Whistle post

Whistle post

A whistle post (or whistle board), in railroad usage, is a sign marking a location where a locomotive engineer is required to sound the horn or whistle.

United States

Whistle posts in the United States were traditionally placed about one-quarter mile in advance of a road crossing.The signs in themselves varied in design from railroad to railroad. Some were marked with – – o – (two longs, one short, and another long) in a similar manner of sending the letter Q in Morse Code. This sequence is known as "Rule 14(l}" " Rule # 14(l) - Approaching public crossings at grade, to be prolonged or repeated until crossing is reached unless otherwise provided'. [Cite book|title=Rules for conducting transportation, The official employee operators manual|publisher=Penn Central Railroad|date=28 April, 1968|] This rule is applied in almost all U.S. railroad operating rule books. Generally, even if the advance warning provided by the horn will be less than 15 seconds in duration. This signal is to be prolonged or repeated until the engine or train occupies the crossing; or, where multiple crossing are involved, until the last crossing is occupied.The same rule is practiced when approaching locations such as rail yards, where men may be working on the tracks as well as bridges, tunnels and other points.

Modern whistle posts are of simple sheet metal construction, utilizing a 'W' marker. Some multiple crossings protected by a single sign have an 'X' displayed below the 'W', other multiple crossings may have 2 or 3 W markers on the same post..Whistle posts used on the former Southern Pacific display an 'X'. Multiple crossings have a number displayed beneath the 'X' for the number of crossings.

United Kingdom

Modern whistle boards in the UK comprise a white circular sign bearing a letter 'W'. Early whistle boards generally had the word "Whistle" written in full on a rectangular board. The Great Western Railway's signs had 'SW' for "Sound Whistle".

One modern variation found in Scotland is the 'continuous' whistle board, comprising a white rectangle with the 'W' below a diagonal cross. The driver must sound the horn continuously on the approach to the level crossing ahead.

Republic of Ireland

In Ireland, a whistle post is an upright rectangle bearing black and yellow diagonal stripes.


In France, a whistle board comprises a black rectangular board bearing a white letter 'S' for "Sifflez" (= "whistle"). An additional white board with a black 'J' for "Jour" (= "day") indicates that the sign does not apply at night time.


In Germany, a rectangular board bearing the letter 'P' for "Pfeifen" (= "whistle") is used as a whistle board. It may have either a black 'P' on a white background, or a white 'P' on a black background. Two boards, one above the other, means "whistle twice".

Where an additional sign with two vertical stripes is mounted above the 'P' sign, that sign only applies to trains that are not stopping ahead (e.g. at a station).


In Poland, a whistle board comprises a white triangle with a black border. A whistle board associated with a level crossing depicts the silhouette of a car in the middle of the triangle.

People's Republic of China

In the People's Republic of China, a whistle board is a white diamond with a black border with the character míng 鸣 (whistle) on it.


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • whistle post — noun : a marker alongside a railroad track designating a point at which trains are to whistle (as for a station or crossing) …   Useful english dictionary

  • whistle — Synonyms and related words: Angelus, Angelus bell, English horn, Klaxon, Mayday, Pandean pipe, SOS, air raid alarm, alarm, alarm bell, alarm clock, alarm signal, alarum, alert, all clear, anthem, assibilation, aulos, bagpipe, ballad, basset horn …   Moby Thesaurus

  • Whistle blowing — Hinweisgeber oder Whistleblower (abgeleitet von der englischen Redewendung „to blow the whistle on someone“, zu deutsch „jemanden verpfeifen“) bezeichnet einen Informanten, der Missstände, illegales Handeln (z. B. Korruption, Insiderhandel) oder… …   Deutsch Wikipedia

  • Train whistle — A train whistle or air whistle, (originally referred to as a steam trumpet), is an audible signaling device on a steam locomotive used to warn that the train is approaching, and to communicate with rail workers.The older steam whistles were… …   Wikipedia

  • Tin whistle — Infobox Instrument color1=#FFD700 color2=#FFEC8B name=Tin whistle names=Pennywhistle classification= *Woodwind *Wind *Aerophone range=Two octaves related= *Simple system flute *Pipe and taborThe tin whistle, also called the tinwhistle, whistle,… …   Wikipedia

  • Tin whistle — Différents tin whistles en ré de gauche à droite : Clarke Sweetone ; Shaw (modifié) ; O Brien ; Reyburn ; Generation (modifié) ; Copeland ; Overton …   Wikipédia en Français

  • Dog-whistle politics — Dog whistle politics, also known as the use of code words, is a term for a type of political campaigning or speechmaking which employs coded language that appears to mean one thing to the general population but has a different or more specific… …   Wikipedia

  • Christmas in the post-War United States — New Orleans department store Santa Claus, 1954 Christmas in the United States during the post War years (1946–1964) reflected a period of peace, productivity, and prosperity. Americans staged sumptuous Christmases and enjoyed a variety of holiday …   Wikipedia

  • police whistle — Synonyms and related words: Klaxon, Mayday, Roman candle, SOS, aid to navigation, air raid alarm, alarm, alarm bell, alarm clock, alarm signal, alarum, alert, all clear, amber light, balefire, beacon, beacon fire, bell, bell buoy, blinker,… …   Moby Thesaurus

  • signal post — A post along a railroad track indicating the necessity of giving a signal at that point, especially a whistle for a railroad crossing …   Ballentine's law dictionary