905.2 Traffic Studies - Revision history

Smithk: Per TS, updated text to current verbiage by changing "accidents" to "crashes", "SWAR" changed to "SWCR" and "AR" to "CR".

2022-04-13T14:22:35Z

Per TS, updated text to current verbiage by changing "accidents" to "crashes", "SWAR" changed to "SWCR" and "AR" to "CR".

Smithk: updated broken link

2022-03-08T17:04:14Z

updated broken link

← Older revision		Revision as of 12:04, 8 March 2022
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	\|[[image:905.4.11.1.jpg\|right\|140px]]\|\|[[image:905.4.11.2.jpg\|right\|140px]]\|\|[[image:905.4.11.3.jpg\|right\|140px]]		\|[[image:905.4.11.1.jpg\|right\|140px]]\|\|[[image:905.4.11.2.jpg\|right\|140px]]\|\|[[image:905.4.11.3.jpg\|right\|140px]]
	\|}		\|}
	Law enforcement at a location can reduce the number and severity of crashes, provide orderly flow of traffic and detect offenders of traffic violations. When considering law enforcement as a countermeasure, several options are available including contacting [http://~~wwwi~~/~~intranet~~/hs/ Highway Safety and Traffic] or the regional [https://www.savemolives.com/mcrs Blueprint] representative, the local law enforcement agency direct or consider automated enforcement options. Crashes that do not have a direct engineering solution should not be disregarded. [http://sp/sites/ts/Pages/default.aspx Highway Safety and Traffic] provides law enforcement agencies contracts to enforce hazardous moving violations and driving under the influence of alcohol violations. Law enforcement should also be considered for work zones. Refer to [[616.16 Law Enforcement Services\|EPG 616.16 Law Enforcement Services]] when considering law enforcement in work zones.		Law enforcement at a location can reduce the number and severity of crashes, provide orderly flow of traffic and detect offenders of traffic violations. When considering law enforcement as a countermeasure, several options are available including contacting [http://sp/sites/ts/Pages/default.aspx Highway Safety and Traffic] or the regional [https://www.savemolives.com/mcrs Blueprint] representative, the local law enforcement agency direct or consider automated enforcement options. Crashes that do not have a direct engineering solution should not be disregarded. [http://sp/sites/ts/Pages/default.aspx Highway Safety and Traffic] provides law enforcement agencies contracts to enforce hazardous moving violations and driving under the influence of alcohol violations. Law enforcement should also be considered for work zones. Refer to [[616.16 Law Enforcement Services\|EPG 616.16 Law Enforcement Services]] when considering law enforcement in work zones.

	===905.2.12 Traffic Calming===		===905.2.12 Traffic Calming===

Smithk: /* 905.2.14 Speed Limit Guidelines */

2021-04-27T17:54:20Z

905.2.14 Speed Limit Guidelines

← Older revision		Revision as of 12:54, 27 April 2021
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	The following guidelines promote consistency of speed limit postings on the state of Missouri’s highway system. In all cases, engineering judgment is necessary to determine the most appropriate speed limit at a location.		The following guidelines promote consistency of speed limit postings on the state of Missouri’s highway system. In all cases, engineering judgment is necessary to determine the most appropriate speed limit at a location.


	====905.2.14.1 Maximum Speed Limits====		====905.2.14.1 Maximum Speed Limits====

Smithk: Per TS, minor clarifications

2021-04-27T17:53:02Z

Per TS, minor clarifications

Show changes

Smithk: Per TS, moved EPG 949.2 Speed Limit Guidelines (where it had been largely unchanged since Feb. 11, 2010; after being updated and moved from EPG 949.2 Prevailing Speed Determination) to EPG 905.2.14

2021-04-27T17:47:08Z

Per TS, moved EPG 949.2 Speed Limit Guidelines (where it had been largely unchanged since Feb. 11, 2010; after being updated and moved from EPG 949.2 Prevailing Speed Determination) to EPG 905.2.14

Show changes

Smithk: /* 905.2.13 Voiding City Ordinances on State Routes with Inappropriate Speed Limits */ Per TS, minor clarifications

2021-04-27T17:16:46Z

905.2.13 Voiding City Ordinances on State Routes with Inappropriate Speed Limits: Per TS, minor clarifications

← Older revision		Revision as of 12:16, 27 April 2021
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	===905.2.13 Voiding City Ordinances on State Routes with Inappropriate Speed Limits===		===905.2.13 Voiding City Ordinances on State Routes with Inappropriate Speed Limits===
	[[image:949.1.jpg\|right\|300px]]		[[image:949.1.jpg\|right\|300px]]
	~~Paragraph~~ 4 of ~~House Bill 1047~~ of the ~~88<sup>th</sup> General Assembly states~~ that the ~~Commission~~ may declare any ordinance void if it finds that ordinance is:		[https://revisor.mo.gov/main/OneSection.aspx?section=304.010 Missouri Revised Statute 304.010] contains the state laws pertaining to speed limits on Missouri’s roadways. Paragraphs 3 and 4 address speed limits on state routes and state:
			:''3. On any state road or highway where the speed limit is not set pursuant to a local ordinance, the highways and transportation commission may set a speed limit higher or lower than the uniform maximum speed limit provided in subsection 2 of this section, if a higher or lower speed limit is recommended by the department of transportation. The department of public safety, where it believes for safety reasons, or to expedite the flow of traffic a higher or lower speed limit is warranted, may request the department of transportation to raise or lower such speed limit, except that no speed limit shall be set higher than seventy miles per hour.
			:''4. Notwithstanding the provisions of section 304.120 or any other provision of law to the contrary, cities, towns and villages may regulate the speed of vehicles on state roads and highways within such cities', towns' or villages' corporate limits by ordinance with the approval of the state highways and transportation commission. Any reduction of speed in cities, towns or villages shall be designed to expedite the flow of traffic on such state roads and highways to the extent consistent with public safety. The commission may declare any ordinance void if it finds that such ordinance is:
			::''(1) Not primarily designed to expedite traffic flow; and
			::''(2) Primarily designed to produce revenue for the city, town or village which enacted such ordinance.

	:1. ~~Not primarily designed to expedite traffic flow; and~~		:''If an ordinance is declared void, the city, town or village shall have any future proposed ordinance approved by the highways and transportation commission before such ordinance may take effect.''

	~~:2. Primarily designed to produce revenue for the city, town or village that enacted the ordinance.~~		If a District Engineer believes that a city, village or town has passed an ordinance establishing an inappropriate speed limit, the District Engineer shall ensure the following actions are taken:

	If a District Engineer believes that a city, village or town has ~~enacted such~~ an ordinance, the District Engineer shall ensure the following actions are taken:

	:1. Advise the city that a study will be made to determine the appropriate speed limit in the area.		:1. Advise the city that a study will be made to determine the appropriate speed limit in the area.

Smithk: Per TS, moved EPG 949.1 Voiding City Ordinances on State Routes with Inappropriate Speed Limits (where it had been unchanged since it was new Jan. 16, 2008) to EPG 905.2.13

2021-04-27T17:10:41Z

Per TS, moved EPG 949.1 Voiding City Ordinances on State Routes with Inappropriate Speed Limits (where it had been unchanged since it was new Jan. 16, 2008) to EPG 905.2.13

@@ Line 104: / Line 104: @@
 :* crash rates and
 :* enforcement.
 [[Category:905 Traffic Studies]]

Smithk: Per TS, numerous minor clarifications

2020-10-14T17:19:40Z

Per TS, numerous minor clarifications

← Older revision		Revision as of 12:19, 14 October 2020
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	:* transit.		:* transit.

	[http://tmshome TMS] has ~~also developed~~ a highway capacity analysis tool.		[http://tmshome TMS] has a highway capacity analysis tool.

	===905.2.2 Crash Analysis===		===905.2.2 Crash Analysis===
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	A crash analysis is performed for a traffic study to determine whether a safety or operational problem exists. Crash information is obtained during the [[905.1 Traffic Data Collection\|data collection]] phase of the traffic study. Crashes are reviewed for severity level of crashes as well as total number of crashes. A high number of crashes having no severe crashes typically indicates a location with high traffic volumes and a potential capacity or operational issue. A location with severe crashes should be reviewed for sight distance, signing, signal timing or other roadway features that may be leading to improper driver behavior. When performing a crash analysis, look for crash patterns that may lead to easily recognizable countermeasures. A collision diagram helps to identify crash patterns.		A crash analysis is performed for a traffic study to determine whether a safety or operational problem exists. Crash information is obtained during the [[905.1 Traffic Data Collection\|data collection]] phase of the traffic study. Crashes are reviewed for severity level of crashes as well as total number of crashes. A high number of crashes having no severe crashes typically indicates a location with high traffic volumes and a potential capacity or operational issue. A location with severe crashes should be reviewed for sight distance, signing, signal timing or other roadway features that may be leading to improper driver behavior. When performing a crash analysis, look for crash patterns that may lead to easily recognizable countermeasures. A collision diagram helps to identify crash patterns.

	When calculating crash rates during the analysis, compare the calculated rate to the statewide rate. Typically non-intersection studies are compared by roadway type. Comparisons by roadway type are a better indication of a roadway’s safety than comparisons by route designation. For instance, a rural county lettered route functions differently from Rte. D (Page Ave.) in St. Louis County. It is also important to compare routes by urban/rural classifications. For most routes, a crash rate is considered poor when it starts to reach double the statewide average.		When calculating crash rates during the analysis, compare the calculated rate to the statewide rate. Typically, non-intersection studies are compared by roadway type. Comparisons by roadway type are a better indication of a roadway’s safety than comparisons by route designation. For instance, a rural county lettered route functions differently from Rte. D (Page Ave.) in St. Louis County. It is also important to compare routes by urban/rural classifications. For most routes, a crash rate is considered poor when it starts to reach double the statewide average.

	~~===905.2.3 Countermeasure Selection===~~
	{\|style="padding: 0.3em; margin-left:7px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="400px" align="right"		{\|style="padding: 0.3em; margin-left:7px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="400px" align="right"
	\|-		\|-
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	\|[http://www.cmfclearinghouse.org/ Crash Modification Factor (CMF) Clearinghouse] presents proven countermeasures, the most important of which show up in the HSM		\|[http://www.cmfclearinghouse.org/ Crash Modification Factor (CMF) Clearinghouse] presents proven countermeasures, the most important of which show up in the HSM
	\|}		\|}
	The selection of countermeasures is covered in AASHTO's [http://www.highwaysafetymanual.org/ Highway Safety Manual] and [http://~~safety~~.~~transportation~~.org/~~guides~~.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible.		===905.2.3 Countermeasure Selection===

			The selection of countermeasures is covered in AASHTO's [http://www.highwaysafetymanual.org/ Highway Safety Manual] and [http://www.trb.org/Main/Blurbs/152868.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible.
	[[image:905.4.4.jpg\|right\|300px]]		[[image:905.4.4.jpg\|right\|300px]]

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	:* Legibility, especially the size and font of lettering		:* Legibility, especially the size and font of lettering
	:* Perception-reaction time		:* Perception-reaction time
	:* Driver overload, that is, ~~concentrating~~ too much information for a driver to reasonably ~~accommodate~~		:* Driver overload, that is, too much information too quickly for a driver to reasonably understand
	:* The number of lines of legend		:* The number of lines of legend
	:* Advance placement of signing/delineation		:* Advance placement of signing/delineation
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	===905.2.9 Traffic Control in School Areas===		===905.2.9 Traffic Control in School Areas===

	When reviewing traffic control in school areas, refer to [[902.11 Traffic Control for Schools\|EPG 902.11 Traffic Control for Schools]]. Another source of information involving traffic and pedestrian operations in school areas is the manual ~~[http://www.safetycenter.cmsu.edu/publications/schooltransportation.html~~ ''School Transportation & Traffic Safety – Guidebook for Local Agencies''] that was published for local agencies in 1996 using TTAP funds. Any information from the guidebook is secondary to the EPG.		When reviewing traffic control in school areas, refer to [[902.11 Traffic Control for Schools\|EPG 902.11 Traffic Control for Schools]]. Another source of information involving traffic and pedestrian operations in school areas is the manual ''School Transportation & Traffic Safety – Guidebook for Local Agencies'' that was published for local agencies in 1996 using TTAP funds. Any information from the guidebook is secondary to the EPG.

	===905.2.10 Pedestrian and Bicycle Facilities===		===905.2.10 Pedestrian and Bicycle Facilities===
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	\|[[image:905.4.11.1.jpg\|right\|140px]]\|\|[[image:905.4.11.2.jpg\|right\|140px]]\|\|[[image:905.4.11.3.jpg\|right\|140px]]		\|[[image:905.4.11.1.jpg\|right\|140px]]\|\|[[image:905.4.11.2.jpg\|right\|140px]]\|\|[[image:905.4.11.3.jpg\|right\|140px]]
	\|}		\|}
	Law enforcement at a location can reduce the number and severity of crashes, provide orderly flow of traffic and detect offenders of traffic violations. When considering law enforcement as a countermeasure, several options are available including contacting [http://wwwi/intranet/hs/ Highway Safety] or the regional Blueprint representative, the local law enforcement agency direct or consider automated enforcement options. Crashes that do not have a direct engineering solution should not be disregarded. [http://~~www.modot.mo.gov~~/~~safety~~/ Highway Safety] provides law enforcement agencies contracts to enforce hazardous moving violations and driving under the influence of alcohol violations. Law enforcement should also be considered for work zones. Refer to [[616.16 Law Enforcement Services\|EPG 616.16 Law Enforcement Services]] when considering law enforcement in work zones.		Law enforcement at a location can reduce the number and severity of crashes, provide orderly flow of traffic and detect offenders of traffic violations. When considering law enforcement as a countermeasure, several options are available including contacting [http://wwwi/intranet/hs/ Highway Safety and Traffic] or the regional [https://www.savemolives.com/mcrs Blueprint] representative, the local law enforcement agency direct or consider automated enforcement options. Crashes that do not have a direct engineering solution should not be disregarded. [http://sp/sites/ts/Pages/default.aspx Highway Safety and Traffic] provides law enforcement agencies contracts to enforce hazardous moving violations and driving under the influence of alcohol violations. Law enforcement should also be considered for work zones. Refer to [[616.16 Law Enforcement Services\|EPG 616.16 Law Enforcement Services]] when considering law enforcement in work zones.

	===905.2.12 Traffic Calming===		===905.2.12 Traffic Calming===
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	:* relocation of problems		:* relocation of problems
	:* noise		:* noise
	:* ~~accident~~ rates and		:* crash rates and
	:* enforcement.		:* enforcement.

Smithk: /* 905.2.3 Countermeasure Selection */ Per Traffic, removed archaic language

2014-07-08T14:37:38Z

905.2.3 Countermeasure Selection: Per Traffic, removed archaic language

← Older revision		Revision as of 09:37, 8 July 2014
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	===905.2.3 Countermeasure Selection===		===905.2.3 Countermeasure Selection===
	{\|style="padding: 0.3em; margin-left:7px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="~~360px~~" align="right"		{\|style="padding: 0.3em; margin-left:7px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="400px" align="right"
	\|-		\|-
	\|'''Additional Information'''		\|'''Additional Information'''
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	\|[http://www.cmfclearinghouse.org/ Crash Modification Factor (CMF) Clearinghouse] presents proven countermeasures, the most important of which show up in the HSM		\|[http://www.cmfclearinghouse.org/ Crash Modification Factor (CMF) Clearinghouse] presents proven countermeasures, the most important of which show up in the HSM
	\|}		\|}
	The selection of countermeasures is covered in AASHTO's [http://www.highwaysafetymanual.org/ Highway Safety Manual] and [http://safety.transportation.org/guides.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible. At the national level, there is a project underway to [http://www.trb.org/news/blurb_detail.asp?id=3012 develop a highway safety manual]. Much like the HAL Manual and NCHRP 500 series, the Highway Safety Manual will feature a chart of known problems with potential solutions to those problems.		The selection of countermeasures is covered in AASHTO's [http://www.highwaysafetymanual.org/ Highway Safety Manual] and [http://safety.transportation.org/guides.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible.
	[[image:905.4.4.jpg\|right\|300px]]		[[image:905.4.4.jpg\|right\|300px]]

Smithk: /* 905.2.3 Countermeasure Selection */

2014-07-08T14:19:45Z

905.2.3 Countermeasure Selection

← Older revision		Revision as of 09:19, 8 July 2014
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	===905.2.3 Countermeasure Selection===		===905.2.3 Countermeasure Selection===
			{\|style="padding: 0.3em; margin-left:7px; border:2px solid #a9a9a9; text-align:center; font-size: 95%; background:#f5f5f5" width="360px" align="right"
	The selection of countermeasures is covered in ~~the~~ [~~[907~~.~~5 HAL Manual\|HAL~~ Manual]] and [http://safety.transportation.org/guides.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible. At the national level, there is a project underway to [http://www.trb.org/news/blurb_detail.asp?id=3012 develop a highway safety manual]. Much like the HAL Manual and NCHRP 500 series, the Highway Safety Manual will feature a chart of known problems with potential solutions to those problems.		\|-
			\|'''Additional Information'''
			\|-
			\|[http://www.cmfclearinghouse.org/ Crash Modification Factor (CMF) Clearinghouse] presents proven countermeasures, the most important of which show up in the HSM
			\|}
			The selection of countermeasures is covered in AASHTO's [http://www.highwaysafetymanual.org/ Highway Safety Manual] and [http://safety.transportation.org/guides.aspx NCHRP 500 series]. Both of these documents should be used as reference tools only. Any information contained in these documents is considered secondary to the EPG. Both of these guides start with identified problems and use charts to match potential solutions to the identified problems. These charts are comprehensive but are not the only solutions possible. At the national level, there is a project underway to [http://www.trb.org/news/blurb_detail.asp?id=3012 develop a highway safety manual]. Much like the HAL Manual and NCHRP 500 series, the Highway Safety Manual will feature a chart of known problems with potential solutions to those problems.
	[[image:905.4.4.jpg\|right\|300px]]		[[image:905.4.4.jpg\|right\|300px]]

← Older revision		Revision as of 09:22, 13 April 2022
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	=====905.2.14.2.1 Fatality and Disabling Injury Crash Rate=====		=====905.2.14.2.1 Fatality and Disabling Injury Crash Rate=====
	If either the fatal or disabling injury crash rates, based on reportable ~~accidents~~ within the proposed area, are 50% higher than the statewide average crash rate for the same roadway type, prevailing speed may be reduced by 5%.		If either the fatal or disabling injury crash rates, based on reportable crashes within the proposed area, are 50% higher than the statewide average crash rate for the same roadway type, prevailing speed may be reduced by 5%.

	If the fatal or disabling crash rate is more than twice the statewide rate for the roadway type, the prevailing speed may be reduced by 10%.		If the fatal or disabling crash rate is more than twice the statewide rate for the roadway type, the prevailing speed may be reduced by 10%.
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	=====905.2.14.2.2 Total Crash Rate=====		=====905.2.14.2.2 Total Crash Rate=====
	If the overall crash rate, based on reportable ~~accidents~~ within the proposed area, is 50% higher than the statewide average crash rate for the same roadway type, prevailing speed may be reduced by 5%.		If the overall crash rate, based on reportable crashes within the proposed area, is 50% higher than the statewide average crash rate for the same roadway type, prevailing speed may be reduced by 5%.

	If the crash rate is more than twice the statewide rate for the roadway type, the prevailing speed may be reduced by 10%.		If the crash rate is more than twice the statewide rate for the roadway type, the prevailing speed may be reduced by 10%.
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	Where significant adjacent development includes residential and commercial access points, the prevailing speed may be reduced to account for driveway conflicts. If necessary, this effect on the prevailing speed may be determined as outlined below.		Where significant adjacent development includes residential and commercial access points, the prevailing speed may be reduced to account for driveway conflicts. If necessary, this effect on the prevailing speed may be determined as outlined below.

	The effect of driveway entrances can be determined by using a Driveway Conflict Number. For this purpose, a private or field entrance should have a Driveway Conflict Number of 1. Minor commercial entrances should have a number of 5. Major commercial entrances, shopping centers or industrial plant entrances that generate relatively high volumes of traffic, and public streets should have a number of 10. If the total Driveway Conflict Number exceeds a rate of 40 per mile through the proposed zone, the prevailing speed may be reduced by 5 percent. If the total number exceeds a rate of 60 per mile, the prevailing speed may be reduced by 10 percent. However, before a reduction is made due to the Driveway Conflict Number, the Poisson Curve should be used to determine if the ~~accident~~ reduction is statistically significant.		The effect of driveway entrances can be determined by using a Driveway Conflict Number. For this purpose, a private or field entrance should have a Driveway Conflict Number of 1. Minor commercial entrances should have a number of 5. Major commercial entrances, shopping centers or industrial plant entrances that generate relatively high volumes of traffic, and public streets should have a number of 10. If the total Driveway Conflict Number exceeds a rate of 40 per mile through the proposed zone, the prevailing speed may be reduced by 5 percent. If the total number exceeds a rate of 60 per mile, the prevailing speed may be reduced by 10 percent. However, before a reduction is made due to the Driveway Conflict Number, the Poisson Curve should be used to determine if the crash reduction is statistically significant.

	[[image:~~949~~.4.2 ~~Driveway Conflict~~.jpg\|center\|550px\|thumb\|<center>'''Figure 905.2.14.2.5'''</center>]]		[[image:905.2.14.2.5.jpg\|center\|550px\|thumb\|<center>'''Figure 905.2.14.2.5'''</center>]]

	The test is as follows:		The test is as follows:

	a) Consult Fig. 905.2.14.2.5, using the current number of ~~accidents~~ for the last year.		a) Consult Fig. 905.2.14.2.5, using the current number of crashes for the last year.

	b) Determine the graph’s percent value from the Poisson Curve.		b) Determine the graph’s percent value from the Poisson Curve.

	c) Compute ~~accident~~ rate for last year.		c) Compute crash rate for last year.

	::<math>\mbox{~~Accident~~ Rate}=\frac{\mbox{no. of crashes x 100,000,000}}		::<math>\mbox{Crash Rate}=\frac{\mbox{no. of crashes x 100,000,000}}
	{\mbox{365 x ADT x length in miles}}</math>		{\mbox{365 x ADT x length in miles}}</math>

	d) Obtain Statewide ~~Accident~~ Rate (~~SWAR~~). The ~~accident~~ data is obtained from the [http://tms/home/ Transportation Management System (TMS)].		d) Obtain Statewide Crash Rate (SWCR). The crash data is obtained from the [http://tms/home/ Transportation Management System (TMS)].

	e) Calculate percent reduction between ~~accident~~ rate and statewide ~~accident~~ rate by:		e) Calculate percent reduction between crash rate and statewide crash rate by:

	::<math>\mbox{Percent Reduction}={100}\frac{\mbox{AR-~~SWAR~~}}		::<math>\mbox{Percent Reduction}={100}\frac{\mbox{CR-SWCR}}
	{\mbox{AR}}</math>		{\mbox{CR}}</math>

	f) Compare % reduction with value obtained in step b.		f) Compare % reduction with value obtained in step b.
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	'''Example:'''		'''Example:'''

	:8.0-mile section of roadway, AADT = 3,100, 30 ~~accidents~~ within last year.		:8.0-mile section of roadway, AADT = 3,100, 30 crashes within last year.

	:a & b). Value obtained from Fig. 905.2.14.2 = 30 %		:a & b). Value obtained from Fig. 905.2.14.2 = 30 %

	:c).<math>\mbox{AR}=\mbox{331.4}=\frac{\mbox{30(100,000,000)}}		:c).<math>\mbox{CR}=\mbox{331.4}=\frac{\mbox{30(100,000,000)}}
	{\mbox{(365)(3,100)(8.0)}}</math>		{\mbox{(365)(3,100)(8.0)}}</math>

	:d). ~~SWAR~~ = 242.04		:d). SWCR = 242.04

	:e).<math>\mbox{26.9 percent reduction}={100}\frac{\mbox{331.4-242.04}}		:e).<math>\mbox{26.9 percent reduction}={100}\frac{\mbox{331.4-242.04}}
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	====905.2.14.3 Additional Guidelines for Establishing Speed Limits====		====905.2.14.3 Additional Guidelines for Establishing Speed Limits====
	Normally, isolated curves and turns, areas of restricted sight distance, no passing zones, etc. will not be considered as areas for lowering speed limits. The ~~accident~~ record on such highways will be the principle criterion. Advisory speed signs shall be used in connection with the appropriate warning signs at these locations.		Normally, isolated curves and turns, areas of restricted sight distance, no passing zones, etc. will not be considered as areas for lowering speed limits. The crash record on such highways will be the principle criterion. Advisory speed signs shall be used in connection with the appropriate warning signs at these locations.

	Except on divided highways, different speeds for traffic in opposite directions cannot be justified.		Except on divided highways, different speeds for traffic in opposite directions cannot be justified.