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Definition: Speed Limit |
Speed LimitNoun1. Regulation establishing the top speed permitted on a given road. Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
(From Wikipedia, the free Encyclopedia)
A speed limit is the maximum speed of travel permitted by a vehicle on a road by law. Speed limits are applied elsewhere on different modes of transport e.g. on stretches of railroad, on boats in harbours, some bicycle routes, etc.
Speed limits vary by type of road, including the number of lanes. Residential streets, with primarily an access function, typically have much lower maximum speeds than intercity roads, with primarily a movement function.
Signage
Speed limits are usually marked with a speed limit sign.
''International speed limit sign
United States speed limit sign
Note: In Canada in kilometres per hour (and with the term "maximum" in front) and in United States in miles per hour (Oregon has dropped the word "limit" from speed limit signs, and in California, most signs use "Maximum Speed" instead of "Speed Limit")
(In Canada units are given, and in the US at the first few signs upon entering the country)
Design Speed
Speed limits are generally peripherally related to the design speed of the road, which is "a selected speed used to determine the various geometric design features of the roadway." according to the 2001 AASHTO Green Book, the highway design manual. It has been changed from previous versions which considered it the "maximum safe speed that can be maintained over a specific section of highway when conditions are so favorable that the design features of the highway govern."
85th Percentile Rule
Traffic engineers are taught the 85th Percentile Rule, which claims that maximum speed limits should be set at a speed at and above what 85% vehicles are driving. (Thus 15% of vehicles are speeding). This rule has been used for many years, yet no scientific evidence has been produced that this particular rule is safer than any other.
Speed Limits on United States Interstate Highways
On interstate highways in the United States speed limits range from 55 mi/h to 75 mi/h (about 88 km/h to 121 km/h). Before the 1973 energy crisis, some states posted no speed limit on the interstate highways. In 1974, Congress imposed a nationwide 55 mi/h (88 km/h) speed limit by threatening to withhold highway funds from states that did not adopt this limit. It was estimated that a speed of 55 mi/h used 17% less fuel per mile than a speed of 75 mi/h. This limit was unpopular, especially in Western states. In 1987 states were permitted to raise speed limits to 65 mi/h (104 km/h) on rural interstate highways. The federal restriction on speed limit was lifted on November 28, 1995, leaving speed setting to the states. All states except Montana imposed numerical speed limits (Montana had a "reasonable and prudent" speed limit before and after, until 2000 when Interstates were generally posted at 75 mi/h), many higher than 65 mi/h. However, no Interstate Highway or express way is signed for over 75 mi/h, and within Major City Limits, few are over 65 mi/h. South Carolina raised the speed limit to 70 mi/h in 1999, but the 65 mi/h speed limit is used on certain Interstate highways.
In addition to the legally defined maximum speed, there is often also a minimum speed on certain roads. Vehicles are expected to travel above 40 mi/h (about 72 km/h) under normal conditions. However, most states do not state this nor enforce it.
Safety
The question of speed limits and safety is also an important one. It is argued that lower speeds save lives. Vehicles crashing at slow speeds rarely cause deaths. However, the evidence from raising speed limits in the 1980s and 1990s found mixed empirical evidence. While there were more fatalities on the interstate roads immediately affected, overall roadway death rates went down. This is because high speed drivers switched from even more dangerous non-interstate facilities to interstates, now that the risk of being caught for speeding was diminished. Thus fatal accidents on non-interstates were reduced. Others argue that it is speed variance that kills, and accidents are caused by vehicles traveling at very different speeds. (Vehicles traveling the same speed in the same lane will not crash).
However, unrealistically (or unreasonably) low speed limits, especially interstate, lead to disrespect for the law, contempt of law enforcement, and high difference between faster and slower drivers. They will make violators out of citizens who would be otherwise law-abiding. If the posted speed limit is unrealistically low, most vehicles, according to the 85th percentile rule, will ignore the sides while only a few will abide by the posted limits.
Roads without speed limits
There still remain a few public roads where speed limits do not apply. The most famous of these are German intercity Autobahns. The Northern Territory, Australia also has no blanket speed limits outside major towns. Traffic levels on the Territory's roads are extremely light.
See also
- hierarchy of road,
- interstate highway,
- Speed trap,
- Road-rule enforcement camera
An axiom of Einstein's relativity theories states that the speed limit of the Universe is Light speed, 2.99792458 × 108 metres per second.
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Speed limit."
Crosswords: Speed Limit |
| English words defined with "speed limit": speed demon, speeder, speeding ticket. (references) |
| Specialty definitions using "speed limit": BU road, built-up road ♦ civil speed, CROOK ♦ maximum authorised speed, MERCURY ♦ NBU road, non built-up road ♦ posted speed. (references) |
| Domain | Usage | |
Lyrics | Don't let that speed limit slow you down (Run; performing artist: George Strait) | |
Movie/TV Titles | Speed Limit (1926) The Speed Limit (1913) Matrimony's Speed Limit (1913) | |
Source: compiled by the editor from various references; see credits. | ||
| Thumbnail | Description & Credit | Thumbnail | Description & Credit |
 | Erosion - ironically below a sign stating boat speed limit to minimize wake and erosion. Credit: America's Coastlines. |  | Highway through Chicago, Illinois. Sign showing speed limit and U.S. Route No. 12. Two cars in background. Credit: Library of Congress. |
Source: pictures compiled by the editor from various references; see picture credits. | |||
| Subject | Topic | Quote |
Travel | Netherlands | The speed limit in the cities is 30 miles (50 km) per hour and on highways about 75 miles (120 km) per hour. (references) |
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
Expressions using "speed limit": break the speed limit ♦ exceed the speed limit ♦ exceeding the speed limit ♦ speed limit for a shockless functioning ♦ variable speed limit and enforcement. Additional references. | |
| Source: compiled by the editor from various references; see credits. |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Expression | Frequency per Day |
speed limit | 110 |
speed limit sign | 47 |
highway speed limit | 9 |
speed limit law | 5 |
| Source: compiled by the editor from various references; see credits. | |
| Language | Translations for "speed limit"; alternative meanings/domain in parentheses. | |
Afrikaans | snelheidsgrens (speed, speed-limit). (various references) | |
Albanian | shpejtësi maksimale e lejuar. (various references) | |
Arabic | تحديد السرعة. (various references) | |
Bulgarian | максималната позволена скорост. (various references) | |
Czech | nejvyšší dovolená rychlost. (various references) | |
Danish | hastighedsgrænse (speed-limit). (various references) | |
Dutch | snelheidsgrens (speed-limit). (various references) | |
Esperanto | rapidlimo (speed-limit). (various references) | |
Finnish | sallittu ajonopeus, nopeusrajoitus (restriction of speed). (various references) | |
French | limitation de vitesse (speed restriction). (various references) | |
German | geschwindigkeitsbegrenzung (limit, speed restriction). (various references) | |
Greek | όριο ταχύτητασ, όριο ταχύτητας (the speed limit). (various references) | |
Hungarian | megengedett sebesség (regulation speed). (various references) | |
Italian | limite di velocit . (various references) | |
Japanese Kanji | スパイ罪 (crime of espionage, fastball, ink spattering, slowing down, spaghetti, spaghetti meat sauce, spaghetti Western, span, span of control, spangle, Spanish, Spanish America, spanner, Spartacus Games, spasm, spats, spatula, speaker, speaker unit, speech, speech therapist, speech therapy, speed, speed ball, speed skating, speed up, speed-gun, speedometer, speedway, speedy, spot, student slang for the restaurant chain "Spaghetti Factory", thank you, wrench), 制限速度 . (various references) | |
Japanese Katakana | せい'"そくど, ス"ードリミット . (various references) | |
Manx | cagliagh bieauid. (various references) | |
Norwegian | fartsgrense (speed-limit). (various references) | |
Pig Latin | eedspay imitlay.(various references) | |
Portuguese | velocidade limite de funcionamento sem choque (speed limit for a shockless functioning), velocidade limite de aderência total (speed limit providing total adhesion). (various references) | |
Russian | ограничение скорости, дозволенная скорость. (various references) | |
Serbo-Croatian | ograničenje brzine. (various references) | |
Spanish | velocidad máxima (maximum speed). (various references) | |
Swedish | hastighetsbegränsning. (various references) | |
Turkish | hız limiti, azami sürat. (various references) | |
Ukrainian | дозволена швидкість. (various references) | |
| Source: compiled by the editor from various translation references. | ||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "d-e-e-i-i-l-m-p-s-t" | |
-1 letter: dimpliest. | |
-2 letters: delimits, itemised, limiteds. | |
-3 letters: deities, delimes, delimit, despite, dimples, elitism, elmiest, emptied, empties, epistle, impedes, implied, implies, itemise, limiest, limited, limites, limpest, limpets, lipides, mildest, misedit, mispled, pelites, pelmets, pestled, pieties, pietism, septime, smelted, speiled, spieled, stimied, templed, temples. | |
-4 letters: delime, delist, demies, demise, demits, diesel, dimple, dispel, distil, ediles, eldest, elemis. | |
| Words containing the letters "d-e-e-i-i-l-m-p-s-t" | |
+4 letters: epidemiologist. | |
+5 letters: epidemiologists, lymphadenitises, poliomyelitides. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
| 1. Definition 2. Crosswords 3. Usage: Modern 4. Images: Slideshow | 5. Images: Photo Album 6. Quotations: Non-fiction 7. Expressions 8. Expressions: Internet | 9. Translations: Modern 10. Anagrams 11. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
