixed pulleys and cords and blackout sheet, which you can erect to provide shade ? best of luck

[Carbon Brush]

Slightly off topic. But slightly relevant.

Today I was in the car park of a B&Q store. It was a bit windy. Perhaps 20-25mph gusts.

A fairly regular metallic clanging drew my attention. The noise was coming from a car park lamp post.

On closer inspection, the post was oscillating in the wind.

The twin lamp head was almost stationary. But the post vibrated like a guitar string.

About 25mm by my rough estimate in the middle.

The noise presumably being the internal cables banging against the post.

I'm no metallurgist. In fact I can hardly spell the word. Neither am I a structural engineer.

But I always thought that repeated oscillations like this on a long circular section could eventually result in structural failure.

I would like to think that 'proper' street lights are a bit stronger.

[Stub Mandrel]

A long steel column should be fine as long as the movements don't take it past its elastic limit. An aluminium pole would be more prone to metal fatigue from regular flexing, depending on the alloy.

[Robp]

Barkis:

Thank you for the support and I will of course not be breaking the law anytime soon.

Your suggestion to make a removable shade is probably the route I will end up taking but there are still a few options for me to explore with the council that I am going to take first.

Glowjet:

I think you have confused my lighting problem with Stub Mandrels lighting problem? The streetlight I have an issue with backs onto the side of my garden and it is on a crescent .

The last correspondence I received from the Principal Lighting Engineer did include two options for me to escalate to, both were addresses to write to (no Email address or phone number!). These were the Access manager for Staffordshire County Council and the Information Commissioner based in Cheshire. Personally I think there just making it hard for people to escalate things as nowadays most people would just leave this where it is and wouldn't bother to write a letter to either of these. An Email address is much more accessible.

For my next steps I am considering a few options but will not be continuing with this until after Christmas.

1. I'm going to ask for / try to find Email addresses for the two escalation points I have been provided. If unsuccessful I will forward on letters.
2. I'm going to raise a complaint with the council regarding the street light and the shielding decision.
3. I'm going to start a correspondence with my local councilor about the matter.
4. I was speaking with my neighbor about this and they have offered to start there own investigation into getting it shielded. Hopefully it would get assigned to someone different and perhaps have more success.
5. If all else fails, the Ombudsman would be my final port of call.

Thanks for all your messages, suggestions and support. I never thought it would be this hard to get a streetlight shielded

[Carbon Brush]

Rob, I wish you all the best for your ongoing battle. I don't think battle is too strong a word to use. It ought to have been a simple request.

Please keep SGL posted. This is a potential problem for many members. Anything that you learn from sorting out 'your' lamp could be used by others.

Have a great Christmas.

David.

[Stub Mandrel]

window.jpg

The tree partly shields that lamp from the bedroom window, but the next light to the north shines on it.

I shall send the picture to the Highways Agency - it's a trunk road - and ask them what they can do about it, and demanding that residents needs are taken into account if they fit LED lighting. every single house along our section of road must have more or less the same issue.

Well I've had a pretty good response from the Highways Agency's contractors, best bit of news is that we will be getting new units some time. I'm sure LEDs will be an improvement as there is a constant yellow aura all along the length of the road north and south.

The existing lighting equipment is old and it is approaching the end of its design life. Whilst I agree that it does not provide the same level of light control as a modern street lighting luminaire, I’m surprised that there is as much upward light and glare as indicated your photograph.

I will arrange for the column to be checked to make sure they are correctly aligned, and see if a baffle could be installed. However it is not always possible to install a baffle to the front of the lantern without adversely affecting the light performance on the road.

When the lighting approaches the end of its serviceable life, it will be assessed to see if lighting is still required in that area. If it is, a new lighting scheme will be designed and installed.  The new lighting will be modern efficient LED luminaires designed to minimise both upward light and intrusive light. These modern LED luminaires have a controlled light distribution and produce very little spill light when designed and installed correctly, and the addition of baffles can be more easily accommodated.

[Bildavis]

Black gorilla tape doubled over and reinforced with wire could create a simple visor baffle which could be taped to the side of the light fixture.  The curved shape would provide strength (monocot construction used in aircraft and originally in eggs)

The shape could be easily modified to block the direct and spill light as needed. The weight would be about 3 or 4 oz.

High wind might alter the shape or blow it off entirely but repair or replacement would be easy. And there would be a minimal risk of collateral damage. Cost would be <$10.

 

    I am facing the same sort of street light problem and cannot erect a shade because the electric wires to my house come off the same pole as the street light is mounted on. So I will be constructing one and suggesting the town attach it.

   Gorilla tape is a sort of super duct tape...

 

    

[Scooot]

It’s clearly an artificial light nuisance which would normally be covered by The Environment Protection Act 1990 but street lights are exempt. https://www.gov.uk/guidance/artificial-light-nuisances-how-councils-deal-with-complaints#how-artificial-light-nuisances-are-assessed

However the reason they are exempt is presumably to provide a benefit or safety to the general public. Nevertheless that shouldn’t mean they completely ignore the impact it has on the enjoyment of your property and they should endeavour to minimise the problem. Money shouldn’t really be a deciding factor, unless it was a ridiculous amount perhaps.

I would write to my MP setting out the problem, copy in the council. I’d also point out it infringes my human right for Protection of Property, article 1 of protocol 1 https://rightsinfo.org/the-rights-in-the-european-convention/

You understand that street lighting is necessary but the council are unreasonably ignoring the affect this light has on the enjoyment of your property and they could put more effort into finding a solution.

I’d guess that a letter from your MP to them would focus their minds a little more.

[laser_jock99]

If it helps - it took Warwickshire CC about a week and a half to fit two shades to new LED lights overlooking my back garden after my complaint via FIX MY STREET. The structural integrity argument is clearly b******s, but now they have said it they can't go back! Worth pointing out though every other council has no issues fitting these shades. You'll find the luminaire manufacturer has a range of pre-made shades for the lamps and the fitting holes are often pre-drilled in the newer LED lamps.

[nightfisher]

On 11/12/2015 at 11:54, Robp said:

So I have finally recieved a reply:

We have in the recent past had to replace a number of columns around the county which structurally failed earlier than expected. These units had been fitted with attachments which we consider on reflection were the cause of the early structural failure of the columns. Therefore for obvious reasons, we are now extremely cautious regarding allowing attachments that could affect the long term structural capability of a column.

With regard to signage, columns are designed to accommodate warning signs at a point 2m to 3m high on the column, but baffles are by their nature are positioned at the top of the column and can act like a sail and would amplify the wind loading. Also as they are rigid, additional twisting motions would also be added, thus putting the column under extra stress.

I feel this is going to take longer than expected to get resolved

You were lucky to even get replies, i had a battle with the local councils regarding an industrial premises that had failed to get planning permission for its bank of intersteller lighting, , the council eventually opened a case after constantly fobbing me of, this was 7 months ago when the case was opened, and i have heard nothing since, in the meantime the said factory has added even more lights