ID: nht79-4.39

DATE: 08/03/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Ontario Bus Industries Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your July 16, 1979, letter asking two questions about the test procedures of Standard No. 217, Bus Window Retention, as they apply to buses you manufacture.

First, you ask whether side service doors can be counted in determining the proper amount of bus emergency exits as required by the standard. As long as side service doors comply with all requirements applicable to emergency doors, they can be considered emergency exits for purposes of compliance with the standard.

Your second question asks whether glazing in a door is tested for window retention, and if so, whether it is tested while the door is installed in a bus. The answer to both parts of this question is yes. All bus glazing, that is of the minimum size specified in the standard, must comply with the window retention requirement. The intent of the window retention requirement is to prevent openings in buses that might result in the ejection of occupants from the vehicle during an accident. In order for this requirement to have meaning, the glazing must be tested as it is installed in the vehicle to ensure the integrity of both the glazing and its surrounding structure. This means that glazing in vehicle doors is tested while the door is in the normal closed condition. If the door opens during the test, the vehicle would not be in compliance with the requirements.

SINCERELY,

Ontario Bus Industries Inc.

JULY 16, 1979

Office of Chief Counsel, NHTSA

Dear Sir,

This company was the designer and manufacturer of the Orion Mid size Transit bus.

More recently the deliveries to the U.S. market have been taken over by Transportation Manufacturing Corporation of Roswell, New Mexico, who manufacture and market the buses in the U.S.A. under the "Citycruiser" trade name.

A query has arisen concerning the application of MVSS 217 to this model bus on a point that was raised before the introduction of the model and for which a verbal answer was given when the prototype was presented in Washington on October 5th 1977.

The point at issue was to what extent and under what Criteria the service doors can be considered as "unobstructed openings for emergency exit" as required in S 5.2 (provision of emergency exits) and more particularly the "side exits" as required in S 5.2.1 (Buses with GVWR of more than 10,000 pounds).

It was verbally confirmed at the time that service doors could be regarded as side exits for emergency exit, provided they met the requirements of S 5.3 (Emergency exit release), S 5.4 (Emergency exit extension) and S 5.5 (Emergency exit identification). Official confirmation of the above is hereby requested.

Finally, a clear ruling was not given on the application of S 5.1 Window retention when applied to the glazing in service doors. It is reasonably clear that the glass in the door frame should meet the requirements. It is less obvious that the door in its frame, when used as a service door, must meet this requirement, ie. the glass be tested in the door, the door being in the bus.

If not, does this requirement become mandatory, when the service door is designated as a side exit?

The doors are presently being constructed so as to meet this requirement, but a ruling on this point is hereby requested.

CC: E. CUMMINGS -- TRANSPORTATION MFG. CO.

ID: aiam0799

Dear Mr. Eckhold:This is in reply to your letter of July 26, 1972 concerning the adjustment of a tractor's fifth wheel under the test conditions proposed in Docket 70-17, Notice 5.; You state that it is not possible to load the tractor to its GVWR wit the tractor's nonsteerable axles and the trailer's axles at GAWR if the fifth wheel is set in more than one position. If this is the case, and the correct loading can be obtained with the fifth wheel in one position only, then only that position will be used in compliance testing. If more than one position can be used to produce the correct loading, the tractor must conform to the requirements of the standard with the fifth wheel at any such position.; Sincerely, Richard B. Dyson, Assistant Chief Counsel

ID: nht88-2.61

TYPE: INTERPRETATION-NHTSA

DATE: 06/30/88

FROM: ERIKA Z. JONES -- NHTSA CHIEF COUNSEL

TO: TERRY K. BROCK -- NATIONAL SALES MANAGER COONS MANUFACTURING INC.

TITLE: NONE

ATTACHMT: LETTER DATED 09/09/87 FROM TERRY K BROCK TO STEVE KRATZKE RE CLARIFICATION OF FMVSS CODE 217; OCC 1009; LETTER DATED 08/20/87 FROM TERRY K BROCK TO SABASTIAN MESSINA; LETTER DATED 08/28/87 FROM ST MESSINA TO TERRY K BROCK RE COONS MANUFACTURING INC DIAMOND VIP BUS 25 PASSENGERS MC 157-87

TEXT: Dear Mr. Brock:

This is a response to your letter of last year seeking an interpretation of Standard 217, Bus Window Retention and Release (49 CFR @ 571.217). I apologize for the delay in this response. Specifically, you asked whether the front entrance door of a bus may be considered as an emergency exit under Standard 217. You stated that some of your company's buses have the front entrance door labeled as an emergency exit, and equipped with the emergency release mechanism required by Standard 217. You enclosed an August 28, 1987 letter from the New Jersey Department of Transportation referencing Federal Motor Carrier Safety Regulations that "require . . . emergency exits (to) comply with" Standard 217. The letter from New Jersey states that a "front entrance d oor cannot be considered (as an emergency exit) since the intent of the regulations is to provide emergency escape through push out windows and roof escape hatches."

You asked whether we interpret Standard 217 as precluding front entrance doors from also serving as emergency exits. The answer to your question is no. As long as the front door meets all applicable requirements for emergency exits under Standard 217, the door can be considered as an emergency exit. Contrary to the opinion stated in the New Jersey letter, it never has been this agency's position that only push-out window and roof exits may be used to satisfy Standard 217 requirements. (See 37 FR 939 4, 9395, May 10, 1972; copy enclosed.)

The question of whether a front entrance door may be a required emergency exit under Standard 217 depends upon (1) the vehicle's gross vehicle weight rating (GVWR); and (2) whether the vehicle is a school bus, or a bus other than a school bus. I will ad dress each of the possibilities separately.

Bus Other Than a School Bus, and With a GVWR of More Than 10,000 Lbs.

A front entrance door can serve as a required emergency exit under Standard 217 in a bus that is not a school bus, and that has a GVWR of more than 10,000 pounds. For such buses, paragraphs S5.2.1 and S5.2.1.1 of Standard 217 generally require the bus t o have "side exits and at least one rear exit," or "one side door for each three passenger seating positions." If the bus configuration precludes installing an accessible rear exit, then a manufacturer may install a roof exit under the conditions set out in S5.2.1.

Bus Other Than a School Bus, and With a GVWR of 10,000 Lbs. or Less

A front entrance door can also serve as a required emergency exit for buses other than school buses with a GVWR of 10,000 pounds or less. For these buses, the vehicle must have windows or other emergency exits that meet the requirements set out in parag raphs S5.2.2, or S5.3 through 5.5 of the Standard. If the vehicle's emergency exits are standard, roll-down windows, or the vehicle's entrance and exit doors, then these exits must meet the specifications of S5.2.2(b). Under that provision, the windows and doors must be manually operable, and must open to a position that provides a specified area for getting out. Note that under S5.5.1, these exits do not have to meet Standard 217 marking requirements. The agency has determined that people who are ol d enough to read instructions generally are familiar with the operation of standard, roll-down windows and doors, and that there is little justification for requiring emergency exit markings for these exits. (40 FR 17266, April 18, 1975.)

If the vehicle's emergency exits are push-out windows or some other emergency exit, then the vehicle must comply with paragraphs S5.3 through S5.5. A manufacturer must label these exits under S5.5 because they are specially-installed emergency exits who se means of operation may not be obvious to the passengers.

School Buses

A front entrance door can not serve as a required emergency exit in a school bus, regardless of the vehicle's weight. Paragraph S5.2.3 of Standard 217 requires all school buses to have either (1) one rear emergency door, or (2) "one emergency door on th e vehicle's left side that is in the rear half of the bus passenger compartment and is hinged on its forward side, and one push-out window." A manufacturer who chooses to meet school bus emergency exit requirements under the second option could not use t he front entrance door as a required emergency exit under Standard 217, since that door would not be in the rear half of the passenger compartment. However, if a manufacturer chose to install an "additional" emergency exit such as a front entrance door, NHTSA regulations would not prohibit installing this exit. As the agency long has held, any "extra" emergency exit installed in a school bus must comply with Standard 217 provisions applicable to emergency exits in buses other than school buses.

Please understand that this letter addresses only Standard 217, and does not address or interpret any Federal Motor Carrier regulations. If you have any questions about those regulations, you should contact the Federal Highway Administration.

I hope you find this information helpful. If you have further questions, please contact Joan F. Tilghman of my staff, at (202) 366-2992.

ENCLOSURE

ID: 2867o

Terry K. Brock, National Sales Manager
Coons Manufacturing Inc.
2300 West Fourth Street/Box 489
Oswego, KS 67356

Dear Mr. Brock:

This is a response to your letter of last year seeking an interpretation of Standard 217, Bus Window Retention and Release (49 CFR 571.217). I apologize for the delay in this response. Specifically, you asked whether the front entrance door of a bus may be considered as an emergency exit under Standard 217. You stated that some of your company's buses have the front entrance door labeled as an emergency exit, and equipped with the emergency release mechanism required by Standard 217. You enclosed an August 28, 1987 letter from the New Jersey Department of Transportation referencing Federal Motor Carrier Safety Regulations that "require...emergency exits (to) comply with" Standard 217. The letter from New Jersey states that a "front entrance door cannot be considered (as an emergency exit) since the intent of the regulations is to provide emergency escape through push out windows and roof escape hatches."

You asked whether we interpret Standard 217 as precluding front entrance doors from also serving as emergency exits. The answer to your question is no. As long as the front door meets all applicable requirements for emergency exits under Standard 217, the door can be considered as an emergency exit. Contrary to the opinion stated in the New Jersey letter, it never has been this agency's position that only push-out window and roof exits may be used to satisfy Standard 217 requirements. (See 37 FR 9394, 9395, May 10, 1972; copy enclosed.)

The question of whether a front entrance door may be a required emergency exit under Standard 217 depends upon (1) the vehicle's gross vehicle weight rating (GVWR); and (2) whether the vehicle is a school bus, or a bus other than a school bus. I will address each of the possibilities separately.

Bus Other Than a School Bus, and With a GVWR of More Than 10,000 Lbs.

A front entrance door can serve as a required emergency exit under Standard 217 in a bus that is not a school bus, and that has a GVWR of more than 10,000 pounds. For such buses, paragraphs S5.2.1 and S5.2.1.1 of Standard 217 generally require the bus to have "side exits and at least one rear exit," or "one side door for each three passenger seating positions." If the bus configuration precludes installing an accessible rear exit, then a manufacturer may install a roof exit under the conditions set out in S5.2.1.

Bus Other Than a School Bus, and With a GVWR of 10,000 Lbs. or Less

A front entrance door can also serve as a required emergency exit for buses other than school buses with a GVWR of 10,000 pounds or less. For these buses, the vehicle must have windows or other emergency exits that meet the requirements set out in paragraphs S5.2.2, or S5.3 through 5.5 of the Standard. If the vehicle's emergency exits are standard, roll-down windows, or the vehicle's entrance and exit doors, then these exits must meet the specifications of S5.2.2(b). Under that provision, the windows and doors must be manually operable, and must open to a position that provides a specified area for getting out. Note that under S5.5.1, these exits do not have to meet Standard 217 marking requirements. The agency has determined that people who are old enough to read instructions generally are familiar with the operation of standard, roll-down windows and doors, and that there is little justification for requiring emergency exit markings for these exits. (40 FR 17266, April 18, 1975.)

If the vehicle's emergency exits are push-out windows or some other emergency exit, then the vehicle must comply with paragraphs S5.3 through S5.5. A manufacturer must label these exits under S5.5 because they are specially-installed emergency exits whose means of operation may not be obvious to the passengers.

School Buses

A front entrance door can not serve as a required emergency exit in a school bus, regardless of the vehicle's weight. Paragraph S5.2.3 of Standard 217 requires all school buses to have either (1) one rear emergency door, or (2) "one emergency door on the vehicle's left side that is in the rear half of the bus passenger compartment and is hinged on its forward side, and one push-out window." A manufacturer who chooses to meet school bus emergency exit requirements under the second option could not use the front entrance door as a required emergency exit under Standard 217, since that door would not be in the rear half of the passenger compartment. However, if a manufacturer chose to install an "additional" emergency exit such as a front entrance door, NHTSA regulations would not prohibit installing this exit. As the agency long has held, any "extra" emergency exit installed in a school bus must comply with Standard 217 provisions applicable to emergency exits in buses other than school buses.

Please understand that this letter addresses only Standard 217, and does not address or interpret any Federal Motor Carrier regulations. If you have any questions about those regulations, you should contact the Federal Highway Administration.

I hope you find this information helpful. If you have further questions, please contact Joan F. Tilghman of my staff, at (202) 366-2992.

Sincerely,

Erika Z. Jones Chief Counsel

Enclosure

ref:217 d:6/30/88

ID: nht71-4.34

DATE: 10/29/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Rosenstein; Livingston; Fist & Rengold

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of October 12, 1971, concerning the Defect Reports regulations (49 CFR Part 573), published February 17, 1971 (36 F.R. 3054), in which you request an interpretation of "produced" as used in @ 573.5(b) of the regulations. You state you believe that the term refers only to vehicles that have been invoiced and sold, or ready to be sold to a customer, and ask whether this would include vehicles retained by the manufacturer for demonstration or consignment purposes.

As used in the regulation "produced" refers to the date of the vehicle's manufacture. The agency takes the position that a vehicle is manufactured when the final stage of manufacture at its place of main assembly is completed. Thus, neither invoicing for sale nor sale are the points in time at which production is determined under the regulation.

With reference to whether demonstration or consignment vehicles must be included, any vehicle manufactured for use on the public roads must be included, and this includes both demonstration and consignment vehicles as those terms are generally understood. Only vehicles that are not to be used on the public roads, such as, for example, those manufactured or chosen for crash testing, need not be reported.

ID: aiam3944

Dear Mr. Hawkins: This responds to your letter asking about Federal Motor Vehicle Safet Standard No. 207, *Seating Systems*. You asked whether buses are excluded from the requirements of section S4.2, section S4.3, and/or the static testing procedures of section S5. You also asked whether there are any other standards which provide criteria for the testing of seating systems on buses. The answers to your questions are provided below.; Section S2 of Standard No. 207 provides that the standard applies t buses (among other vehicle types). Section S4.2, *General performance requirements*, provides that '(w)hen tested in accordance with S5., each occupant seat other than a side- facing seat or a passenger seat on a bus, shall withstand' specified forces. Passenger seats on a bus are thus excluded from the requirements of section S4.2. However, the driver's seat on a bus is not excluded from the requirements of that section. The testing procedures of section S5 are only relevant to seats which are subject to the general performance requirements of section S4.2.; Similarly, section S4.3, *Restraining device for hinged or foldin seats or seat backs*, provides that '(e)xcept for a passenger seat in a bus or a seat having a back that is adjustable only for the comfort of its occupants, a hinged or folding occupant seat or occupant seat back shall' meet specified requirements. Passenger seats on a bus are thus excluded from the requirements of section S4.3. Assuming that a hinged or folding occupant seat or occupant seat back were provided for the driver, it would not be excluded from the requirements of that section unless it had a back that was adjustable only for the comfort of its occupant.; With respect to your last question, Federal Motor Vehicle Safet Standard No. 222, *School Bus Passenger Seating and Crash Protection*, specifies criteria for the testing of school bus passenger seats. That standard is not applicable to buses other than school buses. The agency does not have any other standards which provide criteria for testing seating systems of buses.; Sincerely, Jeffrey R. Miller, Chief Counsel

ID: 22036.ztv

Mr. Rodney Ehrlich
V.P. Engineering
Wabash National Corporation
P.O. Box 6129
Lafayette, IN 47903






Dear Mr. Ehrlich:

This is in reply to your three letters of August 8, 2000, asking for interpretations of Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices and Associated Equipment.

1.   "Front Clearance Lamp Interpretation for van trailers over 80" wide"

You would like to use a combination front clearance and side marker lamp that would be mounted on the side of a van trailer at the top. You relate that it will be "recessed into the top rail, as far forward as practicable and still protected" from damage from tree limbs. You reference S5.3.1.1.1 of Standard No. 108 and express your belief that "the alternate mounting is permitted whereby the front inboard 45-degree requirement can be waived if the lamp is mounted for increased protection."

You are correct. Table II requires clearance lamps to be mounted "on the front." However, S5.3.1.1.1 specifies in pertinent part that "clearance lamps may be located at a location other than on the front . . . for protection from damage during normal operation of the vehicle, and at such a location they need not meet the photometric output at any test point that is 45 degrees inboard" (they are, however, required to meet all other test points specified). We note that the location you describe on a van trailer would also appear to meet the other requirements for clearance lamps, that they be located to indicate the overall width of the vehicle and as close to the top as practicable.

2.   "Sources of Stop Lamp Activation"

3.   "Can Stop Lamps be activated upon actuation of the trailer emergency braking system"

You have asked whether means other than application of the service brakes may be used to activate the stop lamps on a semi trailer. You point out that "today's ABS (antilock braking system) can be used to sense any deceleration rate and thus be used to apply the stop lamps in all braking' situations." You also point out that "another form of braking is the emergency brake that currently does not activate the stop lamps when applied," and ask whether the emergency brake system could be used for this purpose.

Your questions are similar to those we addressed recently in letters of May 26, 2000, to Eugene Farber and C. Thomas Terry, copies enclosed. Mr. Farber had asked whether it was permissible to illuminate the stop lamps when the brakes are automatically applied. We replied that when the specific purpose of a brake application is to diminish vehicle speed, the stop lamps must be illuminated. Mr. Farber had also asked whether it was permissible to illuminate the stop lamps when other mechanisms such as transmission downshifting or engine retarders are used to achieve vehicle decelerations in excess of the normally achievable coast-down deceleration. We replied that it was permissible to illuminate the stop lamps, but not required. Our letter to Mr. Farber references a letter of April 10, 1992, to Lance Watt on the same subject, and I am enclosing a copy of that as well.

You would like to install a trailer-mounted pressure switch that would activate the stop lamps when the emergency brake is activated and "significant deceleration of the vehicle can occur." As you will understand from our previous interpretations, it is permissible for the stop lamps to be activated upon activation of the trailer emergency braking system. You will note that the letter to Mr. Terry refers to his petition for an amendment to Standard No. 108. Mr. Terry petitioned for rulemaking to provide for automatic activation of the stop lamps when a certain rate of deceleration is reached. After review, the agency granted this petition in mid-September. As provided by 49 CFR 552.9(a), the agency will commence a rulemaking proceeding in accordance with applicable NHTSA and statutory procedures.

If you have any questions, you may refer them to Taylor Vinson of this Office (202-366-5263).

Sincerely,

Frank Seales, Jr.
Chief Counsel

Enclosures

ref:108
d.9/29/00

ID: aiam4002

Dear Mr. Chikada: This is in response to your letter of June 27, 1985, to the forme Chief Counsel of this agency, Frank Berndt, asking for an interpretation regarding Figure 4-1 of Motor Vehicle Safety Standard No. 108.; With reference to a two- lamp system headlamp with two reflectors, yo have asked which of three specified Points should be regarded as the 'center of aiming pattern' within the meaning of Figure 4-1. The answer is Point B, the center of the bulb for the lower beam. NHTSA provided a clarification of this in the final rule permitting two-bulb replaceable bulb headlighting systems, published on May 22, 1985. I enclose a copy for your information. In it, the agency remarked that 'NHTSA expects the aiming pads to be located on the optical axis of the lower beam portion of the headlamp when only one light source is used for the lower beam.'; Sincerely, Jeffrey R. Miller, Chief Counsel

ID: nht79-2.4

DATE: 03/28/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Cars & Concepts, Inc.

TITLE: FMVSS INTERPRETATION

ATTACHMT: 4/21/76 letter from S.P. Wood to Nissan Motor Co., Ltd.

TEXT:

March 28, 1979

Mr. Moe Pare, Jr. Director of Design Cars & Concepts, Inc. 12500 E. Grand River Brighton, Michigan 48116

Dear Mr. Pare:

This responds to your March 2, 1979, letter concerning the definition of the vehicle sub-classification, "convertible." your letter included several Figures of various vehicle designs and asked whether each would be considered a "convertible" by the National Highway Traffic Safety Administration.

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 rear roof support rearward of the "B" pillar position) by a fixed rigid structural member. Therefore, passenger cars equipped with a "sun roof" or a "Hurst hatch roof" do not qualify as convertibles, because they have a fixed, rigid structural member in the described location (April 21, 1976, letter of interpretation enclosed). This interpretation applies, moreover, whether the rigid structural member joining the "A" and "B" pillars is a hidden reinforcing component or whether the structural member is part of the exterior roof panel.

Given this interpretation, only the Fiat X-19 vehicle design illustrated in your Figure 5 would qualify as a "convertible." Each vehicle design in your other illustrations (Figures 1, 2, 3, 4, 6, 7, 8 and 9) include fixed, rigid structural components joining the "A" and "B" pillar sections of the vehicles and, therefore, would not be classified as convertibles. Likewise, the designs would not be considered "open-body type vehicles" (49 CFR 571.3) for the same reason; the structural member, whether hidden or not, would be considered part of the vehicle top. Also, I would point out that the "open-body vehicle" designation generally refers to multi-purpose passenger vehicles such as "jeeps" or "dune buggies."

I hope this clarification is responsive to your inquiry. If you have any further questions please contact Hugh Oates of my office (202-426-2992).

Sincerely,

Frank Berndt Acting Chief Counsel

Enclosure (See 4/21/76 letter from S.P. Wood to Nissan Motor Co., Ltd.)

March 2, 1979

Mr. Hugh Oates Office of the Chief Council N.H.T.S.A. 400 Seventh Street S.W. Washington, D.C. 20590

Dear Hugh:

Per our telephone conversation, I have become confused regarding the legal definition for a "convertible body". At one time I had felt that any vehicle with structure extending from "A" to "B" pillar would not be classified as a convertible; however, I am unable to locate documentation to that effect.

The only definition I can locate is carried in Part 571.3(b) of the Federal Motor Vehicle Safety standards, which defines an "open-body type vehicle" (a term which is used interchangeably with "convertible" in FMVSS No. 208.S4.1.1.3.2. and No. 208.S4.1.2.3.2.) as a vehicle with no occupant compartment top or one which can be installed or removed by the user at his convenience.

By both definitions, I feel that Figure 1, showing a Mazda RX7 with a removable roof panel, does not qualify as a convertible. As this vehicle has roof side rail structures that go directly from "A" to "B" pillar and a full exterior roof stamping, this car, I feel, ought be classified as a coupe.

Similarly, the Renault Gordini (Figure 2) has a much larger opening (extending from "A" to "C" pillar); however, as the "opening" is still surrounded by roof structure (in plan view), I feel secure in assuming that such a vehicle is a coupe also.

Please look at Figures 3 and 4. These photographs show a 1977 Pontiac Grand Prix with a Hurst hatch roof, and a 1979 Chrysler Cordoba with an ASC (American Sunroof Corporation) hatch roof installation. These roofs are similar in that both rely on two "U"-shape openings cut into the roof in a manner that would allow an exterior "roof panel section" along the vehicle's longitudinal centerline. These roofs are installed on "coupe" bodies, but as part of this installation the entire "occupant compartment top" /refer to Part 571.3(b)/, from left, side DLO to right, side DLO, is never removed (either by the manufacturer or user). Again, using both mentioned definitions, I feel these vehicles fall outside the classification of a convertible or "open-body type vehicle".

Now examine Figure 5 showing a Fiat X-19 targa top. As is clear from the photo, this vehicle has "A" and "B" pillars with transverse (to the plan view centerline) structure extending from both "A" and "B" pillars, but clearly has a completely removable "occupant compartment top" with no structure at all between the "A" and "B" pillars (above the beltline). Using both above definitions, this car is clearly a convertible.

Figure 6 shows the roof structure employed on a 1977 Corvette. While this car does have centerline reinforcement member, it is not part of the exterior roof panel sections. Because this center member is not part of the roof panel, and is usually hidden from view, I feel this component takes on the character of a "central (in side view)" reinforcing member and is therefore more closely related to the conventional old style convertible chassis reinforcements than the vehicle's occupant compartment top.

Finally I have come to my real area of concern, shown in Figures 7, 8, and 9. These Cars & Concepts roofs have been granted U.S. Patent No. 4,138,155 which is based largely on the Cars & Concepts installation requirement that the entire occupant compartment top (from right, side DLO to left, side DLO) is completely removed. Similar to the Corvette, our roof also uses a hidden centerline structure which takes the place of the needed chassis reinforcements. Also similar is the "panel to panel" configuration used in our roofs (see Page 2 of Figure 6). These two removable panels comprise (virtually) the entire "occupant compartment top". A basic difference between our roof and that of the Corvette is that our roof has a full width exterior roof panel at the windshield header (as does the X-19), and Chevrolet never actually removes the entire occupant compartment top (including center reinforcement; this center reinforcement is part of the windshield header structure and is basic to the vehicle's construction) of the Corvette.

To summarize, it seems obvious to me that a Fiat X-19 is a convertible, while a coupe with a sunroof is not. It does not seem to me, however, that a car with a Hurst hatch which does not remove the entire occupant compartment top (roof panel) is a convertible. By the same token, a Corvette never exists without an overhead centerline reinforcement member, but the entire exterior roof portion is removable creating a vehicle that fits the N.H.T.S.A.'s criterion for an "open-body". Finally on the Cars & Concepts roof installation, the entire occupant section of a coupe is removed (at this stage it is clearly a targa type vehicle); then in place of chassis reinforcement, we add a centerline structural member and install a removable two piece occupant compartment top.

My question obviously is: between the Fiat, the Corvette, Hurst's roof, and our roof, which (if any) would the N.H.T.S.A. consider a convertible? Thank you for your consideration; please call with any questions.

Sincerely,

Moe Pare, Jr. Director of Design

MP/dma

cc: D. Draper

ID: nht79-1.16

DATE: 10/25/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: SEV Corporation

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. H. J. T. Young Vice President - Technical Affairs SEV Corporation 33201 Harper Avenue St. Clair Shores, Michigan 48082

Dear Mr. Young:

This is in reply to your letter of September 24, 1979, to Mr. Vinson of this office asking for an interpretation of Federal Motor Vehicle Safety Standard No. 108.

You referred to the SAE standard on motorcycle headlamps, J584, which specifies that the "bulb or unit shall be operated at its rated voltage during the photometric test." You asked whether the "rated voltage" of J584 is the same rated voltage of ECE Regulation 37 when the bulb in question is a European bulb bearing an E mark signifying compliance with Regulation 37.

The term "rated voltage" is not defined by J584 or by the corresponding standard on sealed beam headlamps, J579c. It is our opinion, however, that "rated voltage" is the equivalent of "design voltage" on the basis of the SAE standard that covers bulbs used in sealed beam headlamps, J573d, Lamps Bulbs and Sealed Units. Table 2 of J573d lists voltages for such headlamps under the heading of "Design."

We realize that your question arises in the context of recent testing by NHTSA of Cibie headlamps, incorporating European H4 halogen bulbs, for compliance with the requirements of Standard No. 108 for motorcycle headlighting. NHTSA tested these headlamps at 12.8 volts and discovered that the maximum allowable 5000 candela at test point 4D-V was exceeded by many of the lamps tested. You raised the question whether NHTSA should not have tested at 12 volts, the "rated value" given by Regulation 37 for the H4 bulb, at which value all lamps tested by NHTSA would have complied at test point 4D-V.

We do not believe that NHTSA is required by J589 to test the H4 bulb at 12 volts. Regulation 37 specifies a "test voltage" of 13.2 for the H4 bulb, a point apparently recognized by EFPE Company's catalogue "Turned on Lighting" which gives wattage figures for the headlamps in question "at 13.2 design volts as specified by the bulb manufacturer." If anything, NHTSA was overly conservative in testing its lamps at 12.8 volts, for it is apparent that had it tested at 13.2 volts even more failures would have occurred.

As Roman Brooks explained to you, it has been the European practice as nearly as we can determine to test the H4 bulb at 12.8 volts, apparently in recognition that the higher voltage levels are closer to those generated by the electrical systems of the motor vehicles on which the headlamps are installed. Given this fact and Regulation 37's specification of 13.2 test volts, we do not believe that a lamp manufacturer could successfully argue in court that J584 was ambiguous and should be construed against NHTSA in any attempt by this agency to enforce motorcycle headlighting requirements on the basis of results of tests conducted at 12.8 volts.

Sincerely,

Frank Berndt Chief Counsel