[PRCo] Re: 42/38 on Smithfield Yellow-Green Light

[Herb Brannon]

Wikipedia also wraps up the section on "flashing green light" with the
following sentence:
*The new US 2009 Manual of Uniform Traffic Control Devices specifically
prohibits flashing any green signal indication

*I forgot to include that in my last post.

On Thu, Oct 27, 2011 at 18:50, Herb Brannon <hrbran at cavtel.net> wrote:

> Page 251 of the 2009 manual states, "A flashing green signal has no meaning
> and shall not be used."
>
> Boston has either obtained an exception or is not in compliance with the
> uniform traffic standards.
>
> I checked the Massachusetts official drivers manual and no mention is made
> of a "flashing green".
>
> However, Wikipedia gives the following information:
> *
> FLASHING GREEN LIGHT*
>
> In British Columbia <http://en.wikipedia.org/wiki/British_Columbia>[14]<http://en.wikipedia.org/wiki/List_of_variations_in_traffic_light_signalling_and_operation#cite_note-13>and a few U.S. states, a flashing green globe signal is used at a pedestrian
> crossing <http://en.wikipedia.org/wiki/Pedestrian_crossing> or
> intersection, at which pedestrians have the ability to stop traffic to allow
> a safe crossing. They may also be used at a drawbridge. The flashing green
> indicates that the signal is not currently in use. As soon as a pedestrian
> pushes the button to trigger the signal, the light changes to solid green
> for a short time before entering the normal yellow/red/green sequence, then
> returns to flashing green until another crossing is requested; however, in
> some places such as Vancouver <http://en.wikipedia.org/wiki/Vancouver>, it
> goes directly from flashing green to yellow, leaving out the solid green
> sequence. *In Massachusetts, specifically in Cambridge and Somerville, the
> main street will have a flashing green signal, while cross streets have a
> signal that have a red on top, yellow in the middle and flashing red in the
> bottom position. When a pedestrian activates the signal, the cross street
> changes from flashing red in the lowest position to yellow to red (topmost
> position).*
> Wikipedia seems to have the answer.
>
>
> On Thu, Oct 27, 2011 at 16:20, Barry, Matthew R <mrb190 at pitt.edu> wrote:
>
>> Interesting about Boston.   Yes, what the heck does flashing green mean?
>>
>> Found this about the Pittsburgh yellow-green combo:
>> http://en.wikipedia.org/wiki/Pittsburgh_left
>>
>>
>>
>> -----Original Message-----
>> From: pittsburgh-railways-bounce at lists.dementix.org [mailto:
>> pittsburgh-railways-bounce at lists.dementix.org] On Behalf Of BobDietrich
>> Sent: Thursday, October 27, 2011 4:17 PM
>> To: pittsburgh-railways at dementix.org
>> Subject: [PRCo] Re: 42/38 on Smithfield Yellow-Green Light
>>
>> So if it is consistency we have why is Boston still flashing GREEN?  I saw
>> that last week and almost wrecked, I didn't know what to do!!!!
>>
>> -----Original Message-----
>> From: pittsburgh-railways-bounce at lists.dementix.org
>> [mailto:pittsburgh-railways-bounce at lists.dementix.org] On Behalf Of Fred
>> Schneider
>> Sent: Thursday, October 27, 2011 2:31 PM
>> To: pittsburgh-railways at dementix.org
>> Subject: [PRCo] Re: 42/38 on Smithfield Yellow-Green Light
>>
>> It ended when the feds wanted consistency everywhere.   They never managed
>> to get it everywhere ... Florida and Texas mount traffic lights
>> horizontally to confuse the color blind.
>>
>> At the same time New York City scrapped their lights that simply went from
>> green to red.   Marietta, Ohio used to have green and red lights that
>> flashed red over green three times as a warning before the green went out.
>> They also disappeared about the same time.   There were a lot of odd
>> variants at one time.  Some cities had lights where the green was
>> sequential .... started at the bottom and progressed up a ladder until it
>> turned red.
>> Seems to me Reading, PA had a version like that back in the 1930s or 1940s
>> but it was not still around in the 1970s.
>>
>>
>>
>> On Oct 27, 2011, at 2:20 PM, Barry, Matthew R wrote:
>>
>> > No, Bob.  That practice ended in Pittsburgh - I  think in the late 70s.
>> >
>> > -----Original Message-----
>> > From: pittsburgh-railways-bounce at lists.dementix.org
>> [mailto:pittsburgh-railways-bounce at lists.dementix.org] On Behalf Of Bob
>> Rathke
>> > Sent: Thursday, October 27, 2011 2:18 PM
>> > To: pittsburgh-railways at dementix.org
>> > Subject: [PRCo] Re: 42/38 on Smithfield Yellow-Green Light
>> >
>> >
>> > Don't the traffic lights in Pittsburgh still have the overlapping
>> green/yellow indication?
>> >
>> >
>> >
>> > I recall that in the 1960's Pittsburgh was one of the few (maybe the
>> > only)
>> city in the U.S. with overlapping traffic signals.  Also in that era,
>> Canton, Ohio had simple red & green traffic signals - no yellow.
>> >
>> >
>> >
>> > Bob
>> >
>> >
>> >
>> > ----- Original Message -----
>> >
>> >
>> > From: "Matthew R Barry" <mrb190 at pitt.edu>
>> > To: pittsburgh-railways at dementix.org
>> > Sent: Thursday, October 27, 2011 12:21:58 PM
>> > Subject: [PRCo] 42/38 on Smithfield  Yellow-Green Light
>> >
>> > Hi Folks,
>> > Take a look at this of the 42/38 on Smithfield:
>> http://www.railpictures.net/viewphoto.php?id=275722&nseq=45
>> >
>> > Remember when the traffic lights used to give us "green" THEN   "green
>> and
>> yellow together," then "yellow," and finally "red?"    The photo
>> illustrates
>> the former green/yellow signal.
>> >
>> > Matt
>> >
>> >
>> >
>> >
>> >
>> >
>>
>>
>>
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>
>
> --
> Herb Brannon
> In Cuyahoga Valley National Park
>



-- 
Herb Brannon
In Cuyahoga Valley National Park