# DOT Training Solutions — Hazardous Materials Safety Interpretation

- **operation:** document
- **citation:** 22-0121
- **title:** DOT Training Solutions — Hazardous Materials Safety Interpretation
- **source type:** guidance
- **agency:** Pipeline and Hazardous Materials Safety Administration
- **status:** guidance
- **official:** true
- **published on:** 2023-02-02
- **effective on:** Not available
- **summary:** 22-0121 response to DOT Training Solutions concerning 178.345.
- **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-22-0121.json
- **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-22-0121.md
- **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-22-0121
- **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/docs/standards-rulemaking/hazmat/interpretations/77336/220121.pdf
**body:**

<<<PAGE 1>>>

U.S. Department
of Transportation
Pipeline and Hazardous
Materials Safety
Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
February 2, 2023
Arturo Prado
DOT Training Solutions
701 Briar Court
Brownsville, TX 78521
Reference No. 22-0121
Dear Mr. Prado:
This letter is in response to your November 4, 2022, email requesting clarification of the
Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the configuration
of bulk trailer valves. You ask whether a DOT 407 cargo tank motor vehicle (CTMV),
manufactured as a “wheels back” vehicle, as defined in 49 CFR § 393.5, fitted with a rear
loading valve located behind the fifth axle, and in full tow configuration is required to have an
internal self-closing stop valve with a sacrificial device.
According to § 178.345-8 and when solely considering accident damage protection, an internal
self-closing stop-valve with a sacrificial device is required only when seeking relief from
§ 178.345-8(b)(1). When a sacrificial device is required, it is subject to the strength and location
requirements found in § 178.345-8(b)(2). However, based on the photographs and information
you provided, we are unable to make the determination whether the configuration presented
meets the requirements of § 178.345-8(b)(1) or § 178.345-8(b)(2). Additionally, the CTMV is
still subject to the remaining requirements found in § 178.345-8, as well as any other applicable
requirements (i.e., tank outlet requirements found in § 178.345-11). These other requirements
must also be taken into consideration when making a final determination for valve requirements.
Please note, this Office does not make the determination whether specific individual
configurations meet the applicable requirements of the HMR.
I hope this information is helpful. Please contact us if we can be of further assistance.
Sincerely,
Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

<<<PAGE 2>>>

Baker
From: INFOCNTR (PHMSA)
To: Hazmat Interps
Subject: FW: Bulk trailer valve configuration 178.345-8
Date: Friday, November 4, 2022 3:56:07 PM
Attachments: image001.png
178.345-8 vs wheels back.pdf
22-0121
Hello Hazmat Interps,
See below and attached request for interpretation.
Thanks,
Jonathon, CTR
From: Arturo Prado <arturoprado@dottrainingsolutions.com>
Sent: Friday, November 4, 2022 2:22 PM
To: INFOCNTR (PHMSA) <INFOCNTR.INFOCNTR@dot.gov>
Subject: FW: Bulk trailer valve configuration 178.345-8
CAUTION: This email originated from outside of the Department of Transportation (DOT). Do
not click on links or open attachments unless you recognize the sender and know the content
is safe.
As requested here is my physical mailing address: 701 Briar Court, Brownsville, Texas 78521
Arturo Prado
Safety Consultant
Mobile: (913) 350-0371 or
(956) 455-6986/Toll Free: (866) 296-7394
Email: arturoprado@dottrainingsolutions.com
Website: https://dottrainingsolutions.com
From: Arturo Prado
Sent: Wednesday, October 26, 2022 2:14 PM
To: PHMSA.Pipelinesafety@dot.gov
Cc: James Dean <jdean@altomtransport.com>
Subject: Bulk trailer valve configuration 178.345-8

<<<PAGE 3>>>

393.86 Rear impact guards and rear end protection.
(a)(1) The requirements of paragraph (a) of this section do not apply to pole
trailers (as defined in §390.5 of this chapter); pulpwood trailers, low chassis
vehicles, special purpose vehicles, wheels back vehicles (as defined in §393.5);
and trailers towed in driveaway-towaway operations (as defined in § 390.5).
393.5 Definitions
Wheels back vehicle. (1) A trailer or semitrailer manufactured on or after January
26, 1998, whose rearmost axle is permanently fixed and is located such that the
rearmost surface of the tires (of the size recommended by the vehicle
manufacturer for the rear axle) is not more than 305 mm (12 inches) forward of
the transverse vertical plane tangent to the rear extremity of the vehicle.
178.345-8 Accident damage protection.
(b)(1) Any bottom damage protection device must be able to withstand a force of
155,000 pounds (based on the ultimate strength of the material) from the front,
side, or rear, uniformly distributed over each surface of the device, over an area
not to exceed 6 square feet, and a width not to exceed 6 feet. Suspension
components and structural mounting members may be used to provide all, or
part, of this protection. The device must extend no less than 6 inches beyond any
component that may contain lading in transit.
178.345-8 Accident damage protection

<<<PAGE 4>>>

Betts External Chemical Hydraulic Valve is classified as an external
self-closing stop valve and is widely used on DOT407 and 412 cargo tanks.
This is a robust and proven valve that satisfies the many requirements of
the chemical transportation industry. The 316-stainless body and
replaceable Teflon seal make this valve a versatile and reliable workhorse
for any fleet. This valve does NOT include a sacrificial shear section;
therefore, the cargo tank must have adequate accident damage
protection to shield the valve as specified in 49CFR §178.345-8.

<<<PAGE 5>>>

178.345-8 Accident damage protection.
(b)(1) Any bottom damage protection device must be
able to withstand a force of 155,000 pounds (based
on the ultimate strength of the material) from the
front, side, or rear, uniformly distributed over each
surface of the device, over an area not to exceed 6
square feet, and a width not to exceed 6 feet.
Suspension components and structural mounting
members may be used to provide all, or part, of this
protection. The device must extend no less than 6
inches beyond any component that may contain
lading in transit.

<<<PAGE 6>>>

393.5 Definitions
Wheels back vehicle. (1) A trailer or semitrailer manufactured
on or after January 26, 1998, whose rearmost axle is
permanently fixed and is located such that the rearmost
surface of the tires (of the size recommended by the vehicle
manufacturer for the rear axle) is not more than 305 mm (12
inches) forward of the transverse vertical plane tangent to the
rear extremity of the vehicle.
178.345-8 Accident damage protection.
(b)(1) Any bottom damage protection device must be able to
withstand a force of 155,000 pounds (based on the ultimate
strength of the material) from the front, side, or rear, uniformly
distributed over each surface of the device, over an area not to
exceed 6 square feet, and a width not to exceed 6 feet.
Suspension components and structural mounting members
may be used to provide all, or part, of this protection. The
device must extend no less than 6 inches beyond any
component that may contain lading in transit.

<<<PAGE 7>>>

Question does a DOT 407 cargo tank that was manufacture with wheels back configuration
(393.5) and fitted with rear loading valve required to have an internal valve with a sacrificial
device? If the valve is located aft of axle 5 when in full tow configuration, and section
178.345-8 states that the suspension components and structural mounting members may be
used to provide all, or part, of this protection. Does this configuration located close to the aft
axle relief carrier or manufacture from installing a internal valve with a sacrificial device.
Arturo Prado
Safety Consultant
Mobile: (913) 350-0371|Toll Free: (866) 296-7394
Email: arturoprado@dottrainingsolutions.com
Website: https://dottrainingsolutions.com
From: James Dean <jdean@altomtransport.com>
Sent: Wednesday, October 19, 2022 9:50 AM
To: Arturo Prado <arturoprado@dottrainingsolutions.com>
Subject: Bulk trailer valve configuration
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<<<PAGE 8>>>

HEEL
DID YOU CHECE
A DANGER
A DANGER
EMERGENCY
SHUTOFF
Steam outlet
LTOM
Transport, Inc.

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