Siting Chambers

Okay, let's keep it simple to start off with.

There are chambers marked all over your Google Earth map. Go and look at one of the first ones you are going to be putting in the ground.

Is it in a position where you could get a 4 X 4 vehicle towing a horsebox to within 3 or 4 metres?

If it isn't, is there anywhere better you could site it, to within say 40 metres of this point? - with all the digging routes still making sense. (preferably somewhere along the core line rather than to the side)

If it is, could it be improved slightly to make it even easier to get to.

Have you thought about access during bad weather, farming activity, etc. And what about traffic, is it too busy to park there, would you be in the way if you parked there? Is it too obtrusive there? Could it be moved a bit to make it less obvious and nicer looking, but still be within splicing range? It can be worked from just over a wall for example rather than at track side.

If this has given you a good location then just go ahead and relocate it. Mark it on a map and send the map to Edward at B4RN

If you are doing a major reroute of the duct lines, then you will probably be abandoning this location anyway. Go back to those criteria to see if you can find a suitable place, that is no more than 800m from its adjacent chambers.

That would leave you with some cases where you cannot find a suitable place and meet all those criteria.

The purpose of a chamber is

To minimise digging distances
To be able to access the core fibre at convenient distances for blowing
To contain spare fibre
To connect spurs to the Core Route

A blowing chamber is a chamber without any spurs, it would usually not contain a bullet, but if there was difficulty blowing fibre then it could have to be joined. A blowing chamber only really needs access on blowing day – it is likely to be accessed once in its lifetime. It would usually need one visit by vehicle, to get a compressor near it. B4RN have some long hoses and could do it from 30 metres. If really necessary B4RN can dig down to the fibre at any point and blow from there and blow straight through the chamber. So the chamber would not necessarily need vehicle access.

Chambers with spurs may be needed to be accessed several times.

· For blowing, as above
· For a Core splice if necessary, which could take half a day. nice day.
· To splice in any spurs as they become ready for service. To add in a spur should take less than half an hour.

Splicing can be done inside a tent, or outside on a nice day. It would require a bit of lugging of equipment and wouldn't be nice in wind or rain, but it can be done.

So in terms of access the chamber can be anywhere and B4RN can manage. But some locations mean the job is a lot easier.

How far apart do chambers need to be? The general rule of thumb is something like 500 to 800 metres. It should be at the lower end of the range if it is a large fibre size, as this is harder to blow. It should be at the lower end if the ground is known to be rocky or undulating. It can be at the upper end if there are plenty of access points along the route. It can be at the upper end if it is all a nice steady slope. If the chambers are TOO close then this is just a waste of time and cost of putting the chamber in. if the chambers are TOO far apart then it may involve extra digging and fleeting.

So we would ideally like

Chambers to be between 500 and 800 metres apart
Situated somewhere with close access
Sensibly located to minimise total digging

In the case where you cannot meet these criteria, then

You could see if moving an adjacent chamber can improve things at this chamber
If the fibre count is below 144 you could increase the inter-chamber distance up to 850 metres, but maybe no further
If there is no fibre change at the chamber you could have it further away from immediate access
You could consider putting 2 chambers in rather than 1

Notes

Moving a chamber may mean it has to be upgraded to a large chamber if it might be driven over

The landowner will get a chance to say if he is happy with the location, and could make the final decision.

Red pin is the original. Yellow pin is laid. Here someone has correctly identified the house, but they actually want the connection to the office. Which is in a new building that doesn't yet appear on the satellite map.

The chamber can be relocated nearer the office, having checked that it is easy to drive round to there

Red pin is the original. Yellow pin is laid.

The original has no track anywhere near. The obvious alternatives are the left and the right tracks. As it happens it can be moved to the right one, and that can serve the cluster of houses at the very right.

Red pin is the original. Yellow pin is laid.

This one is purely the farmer's preference. His land gives him some authority to say where it goes. They might have to drive over the grass a bit, but once you warn the farmer of that fact, then you have permission.

Red pin is the original. Yellow pin is laid.

Another mistaken house. The living quarters are in the left half of those buildings, so the simplest position for the chamber is where the house spur can conveniently come in via fields.

Red route is the original plan. Chamber is in a decent place. It seems as though it's a bit to the right (it supplies all those buildings), but it's out of sight and next to a quiet road.

Orange route. Then there is a problem with a landowner somewhere a mile away which means we need a new link to the north. B4RN get permission to cross the river there and send us the revised Orange route giving us an awkward stream crossing on its way to the original chamber position

Green route. We immediately think how about moving the chamber to the Green position. That avoids the stream, it's out of the way of the houses, next to the road still, and more central for all the houses.

Yellow route. On closer inspection we find there is a place among the houses where we can locate the chamber out of everyone's way and giving a shorter route to the north.

Bear in mind that the guy sitting in the office, drawing plans for you, may not own as many muddy gloves as you, he will have different experiences. So when you get sent the red route and immediately scratch your head and sigh, he is remembering an asparagus field in Melling where you had to tip-toe round the edge of the field, going through all the rubble that will next to the buildings, and having to turn your moleplough through right angles.

You know your land better, your job is to contribute. And whatever you do, do not turn up at the farmhouse with a print-out of that red route - the farmer will lose confidence in you immediately.

Chamber positioning

There are plenty of reasons why a chamber ends up in a daft place - for example the landowner might insist it goes in that particular spot, but looked at on a map some look a bit strangely positioned. Three examples from Garsdale, one from Dentdale and one from Casterton.

Couldn't that have easily have been placed closer to the road? It's 40 metres away.

Completely nowhere. The fibre blowers happened to be able to drive over the fields in summer, just after haymaking, otherwise it is often inaccessible.

Wasn't there anywhere there with better access nearer the buildings?

That house is the only spur from that chamber. There is a nice track near where the spur branches off. Why isn't the chamber there?

Why wasn't that down by the road?

Small or Large Chamber?

It has to be a large chamber if

There are greater than 8 connections to be made off it, or
There are more than 72 splices to be made in the bullet , or
If highway or cattle traffic is expected to cross it.

So if it needs a big bullet or it needs a strong roof

This is the view down from a level track to a chamber. On the map it is the view from the yellow pin to the red pin. The red pin is where the chamber was located on our first B4RN map. On the map it looks a reasonable location.

Q to Contractor (after having visited it for the first time, to blow fibre, in a gale): Why did you put it right down there? Did you have trouble getting up to the verge of that track?

A from Contractor: No I could have put it up there, I was told to put it down there by XXX

There appears to be a new square chamber.

The one on the left is a 450X450 chamber with a concrete lid - a blowing chamber for verges, etc - but only used occasionally and only by Nick's gang at present.

And there seems to be a plastic version.

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