Missouri: Is it legal to put a train horn on a car?
Missouri allows a horn or whistle but bars unnecessary noise and any other sound-producing signaling device, which may cover an added train horn.
Missouri requires a forward-facing horn or whistle loud enough to warn others, and it may be used only for warning. The law also says no other sound-producing signaling device may be used at any time. That arguably bars an extra train horn alongside the factory horn, but the statute doesn't name air or train horns, and there is no decibel limit. Missouri's law is unusual in naming a whistle as an acceptable signaling device.
Conditions
- Horn may be used for warning purposes only
- No other sound-producing signaling device may be used
What the law says
Every motor vehicle shall be equipped with a horn, directed forward, or whistle in good working order, capable of emitting a sound adequate in quantity and volume to give warning of the approach of such vehicle to other users of the highway and to pedestrians. Such signaling device shall be used for warning purposes only and shall not be used for making any unnecessary noise, and no other sound-producing signaling device shall be used at any time.
Sources
- RSMo § 307.170.1 Official · revisor.mo.gov
Confirm with the state
- Agency
- Missouri State Highway Patrol
- Phone
- 573-751-3313
- Website
- mshp.dps.missouri.gov
How bordering states compare
- Arkansas Allowed with limitsArkansas has no train horn ban, but no horn may make an unreasonably loud or harsh sound or a whistle.
- Illinois Allowed with limitsIllinois bans horns that make an unreasonably loud or harsh sound or a whistle, which a typical train horn likely fails.
- Iowa Allowed with limitsIowa bans horns that make an unreasonably loud or harsh sound or a whistle, which a typical train horn likely fails.
- Kansas Allowed with limitsKansas bans horns that make an unreasonably loud or harsh sound or whistle, which a typical train horn likely fails.
- Kentucky Allowed with limitsKentucky sets no horn loudness limit but bars sirens, whistles, and bells on non-emergency vehicles.
- Nebraska Allowed with limitsNebraska bans sirens and exhaust whistles on vehicles and bars unnecessary or unreasonably loud or harsh horn use, which likely covers train horns.
- Oklahoma Allowed with limitsOklahoma has no express train-horn ban, but no horn or warning device may emit an unreasonably loud or harsh sound.
- Tennessee Allowed with limitsTennessee bans sirens and exhaust, compression or spark plug whistles, and forbids unreasonably loud or harsh horn sounds, without naming air horns.