Unnecessarily Accurate Distances on Signs

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Bryn666
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Re: Unnecessarily Accurate Distances on Signs

Post by Bryn666 »

Stevie D wrote:
Chris Bertram wrote:What is the disadvantage in being precise? If you know it's 190 yds to the Give Way sign, why not say so?
Because round numbers (to one significant figure) are easier to process than those with extra digits. Most drivers can read and visualise 200yds quicker than 190yds, but in practical terms they are the same, drivers wouldn't be able to distinguish the difference between them.
Also I'm fairly sure the TSM is clear that rounding of distances is preferred for ease of comprehension when travelling at speed.

It's also why imperial bridge heights should always be in multiples of 3 inches.
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Re: Unnecessarily Accurate Distances on Signs

Post by A9NWIL »

Bryn666 wrote:
Stevie D wrote:
Chris Bertram wrote:What is the disadvantage in being precise? If you know it's 190 yds to the Give Way sign, why not say so?
Because round numbers (to one significant figure) are easier to process than those with extra digits. Most drivers can read and visualise 200yds quicker than 190yds, but in practical terms they are the same, drivers wouldn't be able to distinguish the difference between them.
Also I'm fairly sure the TSM is clear that rounding of distances is preferred for ease of comprehension when travelling at speed.

It's also why imperial bridge heights should always be in multiples of 3 inches.
Perhaps metric bridge heights should be rounded to the nearest 0.1metres then?
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Re: Unnecessarily Accurate Distances on Signs

Post by Berk »

lotrjw wrote:
Bryn666 wrote:
Stevie D wrote: Because round numbers (to one significant figure) are easier to process than those with extra digits. Most drivers can read and visualise 200yds quicker than 190yds, but in practical terms they are the same, drivers wouldn't be able to distinguish the difference between them.
Also I'm fairly sure the TSM is clear that rounding of distances is preferred for ease of comprehension when travelling at speed.

It's also why imperial bridge heights should always be in multiples of 3 inches.
Perhaps metric bridge heights should be rounded to the nearest 0.1metres then?
So if a bridge is actually 10' 2" high, it has to be signed as 10' dead, because it doesn't make 10' 3"?? And the same if it was 10' 4"??

This is perhaps my point about the metric mile being 1.5 k's to the mile. It would be far easier to convert - mentally, and on the ground (in terms of signage).
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Re: Unnecessarily Accurate Distances on Signs

Post by Bryn666 »

lotrjw wrote:
Bryn666 wrote:
Stevie D wrote: Because round numbers (to one significant figure) are easier to process than those with extra digits. Most drivers can read and visualise 200yds quicker than 190yds, but in practical terms they are the same, drivers wouldn't be able to distinguish the difference between them.
Also I'm fairly sure the TSM is clear that rounding of distances is preferred for ease of comprehension when travelling at speed.

It's also why imperial bridge heights should always be in multiples of 3 inches.
Perhaps metric bridge heights should be rounded to the nearest 0.1metres then?
They are.

A bridge that is 14 ft 11 inches would be signed at 4.5m / 14ft 9in.

The rounding rules are covered extensively in Traffic Signs Manual Chapter 4.
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Re: Unnecessarily Accurate Distances on Signs

Post by vlad »

Bryn666 wrote:
lotrjw wrote:Perhaps metric bridge heights should be rounded to the nearest 0.1metres then?
They are.
You mean: They should be. Not all are....
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Re: Unnecessarily Accurate Distances on Signs

Post by Bryn666 »

Unlawful traffic sign and should be removed forthwith and replaced with the correct one. :twisted: :twisted: :twisted:
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Re: Unnecessarily Accurate Distances on Signs

Post by Jonathan B4027 »

Cornets End with a random 54 yards
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Re: Unnecessarily Accurate Distances on Signs

Post by Big L »

Thread-bump ahoy!

I passed this 186 yds sign and thought of this thread.
Make poetry history.

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Re: Unnecessarily Accurate Distances on Signs

Post by trickstat »

Big L wrote: Sun Jul 07, 2019 17:33 Thread-bump ahoy!

I passed this 186 yds sign and thought of this thread.
By my reckoning that's very close to 170m.
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Re: Unnecessarily Accurate Distances on Signs

Post by TS »

It's been going on for a long time. My father took this photo in about 1964.

1767 yards – that's 7 yards beyond a mile!
1767.jpg
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Re: Unnecessarily Accurate Distances on Signs

Post by Viator »

Image

One mile, one and a quarter furlongs ...or 2,035 yards, if you prefer.
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Re: Unnecessarily Accurate Distances on Signs

Post by Was92now625 »

trickstat wrote: Sun Jul 07, 2019 23:49
Big L wrote: Sun Jul 07, 2019 17:33 Thread-bump ahoy!

I passed this 186 yds sign and thought of this thread.
or ten yards past a tenth of a mile

By my reckoning that's very close to 170m.
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Re: Unnecessarily Accurate Distances on Signs

Post by Was92now625 »

Was92now625 wrote: Wed Jul 10, 2019 16:53
trickstat wrote: Sun Jul 07, 2019 23:49
Big L wrote: Sun Jul 07, 2019 17:33 Thread-bump ahoy!

I passed this 186 yds sign and thought of this thread.

By my reckoning that's very close to 170m.
or ten yards past a tenth of a mile
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Re: Unnecessarily Accurate Distances on Signs

Post by the cheesecake man »

Humps for 1317 yards . Not three quarters of a mile. No, much less than that.
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Re: Unnecessarily Accurate Distances on Signs

Post by Big L »

In the middle of nowhere and important enough for two warning signs, apparently.
Make poetry history.

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Re: Unnecessarily Accurate Distances on Signs

Post by TS »

This is a good one, in West Downs, just south of Delabole in Cornwall:
20190803_172033.JPG
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Re: Unnecessarily Accurate Distances on Signs

Post by jervi »

Unfortunately I don't have any photos of them, or could find any on Gmaps. But when I was driving up the M23, in the roadworks they have got height restriction signs under every guantry and bridge, rounded to the nearest 0.1cm
So you get signs like 5.188m
I think it is a bit unnecessary tbh
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Re: Unnecessarily Accurate Distances on Signs

Post by Vierwielen »

Bryn666 wrote: Sat Mar 04, 2017 17:49
lotrjw wrote:
Bryn666 wrote:
Also I'm fairly sure the TSM is clear that rounding of distances is preferred for ease of comprehension when travelling at speed.

It's also why imperial bridge heights should always be in multiples of 3 inches.
Perhaps metric bridge heights should be rounded to the nearest 0.1metres then?
They are.

A bridge that is 14 ft 11 inches would be signed at 4.5m / 14ft 9in.

The rounding rules are covered extensively in Traffic Signs Manual Chapter 4.
Actually 4ft 11in would be rounded down to 14ft 6in. not 14ft 9in.
The metric equivalent of 4.5466 m would be rounded down to 4.4 m.
In both cases an initial safety factor of 3 inches or 7 cm is built into the rounding.
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Re: Unnecessarily Accurate Distances on Signs

Post by the cheesecake man »

Cropredy 1/2
Claydon 1 1/4
Aston le Walls 3
Appletree? 2? 1 3/4? No neither of those are good enough : it's got to be 1.9.
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Re: Unnecessarily Accurate Distances on Signs

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