Interpretation ID: 1985-01.45

TYPE: INTERPRETATION-NHTSA

DATE: 03/07/85

FROM: AUTHOR UNAVAILABLE; Jeffrey R. Miller; NHTSA

TO: Stephen T. Waimey, Esq; Dean Hansell, Esq., Donovan, Leisure, Newton and Irvine

TITLE: FMVSS INTERPRETATION

ATTACHMT: 8/30/79 letter from F. Berndt to Alfa Romeo

TEXT:

Stephen T. Waimey, Esq. Dean Hansell, Esq. Donovan Leisure Newton & Irvine 333 South Grand Avenue Los Angeles, California 90071

Dear Messrs. Waimey and Hansell:

I am responding to your correspondence regarding the definitions of "convertible" and "open body type vehicle" under National Highway Traffic Safety Administration (NHTSA) safety regulations.

Your first question concerns the definition of "open body type vehicle." Our regulations provide a definition at 49 CFR S571.3: "...a vehicle having no occupant compartment top or an occupant compartment top that can be installed or removed by the user at his convenience." The common usage of that term in our interpretations is that this term is intended to apply to multipurpose passenger vehicles, such as Jeep-type vehicles. Thus, neither of the automobiles in the pictures that you included with your letter (Porsche 911 Carrera Cabriolet and Porsche 911 Carrera Targa) are considered to be open-body vehicles.

You also ask whether the Porsche 911 Targa is considered a convertible. You state that there is no fixed, rigid structural member joining the "A" pillar with the "B" pillar. Despite this absence, the Targa roof, beginning behind the "B" pillar, apparently is a fixed, rigid structural member that meets Federal roof-crush standards.

You are correct in stating that our regulations do not expressly define "convertible." NHTSA interpretations, however, have consistently defined "convertible" as a vehicle whose "A" pillar or windshield peripheral support is not joined with the "B" pillar (or rear roof support rearward of the "B" pillar position) by a fixed, rigid structural member. Thus, the Porsche 911 Targa is considered a convertible because it meets this definition. While the vehicle is therefore not required to meet the roof-crush standards, it is commendable that Porsche has designed it to do so.

If you have any further questions, please let me know.

Sincerely,

Jeffrey R. Miller Chief Counsel

January 4, 1985

Frank Berndt, Esq. Chief Counsel National Highway Traffic Safety Administration 400 7th Street S.W. Washington, D.C. 20590

Dear Mr. Berndt:

We represent Dr. Ing. h.c.F. Porsche AG ("Porsche") and on behalf of Porsche we seek your comments about apparent ambiguities in the regulations. These regulations are relevant to certain research and development work being done by Porsche.

Specifically, the definition of "open-body type vehicle" and the usage of that phrase and of the undefined term "convertible" in the Federal Motor Vehicle Safety Standards are unclear. This leaves open questions as to (1) whether the Porsche 911 Cabriolet and the Porsche 911 Targa are "open body-type vehicles" and (2) whether the Porsche 911 Targa is a "convertible." (Pictures of both vehicles are attached to this letter). The following is our understanding of the applicable law and identifies the ambiguities as we see them.

(1) Open-body Type Vehicle. Section 571.3 of the NHTSA regulations, 49 C.F.R. S 571.3, defines an "open-body type vehicle" as "a vehicle having no occupant compartment top or an occupant compartment top that can be installed or removed by the user at his convenience." One interpretation of this definition is that the concept of a "removable" top includes a convertible top that can be folded down. However, the use of the term in NHTSA regulations suggests that the term is limited to vehicles that are usually manufactured with no doors and/or windshield or removable doors and/or windshield, such as four-wheel drive utility vehicles, and other specialty vehicles, and is this not intended to include convertible passenger cars such as the Porsche Cabriolet.

For example, in at least 3 cases, open-body type vehicles are treated separately from convertibles. Section 571.114 of the regulations exempts from the requirements of paragraph S4.5 of Safety Standard Number 114 (theft protection) only "open-body type vehicles that are manufactured for operation without doors and that either have no doors or have doors that are designed to be easily attached to and removed from the vehicle by the vehicles owner." Section 571.212 exempts "open body type vehicles with fold-down or removable windshields" from Safety Standard Number 212 (windshield mounting). Section 571.219 exempts "open-body type vehicles with "fold down" or removable windshields" from Safety Standard Number 219 (windshield zone intrusion). Conversely, Section 571.208 of the regulations exempts both "convertibles and open-body vehicles" from the requirements of paragraph S4.1.1.3.1 of Safety Standard Number 208 (occupant crash protection).* Similarly, the test conditions set forth in Section 571.208 provide (at paragraph S8.1.6) that for the frontal, lateral and roll-over tests "convertibles and open-body type vehicles have the top, if any, in place in the closed passenger compartment configuration." Finally, Section 571.205, as recently amended (at paragraph S5.1.2.4), prohibits glass and plastic glazing materials from being used in "convertibles, in vehicles that have no roof or in vehicles whose roofs are completely removable.***

Similarly, NHTSA Federal Register notices suggest that an open-body type vehicle is different than a convertible. In granting Anden Holdings Ltd. a temporary exemption from Safety Standard Numbers 104 and 201

* Section 571.208 provides (at paragraphs S4.1.1.3.2 and S4.1.2.3.2) that "convertibles and open-body type vehicles shall utilize either a Type l or a Type 2 seatbelt assembly.

** This second half of this reference appears to be a paraphrase of the definition of "open-body type vehicle."

(windshield wiping and washing systems and occupant protection in interior impact), because it is an open-body type vehicle, acting NHTSA Administrator Steed stated "the Auburn replica, as is true of many open-body vehicles, has no header and the windshield frame is too narrow to support a sun visor mounting." See 47 Fed. Reg. 34, 071 (1982). Further, discussion appears at both 46 Fed. Reg. 32,251 (1981) and 45 Fed. Reg. 85,450 (1980) about whether to exempt open-body type vehicles with readily removable or no doors from the key-in-ignition warning requirements of safety Standard Number 114 (theft protection).

Finally, use of the term "convertible" in Sections 571.210, 571.216, and 571.302 of the Regulations without the term "open-body type vehicle" suggests that a convertible is not an open-body type vehicle.

In view of the context in which the term "open-body type vehicles" has been used in NHTSA regulations, it thus appears that neither the Porshce 911 convertible nor the Porsche 911 Targa are intended to be considered "open-body type vehicles." It may be that this result is achieved because a convertible top is not completely removable (i.e., it is only folded down) and the Targa top actually leaves most of the roof in place (in the same way that a "T-top" roof does). however, because this matter is not clear, Porsche would appreciate your comments on the regulatory intent of these terms.

(2) The Porsche 911 Targa as a Convertible. You wrote a letter on August 30, 1979, to Alfa Romeo concluding that the term "convertible" is not defined in NHTSA regulations though it is apparently described or defined elsewhere. (For your convenience I attach a copy of the August 30, 1979 letter). The letter concludes:

"While our regulations do not include a formal definition of "convertible," the agency has stated that it considers a convertible to be a vehicle whose "A" pillar or windshield peripheral support is not joined with the "B" pillar (or rearward support rearward of the "B" pillar position) or by a fixed, rigid structural member."

In our research, we could not locate the source for that definition.

Also, as far as we could determine, the regulations still do not define the term "convertible." The term is, however, used four times in Section 571.208 (at paragraphs S4.1.1.3.1, S4.1.1.3.2, S4.1.2.3.2. and S8.1.6), and once each in Section 571.108 (paragraph S4.3. 1.8), in Section 571.205 (paragraph S5.1.2.4), in Section 571.216 (paragraph S3), and in Section 571.302 (paragraph S4.1). In each instance, no information about the meaning of "convertible" is given. Since the Porsche 911 Targa's "A" pillar is not joined with its "B" pillar, it thus appears that it might meet the definition of a "convertible." On the other hand, since the Targa roof (which begins at the B pillar position and continues by means of the rear glass window to the rear body deck) is a fixed, rigid structural member that provides the Targa with a roof from that point to the rear (which roof meets regulatory roof-crush standards), where the entire roof is non-structural, thus does not necessarily apply.*

* We note that there may be another undefined class of vehicles evolving, a class consisting of partially covered vehicles such as the "T"-top, cars with sun roofs and the Targa. Perhaps our focus in distinguishing between only convertibles, open-top vehicles and coupes is too narrow. For example, Section 571.205 (at paragraph S5.1.2.4) provides that glass-plastic glazing materials may not be used in convertibles. This prohibition does not apply to vehicles with sun roofs or "T"-tops, 48 Fed. Reg. 52,062 (1983), because "the probability that the plastic side of the glazing in those vehicles would be directly exposed to the sun over a prolonged period is particularly small due to the installation angle of the windshield and restricted path of the sunlight through the opening in the top of the vehicle." Id. However, because of the presence in the Targa of a fixed structural roof from the B-pillar areas rearwards, the plastic side of the glazing would not be directly exposed to the sun. Thus, in at least in this area, the Targa might more reasonably be considered as a member of a "T"-top/Targa class of vehicles.

Thank you for your courtesy and assistance.

Yours truly,

Stephen T. Waimey

Dean Hansell Enc: August 30, 1979 letter from NHTSA to Alfa Romeo. Omitted Here