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DMU Compliance with FRA Regs

Compliance with FRA Regulations

The FRA has very stringent requirements for passenger and commuter vehicles, the majority of which can be found in the Code of Federal Regulations (CFR). This massive, multi-volume text covers all aspects of our governance, from roads to rails and everything in between, in detail so fine that a complete set of Encyclopedia Britannica pales in comparison.

Railroading in detail is covered in section 49, so you will see reference to specific parts of the CFR in this explanation beginning with 49CFR. That’s why. Structural regulations governing passenger cars are contained mostly in 49CFR Part 238 — Passenger Equipment Safety Standards. What makes Colorado Railcar’s DMU so special is that it is the first DMU to comply with all of these standards.

DMUs - or Diesel Multiple Unit cars – have gained tremendous popularity in Europe, where they have proven their worth in passenger service on more lightly used intercity routes that wouldn’t be economical to operate using more conventional locomotive hauled trains. As the need for short-haul passenger transport becomes more apparent in the United States, those advantages have begun to apply as well. (To read more about the advantages, click here.) While modern and attractive looking, the DMUs that are so popular in Europe cannot run in the United States due to the stringent requirements set forth in the CFR.

A typical European DMU is exmeplified in this shot of German National Railways' Bombardier Talent DMU 643 at the Main Station in Saarbrücken, Germany. Photo by Mario López Gómez. August 3, 2004.

The CFR is written in a language very much like English, but not entirely similar. I think the actual dialect is Lawyerese, but I could be wrong. (They don’t call it “code” for nothing…) At any rate, an excursion into the CFR is best attempted with at least a tall glass of water nearby — this is some pretty dry reading, and not something that is accomplished quickly.

Colorado Railcar’s main selling point with the DMU is that it is fully FRA compliant. But what exactly does that mean? 49CFR Part 238 consists of about 80 pages of small text, covering everything from definitions to specific structural requirements to requirement for materials used to inspection and maintenance to fines and penalties. It was my hope to decipher the CFR and give some highlights of the reasons why the DMU is so special. Throughout this description, I will reference and quote the CFR frequently.

What lies beneath the skin of the DMU prototype. Photo courtesy of Colorado Railcar.

The importance of following the guidelines in the CFR is found very early on in Part 238, Subpart A, rule 238.1b, which states in part that the part prescribes minimum Federal safety standards for railroad passenger equipment. What that means exactly is revealed in the definitions, (rule 238.5), which defines passenger equipment as:

(1) All powered and unpowered passenger cars, locomotives used to haul a passenger car, and any other rail rolling equipment used in a train with one or more passenger cars. Passenger equipment includes —

(i) A passenger coach,
(ii) A cab car,
(iii) A MU locomotive.
(iv) A locomotive not intended to provide transportation for a member of the public that is used to power a passenger train, and
(v) Any non-self-propelled vehicle used in a passenger train, including an express car, baggage car, mail car, freight car, or a private car.

The DMU fits clearly into this category, as does virtually everything else that could be operated in a commuter environment on standard tracks. Exemptions are made for operations like light rail where there is no freight traffic, compatible passenger equipment is used, and speeds don’t exceed 79mph.

The industry reserves the term ‘heavy rail’ for locomotive-hauled trains, as well as self-propelled cars like the DMU and much older RDC, or rail diesel car. Heavy rail requirements are spelled out in part 238.

Subpart B, rules 238.101 to 238.119 deal with things like fire safety, emergency exits and protection against personal injury. The meat of what makes the DMU special can be found in Subpart C — Specific Requirements for Tier I Passenger Equipment. (Tier I passenger equipment is equipment that operates at speeds not exceeding 125 mph.)

“Rule 238.203 — Static end strength (a)(1)” is the most frequently referenced rule in regards to the DMU’s crashworthiness, thanks to the compression test that must be performed on each and every DMU before it is put into service. That rule reads:

Except as further specified in this paragraph or in paragraph (d), on or after November 8, 1999 all passenger equipment shall resist a minimum static end load of 800,000 pounds applied on the line of draft (meaning the frame inline with the couplers - ed.) without permanent deformation of the body structure.

In addition to the compression load requirements of the above rule, the ends and bodies of cars must also meet the requirements of several other rules, including rule 238.211 — Collision Posts, which covers the impact resistance of structures above the frame line. Part 238 defines collision posts as structural members of the end structures of a vehicle that extend vertically from the underframe to which they are securely attached and that provide protection to occupied compartments from an object penetrating the vehicle during a collision. Put simply, if a passenger car hits something head-on, the collision posts are intended to keep whatever is hit from crushing its way into the passenger area.

Rule 238.211 requires two collision posts, located at approximately the one-third points laterally, each with a shear strength of not less than 300,000 pounds, or an equivalent end structure that can withstand the sum of forces that each collision post… is required to withstand.

Also, rule 238.205 requires either an anti-climbing mechanism capable of resisting an upward or downward vertical force of 100,000 pounds without failure, or AAR Type H or Type F couplers at both ends. As prescribed in rule 238.207, passenger equipment must have coupler carriers that withstand the same forces, and equipment connected by an articulated joint is also required to comply with this requirement and rule 238.205.

Confused yet? Well, grab another glass of water, because it’s time to explore things like corner posts, side structure and rollover strength.

Corner posts are similar to collision posts, except that they are in the corners, or the intersection of the front or rear surface with the side surface of a rail vehicle. The definition also states that corner posts may be combined with the collision posts to become part of the end structure. Rule 238.213(a) covers the collision posts, and states:

Each passenger car shall have at each end of the car, placed ahead of the occupied volume (the place where the passengers and crew are - ed.) two full height corner posts capable of resisting:
(1) A horizontal load of 150,000 pounds at the point of attachment to the underframe without failure;
(2) A horizontal load of 20,000 pounds at the point of attachment to the roof structure without failure; and
(3) A horizontal load of 30,000 pounds applied 18 inches above the top of the floor without permanent deformation.

The above photo of the DMU’s superstructure shows how the car complies with the side structure requirements set forth in rule 238.217 through what in the text is defined as a truss construction. In addition to a bunch of engineering data that I won’t bore you with, it also spells out a requirement for steel side sheathing of not less than 1/8 thickness, or 40 percent less when the sheathing is used on a truss construction and serves no load-carrying function.

Rollover strength is an important rule, and is set forth in rule 238.215. This text is actually pretty clear, so I will let it speak for itself:

(a) Each passenger car shall be designed to rest on its side and be uniformly supported at the top (“roof rail”), the bottom cords (“side sill”) of the side frame, and, if bi-level, the intermediate floor rail.

After some specific requirements regarding stress yields, it goes on to state in part:

(b) Each passenger car shall also be designed to rest on its roof so that any damage in occupied areas is limited to the roof sheathing and framing.

There’s plenty more where that came from, like rules regarding windows (238.211), electrical systems (238.255), suspension (238.227), braking systems (238.231) and much much more. There are even rules governing how seats are to be mounted (238.233(a)) and how many G-forces crew cab seats, overhead storage racks and other interior fittings are required to withstand (8g longitudinal, 4g vertical, and 4g lateral, according to rule 238.233 (b-c and f))

According to the APTA Voluntary Standards and Recommended Practices, the American Public Transportation Association (APTA) has even more strict requirements than the federal minimum, including 300,000 pound corner post strength, 500,000 pound collision post strength, and 200,000 pound anti-climber strength. Colorado Railcar’s DMU meets these requirements as well.

In comparison, the Bombardier Talent, Siemens Regio-Sprinter, and other similar European DMUs (classed as light DMUs by the industry) fall far short of the requirements. For instance (according to a report prepared for the Sonoma-Marin Area Rapid Transit, click here for the 2Mb PDF file) the light DMUs average around 400,000 pounds static end load, or about half the FRA requirement. Light rail vehicles in use in many urban settings are about 200,000 pounds loading.

So what does this all mean? Why even worry about compliance when it is possible to secure waivers (see rule 238.7) that make it possible to run virtually any equipment under certain circumstances? The answer lies in the fact that in many cases, the requirements for exemption are very restrictive.

Again citing the SMART report, the FRA is likely to require separation of light and heavy vehicles either by time (meaning day vs. night for instance) or space (meaning light vehicles may only operate in an area that no heavy vehicles will, and vice-versa.) The majority of the passenger rail projects in operation or proposed operate in conjunction with freight traffic on rails owned by a party besides the transit agency. The disruption to normal services required to meet the requirements would in many cases make it impossible for the railroad and transit agency both to operate successfully.

FRA Compliance is only one of the ways that Colorado Railcar has sought to make the DMU the best choice for the transit market. You can read more by checking out the DMU Advantages page, or get more information about the single level DMU, double decker DMU and commuter coaches by following those links.

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