Changeable Message Signs

Welcome to Changeable Message Signs

Changeable Message Signs, sometimes called Uniform Manual Traffic Control Devices, are an effective tool to provide real-time traffic regulatory, warning, or guidance information to the traveling public. In most cases, the messages displayed on CMS are related to traffic delays, travel times, lane closures, rerouting due to traffic incidents, and similar strategies to manage traffic actively on the highway system.  With few exceptions, the SOP limits the use of CMS to the display of traffic operational, regulatory, warning, and guidance information. 

Our Changeable Message Signs system is operated through SAR's Computer Aided Dispatch (CAD) system. The link to this CAD can be found here. To access the CMS system, you must have access to the Department of Motor Vehicles page on the CAD - People with access to this page are hand picked by the Public Works Leadership Team and given and unique key to enter into SAR's CAD, to gain access to the DMV page and subsequently the 'Street Signs' page. 

Included in this SOP

The following SOP will use a variety of methods to simplify the required structure of CMS messages, including visual representations of the messages on a matrix board - Below you can see an example of such a diagram. Additionally, through out this SOP the rows on the CMS boards will be referred to as 'ROW A', 'ROW B' and 'ROW C', all of which can also be seen below in their respective positions.

Computer Aided Dispatch (CAD)

If you are reading this then chances are you have access to both the SAR CAD and the DMV section of the CAD. As previously stated, the unique key for the DMV section of the CAD is given to hand-picked server members and given to all members of the Law Enforcement faction. 

Once you have entered the correct key, you will now be able to see a tab labeled 'DMV' on your CAD home screen. Clicking on this tab will take you to a secondary page, which will include another tab labeled 'Street Signs'. Entering this page will guide you to the main area where all CMS displays, across San Andreas, can be monitored & controlled.

Given to you is the exact road name and postal of each individual CMS board, including the direction of the flow of traffic on that specific road. You are also given a Search Bar, which you can use to search for a specific road name or postal to save time. Each CMS display is divided into rows A, B & C and this is also represented in each display controller on this page. Although the controllers do not show that the text is centered, rest assured it will be centered in the game. Each row on the controllers has a 14-character limit. 

Below you can see an example of a properly formatted CMS display on one of the controllers.

Guidelines for Message Contents and Formatting

Our job is to ensure that our CMS displays are informing and as easy to read as possible. It is therefore essential, that all PW employees follow the following guidelines when operating our CMS system.

• Limit each row of the CMS to just one unit of information if possible. Do not add more than two units of information per row if possible.

• No more than three units of information should be included in the entire message, at any time.

• If the board is displaying one unit of information, it may be spread across all 3 rows. However, Row B should contain the most words.

• Words & Place Names should not be split between the rows, if possible.

• The word 'EXIT' shall be used when referring to any road which directs traffic to exit a freeway.

• The word 'RAMP' shall be used when referring to any road which directs traffic to enter a freeway.

The following is strictly prohibited from being displayed on CMS Boards:

• Date and time (except as related to expected roadway or traffic conditions, such as planned closures or other events affecting traffic)

• Display of Web site or e-mail addresses, uniform resource locators (URL), domain names, metadata tags ("hashtags"), electronic device applications ("apps"), or similar forms

• Display of telephone numbers (except as specifically allowed)

• Display of statistics, such as highway fatalities or summonses issued

• Personal safety messages (e.g., WEAR SUN SCREEN)

• Promotional advertising (commercial or non-commercial)

• Public awareness campaigns unrelated to traffic operation or safety

• Public safety alerts (except homeland security and AMBER alerts as described herein)

• Public service announcements

• Sponsor acknowledgment

• Weather conditions or advisories (except as related to expected adverse road-weather conditions)

• Any use of video, motion, flashing, or other graphic features.

Formatting Examples

Below you can see an example of a correctly formatted CMS display. Each row contains a separate set of information and only 3 units of information are displayed on the entire board. In this example, Row A is advising drivers of the reason for the warning, Row B states the location of the warning and Row C commands the driver to take a specific action to avoid the warning - In this case it's COLLISION, AHEAD, SLOW DOWN.

Seen below is the same message but formatted incorrectly. As you can see, two sets of information have been merged together and split between two rows. In row B the CMS is displaying the location of the hazard 'AHEAD' and the beginning of the command to the driver 'SLOW'. The command is split apart between Rows B & C, leading to confusion and longer reading times. Two units of information can be displayed in the same row, but it should be avoided whenever possible.

One unit of information can be displayed across the entire CMS board if so desired. However, as stated above, Row B should be prioritized and contain the most words if possible. An example can be seen below, 'SLOW' is the only unit of information on this display and it is correctly placed in Row B. Placing this word in Rows A or C would be incorrect and highly discouraged.

AMBER Alerts

AMBER stands for America's Missing: Broadcast Emergency Response and it is a U.S. Department of Justice program used to respond to the abduction of a child. AMBER alerts must be declared by an on-duty LEO Supervisor or LEO Command Member, before messages can be displayed on our CMS boards. AMBER Alert messages are typically a three-line message that provides information to motorists on the abduction of a child. The message should display a vehicle description and license plate number (or partial number). 

The following guidelines must be strictly followed when creating an AMBER Alert display, as to allow for the best readability and uniformity across the state.

• AMBER Alerts can be displayed on any and all signs across the state, which are otherwise not in use.

• Row A should ONLY include the text 'CHLD ABDUCTION'.

• Row B should include a vehicle description, including the color, make & model if possible. They should also follow that exact order in the row.

• Row C should include the state of the vehicles registration & the license plate. (For example: SA 12ABC345) 

Below you can see a correctly formatted AMBER Alert, as seen on a CMS Display.

Blue Alerts

Blue Alert messages consist of a three-line message that provides information on a suspect’s vehicle to motorists following an attack on a law enforcement officer. The message should display a vehicle description and license plate number. Blue alerts must be declared by an on-duty LEO Supervisor or LEO Command Member, before messages can be displayed on our CMS boards - Most commonly, a Blue Alert will be posted in #leo-advisories.

The following guidelines must be strictly followed when creating an Blue Alert display, as to allow for the best readability and uniformity across the state.

• Blue Alerts can be displayed on any and all signs across the state, which are otherwise not in use.

• Row A should ONLY include the text 'CALL 911'.

• Row B should include a vehicle description, including the color, make & model if possible. They should also follow that exact order in the row.

• Row C should include the state of the vehicles registration & the license plate. (For example: SA 12ABC345) 

Below you can see a correctly formatted Blue Alert, as seen on a CMS Display.

Place Holder Messages

Often times, you will notice that CMS Boards will generally be empty or unused across the map, especially if the current AOP does not include a major highway network. However, if the AOP does include a highway you may want to display some miscellaneous messages on the CMS Boards, to keep road users informed. Below you will find a series of random, non-specific messages that can be displayed anywhere across the state. Feel free to use these messages as place-holders on unused CMS Boards.

Authorized Abbreviations

Listed below are all of the authorized abbreviations that can be used on all CMS boards, in case of limited space. If a abbreviation is not listed here then it shall not be used, unless authorized by a member of the leadership-team. Where shown, prompt words should be used for clarification.

Working with Law Enforcement