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(There is no requirement to post signs at right turns saying, "stop before turning" or something like that.
  See the bottom of this page for more details.)

Warning Sign Requirements

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New 12-9-02, updated 9-29-12:

Until Jan. 1, 2013, the Vehicle Code (excerpted below) required the posting of warning signs like the one depicted below, "visible to traffic approaching from all directions" at each camera-equipped intersection, or at all the main entrances to town.  Most cities posted enough signs but not all signs complied with the CalTrans specifications - particularly as to the minimum size of 30 x 42 inches.

CVC 21455.5. (a) The limit line, the intersection, or a place designated in Section 21455, where a driver is required to stop, may be equipped with an automated enforcement system if the governmental agency utilizing the system meets all of the following requirements: (1) Identifies the system by signs that clearly indicate the system's presence and are visible to traffic approaching from all directions, or posts signs at all major entrances to the city, including, at a minimum, freeways, bridges, and state highway routes.  (Former version of CVC 21455.5(a).)

After Jan. 1, 2013, a new law (see SB 1303 on the Legis page) requires that there be a sign near each camera - and there no longer is the option to post
the entrances to town.

Here are some of the other laws about road signs.

CVC 21400. The Department of Transportation shall, after consultation with local agencies and public hearings, adopt rules and regulations prescribing uniform standards and specifications for all official traffic control devices placed pursuant to this code, including, but not limited to, stop signs, yield right-of-way signs, speed restriction signs...

CVC 21401. (a) Except as provided in Section 21374, only those official traffic control devices that conform to the uniform standards and specifications promulgated by the Department of Transportation shall be placed upon a street or highway...

CVC 21465. No person shall place, maintain, or display upon, or in view of, any highway any unofficial sign, signal, device, or marking, or any sign, signal, device, or marking which purports to be or is an imitation of, or resembles, an official traffic control device or which attempts to direct the movement of traffic or which hides from view any official traffic control device.

CVC 21467. Every prohibited sign, signal, device, or light is a public nuisance, and the Department of Transportation, members of the California Highway Patrol, and local authorities are hereby authorized and empowered without notice to remove the same, or cause the same to be removed, or the Director of Transportation, the commissioner, or local authorities may bring an action as provided by law to abate such nuisance.

You can also download two clearer versions of this chart, as follows.
If you would like to see a somewhat clearer scan of this document, click here:
Warning Sign Reqs., with Signature (jpeg - 80 kb)
If you would like to see a very clear pdf copy of this document, but without signature, click here:
Warning Sign Reqs., without Signature (pdf - 15 kb)

This document is not yet available on the CalTrans website.

More About This Issue Before The Courts

If "your" city has undersized signs and you are going to raise that issue in court, you will need to be prepared to deal with the following sort of reasoning by the judge:  During a Sept. 2003 trial of a ticket issued before Culver City's March 2003 posting of full-sized signs, Comm. Amado ruled that (overall) size doesn't matter - since the picture of the signal and the lettering on the then-undersized signs were the same size as those required for the full-sized signs, the fact that the overall dimensions were too small would not matter.  Judges in other towns may see it the same way - or differently, of course.

Culver City:  During the Aug. 5, 2004 trial of a ticket issued at Sepulveda / Machado in Culver City the defendant pointed out that there was no warning sign on the large driveway (for a housing complex) that makes up the 4th side of that intersection.  Comm. Amado ruled that it is not required to post signs facing traffic coming from private property.

CalTrans Letter

Here is an August 2003 CalTrans letter giving their official position about sign requirements.
If you want to use this letter in court, you'll need to call CalTrans and get them to mail you a paper copy with a signature in ink.  Such a letter isn't hearsay when it's from a government official.  It comes under an exception called official writings.  The exception is necessary so that high government officials don't have to spend all their time testifying about government policy in courts all over the place.

GRAY DAVIS, Governor

1120 N STREET, MS 36
P. O. BOX 942873
SACRAMENTO, CA 94273-0001
PHONE (916) 654-2352
FAX (916) 653-6080
TTY (916) 653-4086

Flex your power! Be energy efficient!

August 6, 2003

Dear Mr. ---------:

I am responding to your telephone call about the PHOTO ENFORCED (SR56) sign. I hope the following information will be helpful.

The California Department of Transportation (Department) is responsible for developing standards and specifications for traffic signs. For the last 5 years I have been in charge of the Signs and Work Zones Branch, which designs official traffic signs for use on all public roadways in the State of California.

California Vehicle Code (CVC) Section 21400 provides that the Department shall, after consultation with local agencies and public hearings, adopt rules and regulations prescribing uniform standards and specifications for all official traffic control devices placed pursuant to the provisions of the CVC. CVC Section 21401 provides that only those official traffic control devices that conform to the uniform standards and specifications promulgated by the Department shall be placed upon a street or highway.

In keeping with the requirements of CVC Section 21400 the Department established the California Traffic Control Devices Committee to consult with local agencies. The Committee is comprised of representatives of State and local governments. The Committee holds public hearings at least 3 times during each calendar year. For more information, visit the California Traffic Control Device Committee’s homepage at:

The PHOTO ENFORCED (SR56) sign was adopted by the Department on September 5, 1996, after consultation with the California Traffic Control Devices Committee and public hearings. The adopted specification for the SR56 is enclosed. It is the official standard of the Department. It has not changed since it was originally signed. The SR56 specification and other sign specifications are available for purchase at:

Department of Transportation
Publication Distribution Unit
1900 Royal Oaks Drive
Sacramento, California 95815-3800
(916) 445-3520

The style, font, size and spacing of letters and numerals on traffic signs conform to the requirements specified in the Federal Highway Administration (FHWA) publication entitled "Standard Alphabets for Highway Signs and Pavement Markings," which is available for purchase from the FHWA web site at:

The Department and local agencies have some flexibility in the size of signs. However, signs must be conspicuous and legible to drivers. In Section 4-01.12 of the Department’s 1996 Traffic Manual it states, “Larger sizes may be used where greater legibility or emphasis is needed. Special signs or large signs are prescribed for freeways and expressways. Under special conditions such as alleys, limited parkway widths, parking facilities, parks, etc., the use of approved sizes smaller than standard size signs may be justified based on engineering judgement. When sign sizes are changed, standard shapes and colors shall be used and standard proportions shall be retained insofar as practicable.” The 1996 Traffic Manual is available for viewing on the Department’s web site at:

Cities and counties, not the Department, are responsible for installing signs on local streets and roads. CVC Section 21100 (d) allows local authorities to adopt rules and regulations for regulating traffic by means of official traffic control devices meeting the requirements of CVC Section 21400. CVC Section 21351 allows local authorities to place and maintain such official traffic control devices.

Thank you for writing. I hope this helps.


Greg Edwards, Chief

Highway Signs and Work Zones Branch

(916) 654-3507



Signs for Right Turns?

There is no requirement to post signs at right turns saying, "Stop Before Turning" or something like that.
  If there was such a requirement, there would have to be four such signs at every signalized intersection in California.  So, the requirement is simply something you are supposed to know, and is part of the written driving test.
If a city decided to make up their own signs saying "Stop Before Turning" or "After Stop, Right Turn Permitted on Red," they would be in violation of CVC 21401 and 21465 (above).

If you could swear that you have seen such a sign, you may have been to South San Francisco, or Millbrae.

Illegal sign in South San Francisco
Sign in South San Francisco, from 2010  Grand Jury Report

  At an intersection where rolling right turns are a major safety problem and camera enforcement has failed to reduce the violations, and at those few locations where it's necessary to prevent all right turns during the red, the city should install a Blank Out sign.  Blank Out signs are large (24" x 24" or bigger) electrically-powered signs whose messages are not visible when the power is off.  Thus, they provide the ability to prohibit right turns during selected portions of the signal cycle.
This Blank Out sign has the added advantage that its message is not in English - see Why Not in Greek, below.

Tapco blank out sign - no right turn
Blank Out Sign

Federal Guidelines for Signs

From Chapter V. of the Federal Highway Administration's Red Light Camera Systems Operational Guidelines (with emphasis added):

( Please note that these are guidelines and compliance is not mandatory;  in the Introduction to the Guidelines, it says, "Although not a regulatory requirement, the guideline is intended to provide critical information for State and local agencies on relevant aspects of red light camera systems in order to promote consistency, proper implementation, and operation..." )

Federal Guidelines, Chapter V., Warning Signs section (pg. 21, or 27th pg. of the pdf)

Signs warning motorists that red light cameras are being used are typically required by law or ordinance, but whether required or not, should be posted as part of the driver awareness and education process.  These warning signs may be placed in the following locations at photo-enforced intersections:
·        In advance of photo-enforced intersections.
·        At photo-enforced intersections, typically on the far side traffic signal pole.
·        On all approaches into an area where red light camera systems are used for red light running.

Warning signs placed on all approaches into an area, while used to satisfy legal requirements in some jurisdictions, are appropriate as supplemental warning signs but not as the primary warning for motorists.  Advance warning signs should be installed at photo-enforced intersections.

All advance warning signs should be clearly visible and compliant with the MUTCD (17).

California has adopted its own version of the Federal guidance applicable to sign placement. My detailed discussion is at: 

Sign Placement - New (MUTCD) Guidance.

Why Not In Greek?

We have a lot of tourists in California, and due to the State's size and general lack of a public transportation system many of them rent cars and drive.

For those not fluent in English, the CalTrans-approved "Photo Enforced" warning signs might look like this:

Photo enforced, in Greek

...and South San Francisco's "After Stop, Right Turn Permitted on Red" sign must look like this:

In Spanish: After stop right turn
                    permitted on red 

The two signs above were made up by  We are sure that in Greece and Mexico, the warning signs use international symbols that can be understood by all nationalities.

Here is a sign not made up by

Actual Blank Out Sign on Canoga Avenue in LA

This Blank Out sign has been set up to flash, in an effort to prevent motorists from making right turns on red across Metro's Orange Line busway in Los Angeles.  But it hasn't been effective, probably because it depends upon the motorist's understanding of an English word and also fails to tell the driver what to do, or not to do (don't turn right).
Further, it is an unapproved sign (not listed in CalTrans' MUTCD), so exposes Metro and the City of LA to liability in the event of an accident.

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