when do trains have to blow their horns
Train horn On April 27, 2005, the Federal Railroad Administration (FRA), which enforces rail safety regulations, published the final rule on the use of locomotive horns at highway-rail grade crossings.[4][5] Effective June 24, 2005, the rule requires that locomotive horns be sounded at all public grade crossings at least 15 seconds, but not more than 20 seconds before entering a crossing.[6] This rule applies when the train speed is below 45 mph (70 km/h). At 45 mph or above, trains are still required to sound their horn at the designated location (usually denoted with a whistle post).
French horn A classical orchestra usually contained two horns. Typically, the 1st horn played a high part and the 2nd horn played a low part. Composers from Beethoven onwards commonly used four horns. Here, the 1st and 2nd horns played as a pair (1st horn being high, 2nd horn being low), and the 3rd and 4th horns played as another pair (3rd horn being high, 4th horn being low). Music written for the modern horn follows a similar pattern with 1st and 3rd horns being high and 2nd and 4th horns being low. This configuration serves multiple purposes. It is easier to play high when the adjacent player is playing low and vice versa. Pairing makes it easier to write for horns, as the 3rd and 4th horns can take over from the 1st and 2nd horns or play contrasting material. For example, if the piece is in C minor, the 1st and 2nd horns might be in C, the tonic major key, which could get most of the notes, and the 3rd and 4th horns might be in Eâ™­, the relative major key, to fill in the gaps. Many orchestral horn sections today also have an assistant[17] who doubles the 1st horn part for selected passages, joining in loud parts, playing instead of the principal if there is a 1st horn solo approaching, or alternating with the principal if the part is tiring to play.[18] Often the assistant is asked to play a passage after resting a long time. Also, he or she may be asked to enter in the middle of a passage, exactly matching the sound, articulation, and overall interpretation of the principal.