Category:612 Impact Attenuators - Revision history

Hoskir: updated per RR3849

2024-05-03T12:53:46Z

updated per RR3849

Hoskir: /* 612.1.4 MoDOT Equipment/Materials Stored in Bed of Protective Vehicle Guidelines */ updated per RR3779

2023-09-27T19:48:00Z

612.1.4 MoDOT Equipment/Materials Stored in Bed of Protective Vehicle Guidelines: updated per RR3779

← Older revision		Revision as of 14:48, 27 September 2023
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	===612.1.4 MoDOT Equipment/Materials Stored in Bed of Protective Vehicle Guidelines===		===612.1.4 MoDOT Equipment/Materials Stored in Bed of Protective Vehicle Guidelines===

	~~Loads~~ or cargo, such as sign posts or tools, ~~may be moved to and from work areas~~ in the bed of the protective vehicle~~/TMA, but must be removed when~~ protective vehicle~~/TMA~~ is deployed for protection or has the possibility of deployment prior to getting to the work area. Truck beds may be secured to the truck frame to maximize stability during impact. Steel plates and/or containers, secured by approved methods, may be used for ballast or weight to keep the dump bed against the host vehicle frame and may remain in the vehicle while the protective vehicle/TMA is deployed~~. Loads or cargo are not allowed to be carried on trailer type TMAs~~.		Protective vehicles may carry loads or cargo, such as sign posts or tools, in the bed of the protective vehicle. When the protective vehicle is being deployed for protection or has the possibility of deployment prior to getting to the work area, loads or cargo shall be properly secured. Loads or cargo are not allowed to be carried on TMAs.

			Truck beds may be secured to the truck frame to maximize stability during impact. Steel plates and/or containers, secured by approved methods, may be used for ballast or weight to keep the dump bed against the host vehicle frame and may remain in the vehicle while the protective vehicle/TMA is deployed.

	[[image:612.1.4.jpg\|center\|725px\|thumb\|<center>'''This bead container is securely fastened to the protective vehicle. The container is bolted through the bed of the truck. The container door is securely latched down.'''</center>]]		[[image:612.1.4.jpg\|center\|725px\|thumb\|<center>'''This bead container is securely fastened to the protective vehicle. The container is bolted through the bed of the truck. The container door is securely latched down.'''</center>]]


	===612.1.5 MoDOT Protective Vehicle/TMA Operator’s Training===		===612.1.5 MoDOT Protective Vehicle/TMA Operator’s Training===

Hoskir: /* 612.1.2 MoDOT Protective Vehicle/TMA Marking and Lighting */ updated per RR3725

2023-07-17T19:58:54Z

612.1.2 MoDOT Protective Vehicle/TMA Marking and Lighting: updated per RR3725

← Older revision		Revision as of 14:58, 17 July 2023
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	===612.1.2 MoDOT Protective Vehicle/TMA Marking and Lighting===		===612.1.2 MoDOT Protective Vehicle/TMA Marking and Lighting===
	~~'''Lighting.''' All lighting should be appropriately set~~, ~~depending~~ on the ~~day or nighttime conditions~~.		For future installations beginning July 1, 2023, use Emergency Alert Lights (EALs) on all TMAs in accordance with typical applications. Install EALs below the flashing arrow panel.

	~~The Light Bar may be used and the Emergency Alert lights~~ should be ~~used on the Rear Advanced Warning Truck for striping and sweeping operations and are optional on other mobile operations in accordance with typical applications. If used~~, ~~the rear facing amber/white Light Bar is installed~~ on ~~top of the vehicle and the Emergency Alert lights are installed below~~ the ~~flashing arrow panel~~.		All lighting should be appropriately set, depending on the day or nighttime conditions.

	If an approaching vehicle is observed driving in the occupied moving work zone lane, the TMA driver should activate the ~~Emergency Alert lights~~ by pushing the switch for a short duration. It is not recommended to leave the lights on very long because continuous or long term use may reduce the effectiveness of the ~~Emergency Alert lights.~~		If an approaching vehicle is observed driving in the occupied moving work zone lane, the TMA driver should activate the EALs by pushing the switch for a short duration. It is not recommended to leave the lights on very long because continuous or long term use may reduce the effectiveness of the EALs.

	'''Rear Face of TMA.''' The rear face of the attenuator device, when in the horizontal or operating position (protective mode), shall be marked with red and white retroreflective sheeting. The marking shall form a checkerboard pattern consisting of 12” by 12” red squares and 12” by 12” white squares spaced symmetrically starting from the top center.

	'''Vehicle Size.''' On MoDOT’s maintenance operations where the normal posted speed limit is 60 mph or greater, the protective vehicle shall be a Heavy-Duty Single Axle Truck style or heavier, and meet the truck-mounted and trailer-mounted attenuator manufacturer’s recommendations.

	'''Incident Response.''' For incident response operations, a vehicle with a truck/trailer-mounted attenuator is not required. If used, the host vehicle shall meet the truck/trailer-mounted attenuator manufacturer’s recommendations.

	===612.1.3 Protective Vehicle/TMA Operations===		===612.1.3 Protective Vehicle/TMA Operations===

Hoskir: updated 612.1.1 from MASH to MASH 2016

2022-09-21T19:35:34Z

updated 612.1.1 from MASH to MASH 2016

← Older revision		Revision as of 14:35, 21 September 2022
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	Damaged TMAs are to be removed from service and either repaired or replaced.		Damaged TMAs are to be removed from service and either repaired or replaced.

	NCHRP 350 and MASH crash-tests straight-on and offset collisions, not side impacts. TMAs are not designed for side impacts.		NCHRP 350 and MASH 2016 crash-tests straight-on and offset collisions, not side impacts. TMAs are not designed for side impacts.

	Articles on MoDOT's [[612.4 Maintenance Planning Guidelines for Impact Attenuators\|Maintenance Planning Guidelines for Impact Attenuators]] are available upon request.		Articles on MoDOT's [[612.4 Maintenance Planning Guidelines for Impact Attenuators\|Maintenance Planning Guidelines for Impact Attenuators]] are available upon request.

Legged1: erratum

2022-06-27T19:38:24Z

erratum

← Older revision		Revision as of 14:38, 27 June 2022
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	'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it has not frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.		'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it has not frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.
	<div id="Work Zone Crash Cushions"></div>		<div id="Work Zone Crash Cushions"></div>
	'''Work Zone Crash Cushions (for Sec 612.4.2).''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of crash cushion the contractor is using. When inspecting the work zone crash cushion, make sure that the crash cushion is in the location as shown on the temporary traffic control plans and set up in accordance with the manufacturer’s recommendations. If the crash cushion is water-filled, MoDOT requires a mixture content per manufacturer’s recommendations so that the crash cushion will not freeze and create a safety hazard. During periods of extended cold weather, the crash cushion(s) should be checked periodically to make sure it has not frozen. If this condition is found, the contractor will need to correct and/or replace the mixture. In the event the work zone crash cushion is damaged and needs to be replaced, it is considered incidental and replaced at no cost to the Commission.		'''Work Zone Crash Cushions (for Sec 612.4.3).''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of crash cushion the contractor is using. When inspecting the work zone crash cushion, make sure that the crash cushion is in the location as shown on the temporary traffic control plans and set up in accordance with the manufacturer’s recommendations. If the crash cushion is water-filled, MoDOT requires a mixture content per manufacturer’s recommendations so that the crash cushion will not freeze and create a safety hazard. During periods of extended cold weather, the crash cushion(s) should be checked periodically to make sure it has not frozen. If this condition is found, the contractor will need to correct and/or replace the mixture. In the event the work zone crash cushion is damaged and needs to be replaced, it is considered incidental and replaced at no cost to the Commission.

Smithk: Per DE and TS, guidance now reflects that the use of non-MASH 2016 temporary traffic control devices barriers is being discontinued. All temporary traffic control devices on a project must be NCHRP 350 or MASH 2016 Test Level 3 compliant.

2022-04-19T14:56:43Z

Per DE and TS, guidance now reflects that the use of non-MASH 2016 temporary traffic control devices barriers is being discontinued. All temporary traffic control devices on a project must be NCHRP 350 or MASH 2016 Test Level 3 compliant.

← Older revision		Revision as of 09:56, 19 April 2022
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	[[image:612.1 Trailer-type TMAs.jpg\|left\|275px\|thumb\|<center>'''Trailer-Mounted Attenuator'''</center>]]		[[image:612.1 Trailer-type TMAs.jpg\|left\|275px\|thumb\|<center>'''Trailer-Mounted Attenuator'''</center>]]

	The National Cooperative Highway Research Project 350 (NCHRP 350) and AASHTO Manual for Assessing Safety Hardware (MASH) set the crash criteria for TMAs. TMAs purchased by MoDOT meet these requirements.		The National Cooperative Highway Research Project 350 (NCHRP 350) and the 2016 AASHTO Manual for Assessing Safety Hardware (MASH 2016) set the crash criteria for TMAs. TMAs purchased by MoDOT meet these requirements.

	Damaged TMAs are to be removed from service and either repaired or replaced.		Damaged TMAs are to be removed from service and either repaired or replaced.
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	'''Material (for Sec 612.2)''' Certifications are to be collected on both the sand and retroreflective sheeting used in or on the sand-filled impact attenuators.		'''Material (for Sec 612.2)''' Certifications are to be collected on both the sand and retroreflective sheeting used in or on the sand-filled impact attenuators.

	'''Safety Requirements (for Sec 612.3)''' The inspector is to request a copy of the manufacturer’s certification that states the units comply with the crash test requirements of NCHRP 350 or MASH, Test Level 3~~, and have FHWA acceptance~~. This information is to be kept in the project files.		'''Safety Requirements (for Sec 612.3)''' The inspector is to request a copy of the manufacturer’s certification that states the units comply with the crash test requirements of NCHRP 350 or MASH 2016, Test Level 3. This information is to be kept in the project files.

	'''Truck-Mounted Attenuator (for Sec 612.4.1)''' TMAs are to be inspected to make sure they are structurally sound, the frames are not bent and that they appear to be in good working order. In some cases, the contractor may elect to add TMAs when TMAs are not required. Elective TMAs need to be NCHRP 350 or MASH, Test Level 3, compliant so the certification still needs to be collected. Typically, TMAs are only required and paid for under conditions where the contractor is operating without a lane drop set up (cones, channelizers, etc.). TMAs ~~that~~ the contractor voluntarily adds to an operation are typically not paid for.		'''Truck-Mounted Attenuator (for Sec 612.4.1)''' TMAs are to be inspected to make sure they are structurally sound, the frames are not bent and that they appear to be in good working order. In some cases, the contractor may elect to add TMAs when TMAs are not required. Elective TMAs need to be NCHRP 350 or MASH 2016, Test Level 3 compliant and therefore the certification still needs to be collected. Typically, TMAs are only required and paid for under conditions where the contractor is operating without a lane drop set up (cones, channelizers, etc.). TMAs the contractor voluntarily adds to an operation are typically not paid for.
	<div id="Sand-Filled Impact Attenuator Array"></div>		<div id="Sand-Filled Impact Attenuator Array"></div>
	'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it ~~hasn’t~~ frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.		'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it has not frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.
	<div id="Work Zone Crash Cushions"></div>		<div id="Work Zone Crash Cushions"></div>
	'''Work Zone Crash Cushions (for Sec 612.4.3).''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of crash cushion the contractor is using. When inspecting the work zone crash cushion, make sure that the crash cushion is in the location as shown on the temporary traffic control plans and set up in accordance with the manufacturer’s recommendations. If the crash cushion is water-filled, MoDOT requires a mixture content per manufacturer’s recommendations so that the crash cushion will not freeze and create a safety hazard. During periods of extended cold weather, the crash cushion(s) should be checked periodically to make sure it has not frozen. If this condition is found, the contractor will need to correct and/or replace the mixture. In the event the work zone crash cushion is damaged and needs to be replaced, it is considered incidental and replaced at no cost to the Commission.		'''Work Zone Crash Cushions (for Sec 612.4.2).''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of crash cushion the contractor is using. When inspecting the work zone crash cushion, make sure that the crash cushion is in the location as shown on the temporary traffic control plans and set up in accordance with the manufacturer’s recommendations. If the crash cushion is water-filled, MoDOT requires a mixture content per manufacturer’s recommendations so that the crash cushion will not freeze and create a safety hazard. During periods of extended cold weather, the crash cushion(s) should be checked periodically to make sure it has not frozen. If this condition is found, the contractor will need to correct and/or replace the mixture. In the event the work zone crash cushion is damaged and needs to be replaced, it is considered incidental and replaced at no cost to the Commission.

Kleins1: Corrected spelling errors

2022-03-17T16:49:55Z

Corrected spelling errors

← Older revision		Revision as of 11:49, 17 March 2022
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	\|align="center" colspan="2"\|Operations \|\| style="background:#BEBEBE" width="5"\| \|\|colspan="2" align="center" \|Operations		\|align="center" colspan="2"\|Operations \|\| style="background:#BEBEBE" width="5"\| \|\|colspan="2" align="center" \|Operations
	\|-		\|-
	\|width=100\|Follows directly behind truck ''(Ex: Will not track paint from striping operations)''\|\| Difficult to remove and install. ''(Ex: Truck ~~can not~~ be quickly used for other applications)'' \|\| style="background:#BEBEBE" width="5"\| \|\| Trailer TMA are usually easier to install and remove from the truck hitches.\|\|The driver may have difficulties backing, a spotter is recommended. ''(Ex: Backing up to pick up channelizers within a work zone and keeping the trailer out of the travel lane)''		\|width=100\|Follows directly behind truck ''(Ex: Will not track paint from striping operations)''\|\| Difficult to remove and install. ''(Ex: Truck cannot be quickly used for other applications)'' \|\| style="background:#BEBEBE" width="5"\| \|\| Trailer TMA are usually easier to install and remove from the truck hitches.\|\|The driver may have difficulties backing, a spotter is recommended. ''(Ex: Backing up to pick up channelizers within a work zone and keeping the trailer out of the travel lane)''
	\|-		\|-
	\|Easy Backing when spotter not available ''(Ex: During work zone removal)''\|\| Difficult to access plugs, wires and lighting connections during installation and removal \|\| style="background:#BEBEBE" width="5"\| \|\|After an impact, the trailer is removed from host vehicle and the truck is usually still serviceable. \|\|After an impact, the trailer needs towing by flat bed back to shop for repairs based on manufacturer recommendations		\|Easy Backing when spotter not available ''(Ex: During work zone removal)''\|\| Difficult to access plugs, wires and lighting connections during installation and removal \|\| style="background:#BEBEBE" width="5"\| \|\|After an impact, the trailer is removed from host vehicle and the truck is usually still serviceable. \|\|After an impact, the trailer needs towing by flat bed back to shop for repairs based on manufacturer recommendations
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	The term "protective vehicle" represents the use of the protective vehicle within operations. The term TMA represents a truck or trailer-mounted attenuator.		The term "protective vehicle" represents the use of the protective vehicle within operations. The term TMA represents a truck or trailer-mounted attenuator.

	The flashing arrow panel and warning lights shall not be active when the Protective Vehicle/TMA ~~istraveling~~ from the home domicile to the staging area/desired lane/work location. Once the Protective Vehicle/TMA has reached the staging area/desired lane/work location, the appropriate operating mode shall be displayed and turned on. If the Protective Vehicle/TMA leaves the staging area/desired lane/work location and travels to another staging area/desired lane/work location, the flashing arrow panel and warning lights shall not be active.		The flashing arrow panel and warning lights shall not be active when the Protective Vehicle/TMA is traveling from the home domicile to the staging area/desired lane/work location. Once the Protective Vehicle/TMA has reached the staging area/desired lane/work location, the appropriate operating mode shall be displayed and turned on. If the Protective Vehicle/TMA leaves the staging area/desired lane/work location and travels to another staging area/desired lane/work location, the flashing arrow panel and warning lights shall not be active.

	====612.1.3.1 TMA Typical Operations====		====612.1.3.1 TMA Typical Operations====

Smithk: updated broken link

2022-02-18T21:09:11Z

updated broken link

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	\|'''[http://sp/safety/csp/Pages/Safety-Videos.aspx Safety Videos]'''		\|'''[http://sp/safety/csp/Pages/Safety-Videos.aspx Safety Videos]'''
	\|-		\|-
	\|[http://~~wwwi~~/~~intranet~~/~~TMA2014~~.~~wmv~~ 2014 TMA Safety Points]		\|[http://sp/safety/csp/Pages/Safety-Videos.aspx 2014 TMA Safety Points]
	\|}		\|}

Smithk: updated broken link

2022-02-18T21:06:56Z

updated broken link

← Older revision		Revision as of 16:06, 18 February 2022
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	\|[[image:safety begins with me.jpg\|165px\|center]]		\|[[image:safety begins with me.jpg\|165px\|center]]
	\|-		\|-
	\|'''[http://~~wwwi~~/~~intranet~~/~~SafetyVideos~~.~~htm~~ Safety Videos]'''		\|'''[http://sp/safety/csp/Pages/Safety-Videos.aspx Safety Videos]'''
	\|-		\|-
	\|[http://wwwi/intranet/TMA2014.wmv 2014 TMA Safety Points]		\|[http://wwwi/intranet/TMA2014.wmv 2014 TMA Safety Points]

Smithk: Per EPS, revision supports the reclassification in the QPL; revision also provides guidance on when WZ crash cushions are to be used and when to reference the QPL for approved devices. Sand barrels do not fit in every project and WZ crash cushions are the alternative.

2021-11-17T16:58:39Z

Per EPS, revision supports the reclassification in the QPL; revision also provides guidance on when WZ crash cushions are to be used and when to reference the QPL for approved devices. Sand barrels do not fit in every project and WZ crash cushions are the alternative.

← Older revision		Revision as of 11:58, 17 November 2021
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	Sand barrels are most often used to shield fixed objects that cannot be removed or relocated. Sand barrels are recommended for temporary usage such as in work zones. A benefit/cost analysis is to be conducted before sand barrels are used in a permanent application.		Sand barrels are most often used to shield fixed objects that cannot be removed or relocated. Sand barrels are recommended for temporary usage such as in work zones. A benefit/cost analysis is to be conducted before sand barrels are used in a permanent application.

	An approved sand-filled impact attenuator may be installed on the exposed end of the barrier where the posted speed prior to construction on an existing facility or the anticipated posted speed of a temporary facility is greater than 35 mph. A crash cushion will be required on the upstream end for divided facilities, and on both ends for all two-way facilities. ~~Crash~~ cushions are discussed in [[617.1 Temporary Traffic Barriers#617.1.3.3 Crash Cushion\|EPG 617.1.3.3 Crash Cushion]]. Applicable pay items are included in the plans.		An approved sand-filled impact attenuator may be installed on the exposed end of the barrier where the posted speed prior to construction on an existing facility or the anticipated posted speed of a temporary facility is greater than 35 mph.
			<div id="A crash cushion will be required"></div>
	Crashworthy end terminals (Types A through E) should be used when sufficient width is not available for sand barrels. More information on proprietary crash cushions is available at EPG 617.1.3.3 Crash Cushion.		A crash cushion will be required on the upstream end for divided facilities, and on both ends for all two-way facilities. When space allows, sand barrel impact attenuators are the preferred choice for temporary protection. However, in the event that sand barrels cannot be used (for example, insufficient width), work zone crash cushions may be used instead. Work zone crash cushions provide a narrower option than sand barrels, but still perform the same function. Work zone crash cushions are discussed in [[617.1 Temporary Traffic Barriers#617.1.3.3 Crash Cushion\|EPG 617.1.3.3 Crash Cushion]]. Applicable pay items are included in the plans.

	==612.3 Construction Inspection Guidelines==		==612.3 Construction Inspection Guidelines==
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	<div id="Sand-Filled Impact Attenuator Array"></div>		<div id="Sand-Filled Impact Attenuator Array"></div>
	'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it hasn’t frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.		'''Sand-Filled Impact Attenuator Array (for Sec 612.4.2)''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of sand-filled impact attenuator the contractor is using. The use of more than one manufacturer’s sand barrels in an array is not allowed. When inspecting the sand-filled impact attenuator arrays, make sure that the array is in the location as shown in the temporary traffic control plans, and set up and filled in accordance with the manufacturer’s recommendations. All lids are to be on and secured. MoDOT requires rock salt intermixed with the sand so that any water that gets into the barrels will not freeze and create a safety hazard. When checking the contents of the barrels, rock salt should be visible in the sand mix. During periods of extended cold weather, the sand should be checked periodically to make sure it hasn’t frozen because the salt content has been exhausted. If this condition is found, the contractor will need to add more salt or replace the sand/salt mixture.
			<div id="Work Zone Crash Cushions"></div>
			'''Work Zone Crash Cushions (for Sec 612.4.3).''' The inspector is to request a copy of the manufacturer’s installation instructions for the particular brand of crash cushion the contractor is using. When inspecting the work zone crash cushion, make sure that the crash cushion is in the location as shown on the temporary traffic control plans and set up in accordance with the manufacturer’s recommendations. If the crash cushion is water-filled, MoDOT requires a mixture content per manufacturer’s recommendations so that the crash cushion will not freeze and create a safety hazard. During periods of extended cold weather, the crash cushion(s) should be checked periodically to make sure it has not frozen. If this condition is found, the contractor will need to correct and/or replace the mixture. In the event the work zone crash cushion is damaged and needs to be replaced, it is considered incidental and replaced at no cost to the Commission.