Whistle post

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Whistle posts advise locomotive engineers where to begin sounding the horn.
Whistle posts advise locomotive engineers where to begin sounding the horn.

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.

Contents

[edit] United States

Whistle posts in the United States were traditionally placed about one-quarter mile in advance of a road crossing.

Whistle post as used by the Southern Railway.
Whistle post as used by the Southern Railway.

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'.[1] 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.

A whistle post on the Norfolk Southern line in Battle Creek, MI.
A whistle post on the Norfolk Southern line in Battle Creek, MI.

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Whistle post which protects multiple grade crossings.
Whistle post which protects multiple grade crossings.

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.

[edit] 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.

[edit] Republic of Ireland

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

[edit] France

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.

[edit] Germany

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).

[edit] Poland

A whistle board on the approach to a level crossing at Somonino, Poland.
A whistle board on the approach to a level crossing at Somonino, Poland.

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.

[edit] 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.

[edit] References

  1. ^ (28 April, 1968) Rules for conducting transportation, The official employee operators manual. Penn Central Railroad.