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179

Part 179: SPECIFICATIONS FOR TANK CARS

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https://www.phmsa.dot.gov/about-phmsa/phmsa-faqs.

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This section of the website provides the ability to find regulations information including regulations parts, content of sections, and interpretations for regulations sections. Below is a list of parts, identified by the part number and subject. To browse sections by part, click on the subject link below. You will be taken to the eCFR website to view sections for a part.

A written regulatory interpretation, response to a question, or an opinion concerning a pipeline safety issue may be obtained by submitting a written request to the Office of Pipeline Safety (PHP–30), PHMSA, U.S. Department of Transportation, 1200 New Jersey Avenue SE., Washington, DC 20590–0001 or at the email address: pipeline_interp_submittal@dot.gov. In addition to email address, the requestor must include his or her return address and should also include a daytime telephone number. Requests should be submitted at least 120 days before the time the requestor needs a response.

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View part 179 on the ECFR website

Regulation Sections

Section Subject
179.1 General
179.2 Definitions and abbreviations
179.3 Procedure for securing approval
179.4 Changes in specifications for tank cars
179.5 Certificate of construction
179.6 Repairs and alterations
179.7 Quality assurance program
179.8 Limitation on actions by states, local governments, and Indian tribes
179.10 Tank mounting
179.11 Welding certification
179.12 Interior heater systems
179.13 Tank car capacity and gross weight limitation
179.14 Coupler vertical restraint system
179.15 Pressure relief devices
179.16 Tank-head puncture-resistance systems
179.18 Thermal protection systems
179.20 Service equipment; protection systems
179.22 Marking
179.24 Stamping
179.100 General specifications applicable to pressure tank car tanks
179.100-1 Tanks built under these specifications shall comply with the requirements of 179.100, 179.101 and
when applicable, 179.102 and 179.103
179.100-3 Type
179.100-4 Insulation
179.100-6 Thickness of plates
179.100-7 Materials
179.100-8 Tank heads
179.100-9 Welding
179.100-10 Postweld heat treatment
179.100-12 Manway nozzle, cover and protective housing
179.100-13 Venting, loading and unloading valves, measuring and sampling devices
179.100-14 Bottom outlets
179.100-16 Attachments
179.100-17 Closures for openings
179.100-18 Tests of tanks
179.100-19 Tests of safety relief valves
179.100-20 Stamping
179.101 Individual specification requirements applicable to pressure tank car tanks
179.101-1 Individual specification requirements
179.102 Special commodity requirements for pressure tank car tanks
179.102-1 Carbon dioxide, refrigerated liquid
179.102-2 Chlorine
179.102-3 Materials poisonous by inhalation
179.102-4 Vinyl fluoride, stabilized
179.102-17 Hydrogen chloride, refrigerated liquid
179.103 Special requirements for class 114A * * * tank car tanks
179.103-1 Type
179.103-2 Manway cover
179.103-3 Venting, loading and unloading valves, measuring and sampling devices
179.103-4 Safety relief devices and pressure regulators
179.103-5 Bottom outlets
179.200 General specifications applicable to non-pressure tank car tanks (Class DOT-111, DOT-117
179.200-1 Tank built under these specifications must meet the applicable requirements in this part
179.200-3 Type
179.200-4 Insulation
179.200-6 Thickness of plates
179.200-7 Materials
179.200-8 Tank heads
179.200-9 Compartment tanks
179.200-10 Welding
179.200-11 Postweld heat treatment
179.200-13 Manway ring or flange, pressure relief device flange, bottom outlet nozzle flange, bottom washout nozzle flange and other attachments and openings
179.200-14 Expansion capacity
179.200-15 Closures for manways
179.200-16 Gauging devices, top loading and unloading devices, venting and air inlet devices
179.200-17 Bottom outlets
179.200-19 Reinforcements, when used, and appurtenances not otherwise specified
179.200-21 Closures for openings
179.200-22 Test of tanks
179.200-23 Tests of pressure relief valves
179.200-24 Stamping
179.201 Individual specification requirements applicable to non-pressure tank car tanks
179.201-1 Individual specification requirements
179.201-3 Lined tanks
179.201-4 Material
179.201-5 Postweld heat treatment and corrosion resistance
179.201-6 Manways and manway closures
179.201-8 Sampling device and thermometer well
179.201-9 Gauging device
179.201-10 Water capacity marking
179.201-11 Insulation
179.202 Individual specification requirements applicable to DOT-117 tank car tanks
179.202-1 Applicability
179.202-3 Approval to operate at 286,000 gross rail load (GRL)
179.202-4 Thickness of plates
179.202-5 Tank head puncture resistance system
179.202-6 Thermal protection system
179.202-7 Jackets
179.202-8 Bottom outlets
179.202-9 Top fittings protection
179.202-10 ECP brakes
179.202-11 Individual specification requirements
179.202-12 Performance standard requirements (DOT-117P)
179.202-13 Retrofit standard requirements (DOT-117R)
179.220 General specifications applicable to nonpressure tank car tanks consisting of an inner container supported within an outer shell (class DOT-115)
179.220-1 Tanks built under these specifications must meet the requirements of 179.220 and 179.221
179.220-3 Type
179.220-4 Insulation
179.220-6 Thickness of plates
179.220-7 Materials
179.220-8 Tank heads
179.220-9 Compartment tanks
179.220-10 Welding
179.220-11 Postweld heat treatment
179.220-13 Inner container manway nozzle and cover
179.220-14 Openings in the tanks
179.220-15 Support system for inner container
179.220-16 Expansion capacity
179.220-17 Gauging devices, top loading and unloading devices, venting and air inlet devices
179.220-18 Bottom outlets
179.220-20 Reinforcements, when used, and appurtenances not otherwise specified
179.220-22 Closure for openings
179.220-23 Test of tanks
179.220-24 Tests of pressure relief valves
179.220-25 Stamping
179.220-26 Stenciling
179.221 Individual specification requirements applicable to tank car tanks consisting of an inner container supported within an outer shell
179.221-1 Individual specification requirements
179.300 General specifications applicable to multi-unit tank car tanks designed to be removed from car structure for filling and emptying (Classes DOT-106A and 110AW).
179.300-1 Tanks built under these specifications shall meet the requirements of 179.300 and 179.301
179.300-3 Type and general requirements
179.300-4 Insulation
179.300-6 Thickness of plates
179.300-7 Materials
179.300-8 Tank heads
179.300-9 Welding
179.300-10 Postweld heat treatment
179.300-12 Protection of fittings
179.300-13 Venting, loading and unloading valves
179.300-14 Attachments not otherwise specified
179.300-15 Pressure relief devices
179.300-16 Tests of tanks
179.300-17 Tests of pressure relief devices
179.300-18 Stamping
179.300-19 Inspection
179.300-20 Reports
179.301 Individual specification requirements for multi-unit tank car tanks
179.400 General specification applicable to cryogenic liquid tank car tanks
179.400-1 General
179.400-3 Type
179.400-4 Insulation system and performance standard
179.400-5 Materials
179.400-6 Bursting and buckling pressure
179.400-7 Tank heads
179.400-8 Thickness of plates
179.400-9 Stiffening rings
179.400-10 Sump or siphon bowl
179.400-11 Welding
179.400-12 Postweld heat treatment
179.400-13 Support system for inner tank
179.400-14 Cleaning of inner tank
179.400-15 Radioscopy
179.400-16 Access to inner tank
179.400-17 Inner tank piping
179.400-18 Test of inner tank
179.400-19 Valves and gages
179.400-20 Pressure relief devices
179.400-21 Test of pressure relief valves
179.400-22 Protective housings
179.400-23 Operating instructions
179.400-24 Stamping
179.400-25 Stenciling
179.401 Individual specification requirements applicable to inner tanks for cryogenic liquid tank car tanks
179.401-1 Individual specification requirements
179.500 Specification DOT-107A * * * * seamless steel tank car tanks
179.500-1 Tanks built under these specifications shall meet the requirements of 179.500
179.500-3 Type and general requirements
179.500-4 Thickness of wall
179.500-5 Material
179.500-6 Heat treatment
179.500-7 Physical tests
179.500-8 Openings in tanks
179.500-10 Protective housing
179.500-11 Loading and unloading valves
179.500-12 Pressure relief devices
179.500-13 Fixtures
179.500-14 Test of tanks
179.500-15 Handling of tanks failing in tests
179.500-16 Tests of pressure relief devices
179.500-17 Marking
179.500-18 Inspection and reports