49 C.F.R. § 571.108
Current through November 30, 2024
Adaptive driving beam means a long-range light beam for forward visibility, which automatically modifies portions of the projected light to reduce glare to traffic participants on an ongoing, dynamic basis.
Aiming plane means a plane defined by the surface of the three aiming pads on the lens.
Aiming reference plane means a plane which is perpendicular to the longitudinal axis of the vehicle and tangent to the forwardmost aiming pad on the headlamp.
Aiming screws are the horizontal and vertical adjusting screws with self-locking features used to aim and retain a headlamp unit in the proper position.
Axis of reference means the characteristic axis of the lamp for use as the direction of reference (H = 0°, V = 0°) for angles of field for photometric measurements and for installing the lamp on the vehicle.
Backup lamp means a lamp or lamps which illuminate the road to the rear of a vehicle and provide a warning signal to pedestrians and other drivers when the vehicle is backing up or is about to back up.
Beam contributor means an indivisible optical assembly including a lens, reflector, and light source, that is part of an integral beam headlighting system and contributes only a portion of a headlamp beam.
Cargo lamp is a lamp that is mounted on a multipurpose passenger vehicle, truck, or bus for the purpose of providing illumination to load or unload cargo.
Clearance lamps are lamps which show to the front or rear of the vehicle, mounted on the permanent structure of the vehicle as near as practicable to the upper left and right extreme edges to indicate the overall width and height of the vehicle.
Coated materials means a material which has a coating applied to the surface of the finished sample to impart some protective properties. Coating identification means a mark of the manufacturer's name, formulation designation number, and recommendations for application.
Color Fundamental definitions of color are expressed by Chromaticity Coordinates according to the CIE 1931 Standard Colorimetric System, as described in the CIE 1931 Chromaticity Diagram (incorporated by reference, see § 571.5 ).
Color bleeding means the migration of color out of a plastic part onto the surrounding surface.
Combination clearance and side marker lamps are single lamps which simultaneously fulfill the requirements of clearance and side marker lamps.
Combination headlamp means a headlamp that is a combination of two different headlamp types chosen from a type F sealed beam headlamp, an integral beam headlamp, or a replaceable bulb headlamp.
Cracking means a separation of adjacent sections of a plastic material with penetration into the specimen.
Crazing means a network of apparent fine cracks on or beneath the surface of materials.
Cutoff means a generally horizontal, visual/optical aiming cue in the lower beam that marks a separation between areas of higher and lower luminance.
Daytime running lamps (DRLs) are steady burning lamps that are used to improve the conspicuity of a vehicle from the front and front sides when the regular headlamps are not required for driving.
Delamination means a separation of the layers of a material including coatings.
Design voltage means the voltage used for design purposes.
Direct reading indicator means a device that is mounted in its entirety on a headlamp or headlamp aiming or headlamp mounting equipment, is part of a VHAD, and provides information about headlamp aim in an analog or digital format.
Effective light-emitting surface means that portion of a lamp that directs light to the photometric test pattern, and does not include transparent lenses, mounting hole bosses, reflex reflector area, beads or rims that may glow or produce small areas of increased intensity as a result of uncontrolled light from an area of 1/2° radius around a test point.
Effective projected luminous lens area means the area of the orthogonal projection of the effective light-emitting surface of a lamp on a plane perpendicular to a defined direction relative to the axis of reference. Unless otherwise specified, the direction is coincident with the axis of reference.
Exposed means material used in lenses or optical devices exposed to direct sunlight as installed on the vehicle.
Filament means that part of the light source or light emitting element(s), such as a resistive element, the excited portion of a specific mixture of gases under pressure, or any part of other energy conversion sources, that generates radiant energy which can be seen.
Flash means a cycle of activation and deactivation of a lamp by automatic means continuing until stopped either automatically or manually.
Fully opened means the position of the headlamp concealment device in which the headlamp is in the design open operating position.
H-V axis means the line from the center of the principal filament of a lamp to the intersection of the horizontal (H) and vertical (V) lines of a photometric test screen.
Haze means the cloudy or turbid appearance of an otherwise transparent specimen caused by light scattered from within the specimen or from its surface.
Headlamp means a lighting device providing an upper and/or a lower beam used for providing illumination forward of the vehicle.
Headlamp concealment device means a device, with its operating system and components, that provides concealment of the headlamp when it is not in use, including a movable headlamp cover and a headlamp that displaces for concealment purposes.
Headlamp mechanical axis means the line formed by the intersection of a horizontal and a vertical plane through the light source parallel to the longitudinal axis of the vehicle. If the mechanical axis of the headlamp is not at the geometric center of the lens, then the location will be indicated by the manufacturer on the headlamp.
Headlamp test fixture means a device designed to support a headlamp or headlamp assembly in the test position specified in the laboratory tests and whose mounting hardware and components are those necessary to operate the headlamp as installed in a motor vehicle.
Headlighting system midpoint means the intersection of a horizontal plane through the test vehicle's headlamp light sources, a vertical plane through the test vehicle's headlamp light sources and a vertical plane through the test vehicle's centerline.
High-mounted stop lamp means a lamp mounted high and possibly forward of the tail, stop, and rear turn signal lamps intended to give a steady stop warning through intervening vehicles to operators of following vehicles.
Identification lamps are lamps used in groups of three, in a horizontal row, which show to the front or rear or both, having lamp centers spaced not less than [6 in] 15.2 mm nor more than [12 in] 30.4 mm apart, mounted on the permanent structure as near as practicable to the vertical centerline and the top of the vehicle to identify certain types of vehicles.
Integral beam headlamp means a headlamp (other than a standardized sealed beam headlamp designed to conform to paragraph S10.13 or a replaceable bulb headlamp designed to conform to paragraph S10.15) comprising an integral and indivisible optical assembly including lens, reflector, and light source, except that a headlamp conforming to paragraph S10.18.8 or paragraph S10.18.9 may have a lens designed to be replaceable.
License plate lamp means a lamp used to illuminate the license plate on the rear of a vehicle.
Lower beam means a beam intended to illuminate the road and its environs ahead of the vehicle when meeting or closely following another vehicle.
Material means the type and grade of plastics, composition, and manufacturer's designation number and color.
Mechanically aimable headlamp means a headlamp having three pads on the lens, forming an aiming plane used for laboratory photometric testing and for adjusting and inspecting the aim of the headlamp when installed on the vehicle.
Motor driven cycle means every motorcycle, including every motor scooter, with a motor which produces not more than 5 horsepower, and every bicycle with motor attached.
Motorcycle or motor driven cycle headlamp means a major lighting device used to produce general illumination ahead of the vehicle.
Mounting ring means the adjustable ring upon which a sealed beam unit is mounted.
Mounting ring (type F sealed beam) means the adjustable ring upon which a sealed beam unit is mounted and which forces the sealed beam unit to seat against the aiming ring when assembled into a sealed beam assembly.
Multiple compartment lamp means a device which gives its indication by two or more separately lighted areas which are joined by one or more common parts, such as a housing or lens.
Multiple lamp arrangement means an array of two or more separate lamps on each side of the vehicle which operate together to give a signal.
Optically combined means a lamp having a single or two filament light source or two or more separate light sources that operate in different ways, and has its optically functional lens area wholly or partially common to two or more lamp functions.
Overall width means the nominal design dimension of the widest part of the vehicle, exclusive of signal lamps, marker lamps, outside rearview mirrors, flexible fender extensions, mud flaps, and outside door handles determined with doors and windows closed, and the wheels in the straight-ahead position. Running boards may also be excluded from the determination of overall width if they do not extend beyond the width as determined by the other items excluded by this definition.
Parking lamps are lamps on both the left and right of the vehicle which show to the front and are intended to mark the vehicle when parked or serve as a reserve front position indicating system in the event of headlamp failure.
Protected means material used in inner lenses for optical devices where such lenses are protected from exposure to the sun by an outer lens made of materials meeting the requirements for exposed plastics.
Rated voltage means the nominal circuit or vehicle electrical system voltage classification.
Reflex reflectors are devices used on vehicles to give an indication to approaching drivers using reflected light from the lamps of the approaching vehicle.
Remote reading indicator means a device that is not mounted in its entirety on a headlamp or headlamp aiming or headlamp mounting equipment, but otherwise meets the definition of a direct reading indicator.
Replaceable bulb headlamp means a headlamp comprising a bonded lens and reflector assembly and one or two replaceable light sources, except that a headlamp conforming to paragraph S10.18.8 or paragraph S10.18.9 may have a lens designed to be replaceable.
Replaceable light source means an assembly of a capsule, base, and terminals that is designed to conform to the requirements of appendix A or appendix B of 49 CFR Part 564 Replaceable Light Source Information of this Chapter.
Retaining ring means the clamping ring that holds a sealed beam unit against a mounting ring.
Retaining ring (type F sealed beam) means the clamping ring that holds a sealed beam unit against a mounting ring, and that provides an interface between the unit's aiming/seating pads and the headlamp aimer adapter (locating plate).
School bus signal lamps are alternately flashing lamps mounted horizontally both front and rear, intended to identify a vehicle as a school bus and to inform other users of the highway that such vehicle is stopped on the highway to take on or discharge school children.
Sealed beam headlamp means an integral and indivisible optical assembly including the light source with "SEALED BEAM" molded in the lens.
Sealed beam headlamp assembly means a major lighting assembly which includes one or more sealed beam units used to provide general illumination ahead of the vehicle.
Seasoning means the process of energizing the filament of a headlamp at design voltage for a period of time equal to 1% of design life, or other equivalent method.
Semiautomatic headlamp beam switching device is one which provides either automatic or manual control of beam switching at the option of the driver. When the control is automatic the headlamp beams switch automatically. When the control is manual, the driver may obtain either the lower beam or the upper beam manually regardless of the conditions ahead of the vehicle.
Side marker lamps are lamps which show to the side of the vehicle, mounted on the permanent structure of the vehicle as near as practicable to the front and rear edges to indicate the overall length of the vehicle. Additional lamps may also be mounted at intermediate locations on the sides of the vehicle.
Stop lamps are lamps giving a steady light to the rear of a vehicle to indicate a vehicle is stopping or diminishing speed by braking.
Taillamps are steady burning low intensity lamps used to designate the rear of a vehicle.
Test voltage means the specified voltage and tolerance to be used when conducting a test.
Transition zone means the portion of an adaptive driving beam that occurs between an area of reduced intensity and an area of unreduced intensity.
Turn signal lamps are the signaling element of a turn signal system which indicates the intention to turn or change direction by giving a flashing light on the side toward which the turn will be made.
Turn signal flasher means a device which causes a turn signal lamp to flash as long as it is turned on.
Turn signal operating unit means an operating unit that is part of a turn signal system by which the operator of a vehicle causes the signal units to function.
Upper beam means a beam intended primarily for distance illumination and for use when not meeting or closely following other vehicles.
Vehicle headlamp aiming device or VHAD means motor vehicle equipment, installed either on a vehicle or headlamp, which is used for determining the horizontal or vertical aim, or both the vertical and horizontal aim of the headlamp.
Vehicular hazard warning signal flasher means a device which, as long as it is turned on, causes all the required turn signal lamps to flash.
Vehicular hazard warning signal operating unit means a driver controlled device which causes all required turn signal lamps to flash simultaneously to indicate to approaching drivers the presence of a vehicular hazard.
Visually/optically aimable headlamp means a headlamp which is designed to be visually/optically aimable in accordance with the requirements of paragraph S10.18.9 of this standard.
S8.1.1P3 Alternative side reflex reflector material. Reflective material conforming to GSA Federal Specification L-S-300 (incorporated by reference, see § 571.5 ), may be used for side reflex reflectors if this material as used on the vehicle, meets the performance requirements of Table XVI-a.
y = 0.33 (yellow boundary)
y = 0.98 - x (purple boundary)
y = 0.39 (red boundary)
y = 0.79 - 0.67x (white boundary)
y = x - 0.12 (green boundary)
x = 0.31 (blue boundary)
y = 0.44 (green boundary)
x = 0.50 (yellow boundary)
y = 0.15 + 0.64x (green boundary)
y = 0.38 (red boundary)
y = 0.05 + 0.75x (purple boundary)
y = 0.73 - 0.73x (yellow boundary)
x = 0.63y - 0.04 (white boundary)
y = 0.50 - 0.50x (blue boundary)
y = 0.07 + 0.81x (green boundary)
x = 0.40 - y (white boundary)
x = 0.13 + 0.60y (violet boundary)
y = 0.32 (green boundary)
x = 0.16 (white boundary)
x = 0.40 - y (white boundary)
x = 0.13 + 0.60y (violet boundary)
| Test position (degrees) | Dim (cd at 100 ft) | Hold (cd at 100 ft) |
| H V | Adjust to 15 | 1.5 min to 3.75 max. |
| H 2L | 25 max | 1.5 min. |
| H 4L | 40 max | 1.5 min. |
| H 6L | 75 max | 1.5 min. |
| H 2R | 25 max | 1.5 min. |
| H 5R | 150 max to 40 min | 1.5 min. |
| 1D V | 30 max | 1.5 min. |
| 1U V | 30 max | 1.5 min. |
Table I-a-Required Lamps and Reflective Devices
| Lighting device | Number and color | Mounting location | Mounting height | Device activation |
| All Passenger Cars, Multipurpose Passenger Vehicles (MPV), Trucks, and Buses | ||||
| Lower Beam Headlamps | White, of a headlighting system listed in Table II | On the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 55.9 cm nor more than 137.2 cm | The wiring harness or connector assembly of each headlighting system must be designed so that only those light sources intended for meeting lower beam photometrics are energized when the beam selector switch is in the lower beam position, and that only those light sources intended for meeting upper beam photometrics are energized when the beam selector switch is in the upper beam position, except for certain systems listed in Table II and semiautomatic headlamp beam switching devices certified to S9.4.1.6. Steady burning, except that may be flashed for signaling purposes or (for semiautomatic headlamp beam switching devices certified to S9.4.1.6) vary in intensity for adaptive driving beam functionality. |
| Upper Beam Headlamps | White, of a headlighting system listed in Table II | On the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 22 inches (55.9 cm) nor more than 54 inches (137.2 cm) | |
| Turn Signal Lamps | 2 Amber | At or near the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 15 inches, nor more than 83 inches | Flash when the turn signal flasher is actuated by the turn signal operating unit. |
| 2 Amber or red Truck tractor exception, see S6.1.1.3 | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable | |||
| Taillamps | 2 Red | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 15 inches, nor more than 72 inches | Steady burning. Must be activated when the headlamps are activated in a steady burning state or the parking lamps on passenger cars and MPVs, trucks, and buses less than 80 inches in overall width are activated. May be activated when the headlamps are activated at less than full intensity as Daytime Running Lamps (DRL). |
| Stop Lamps | 2 Red | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 15 inches, nor more than 72 inches | Steady burning. Must be activated upon application of the service brakes. When optically combined with a turn signal lamp, the circuit must be such that the stop signal cannot be activated if the turn signal lamp is flashing. May also be activated by a device designed to retard the motion of the vehicle. |
| Side Marker Lamps | 2 Amber | On each side as far to the front as practicable | Not less than 15 inches | Steady burning except may be flashed for signaling purposes. Must be activated when the headlamps are activated in a steady burning state or the parking lamps on passenger cars and MPVs, trucks, and buses less than 80 inches in overall width are activated. |
| 2 Red (not required on truck tractor). | On each side as far to the rear as practicable | |||
| Reflex Reflectors | 2 Amber | On each side as far to the front as practicable | Not less than 15 inches, nor more than 60 inches | Not applicable. |
| 2 Red (not required on truck tractor). | On each side as far to the rear as practicable | |||
| 2 Red | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable On a truck tractor may be mounted on the back of the cab not less than 4 inches above the height of the rear tires. | |||
| Backup Lamp | 1 White Additional lamps permitted to meet requirements | On the rear | No requirement | Steady burning. Must be activated when the ignition switch is energized and reverse gear is engaged. Must not be energized when the vehicle is in forward motion. |
| License Plate Lamp | 1 White Additional lamps permitted to meet requirements | On the rear to illuminate license plate from top or sides | No requirement | Steady burning. Must be activated when the headlamps are activated in a steady burning state or when the parking lamps on passenger cars and MPVs, trucks, and buses less than 80 inches in overall width are activated. |
| Additional Lamps Required on All Passenger Cars, and on Multipurpose Passenger Vehicles (MPV), Trucks, and Buses, Less Than 2032 MM in Overall Width | ||||
| Parking lamps | 2 Amber or white | On the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 15 inches, nor more than 72 inches | Steady burning. Must be activated when the headlamps are activated in a steady burning state. |
| Additional Lamp(s) Required on All Passenger Cars, and on Multipurpose Passenger Vehicles (MPV), Trucks, and Buses, Less Than 2032 MM in Overall Width and With a GVWR of 10,000 Lbs or Less | ||||
| High mounted stop lamp | 1 Red, or 2 red where exceptions apply. See Section 6.1.1.2 | On the rear including glazing, with the lamp center on the vertical centerline as viewed from the rear | Not less than 34 inches except for passenger cars. See Section 6.1.4.1 | Steady burning. Must only be activated upon application of the service brakes or may be activated by a device designed to retard the motion of the vehicle. |
| Additional Lamps and Reflective Devices Required on All Passenger Cars, Multipurpose Passenger Vehicles (MPV), Trucks, and Buses, 30 Feet or Longer | ||||
| Intermediate side marker lamps | 2 Amber | On each side located at or near the midpoint between the front and rear side marker lamps | Not less than 15 inches | Steady burning except may be flashed for signaling purposes. Must be activated when the headlamps are activated in a steady burning state or when the parking lamps on passenger cars and MPVs, trucks, and buses less than 80 inches in overall width are activated. |
| Intermediate side reflex reflectors | 2 Amber | On each side located at or near the midpoint between the front and rear side reflex reflectors | Not less than 15 inches, nor more than 60 inches | Not applicable. |
| Additional Lamps Required on All Multipurpose Passenger Vehicles (MPV), Trucks, and Buses, 2032 MM or More in Overall Width | ||||
| Clearance lamps | 2 Amber | On the front to indicate the overall width of the vehicle, or width of cab on truck tractor, at the same height, symmetrically about the vertical centerline May be located at a location other than the front if necessary to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle. | As near the top as practicable | Steady burning. |
| 2 Red (not required on truck tractor) | On the rear to indicate the overall width of the vehicle, at the same height, symmetrically about the vertical centerline May be located at a location other than the rear if necessary to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle. | As near the top as practicable, except where the rear identification lamps are mounted at the extreme height of the vehicle. Practicability of locating lamps on the vehicle header is presumed when the header extends at least 25 mm (1 inch) above the rear doors. | Steady burning. | |
| Identification lamps | 3 Amber | On the front, at the same height, as close as practicable to the vertical centerline, with lamp centers spaced not less than 6 inches or more than 12 inches apart | As near the top of the vehicle or top of the cab as practicable | Steady burning. |
| 3 Red (not required on truck tractor) | On the rear, at the same height, as close as practicable to the vertical centerline, with lamp centers spaced not less than 6 inches or more than 12 inches apart | As near the top as practicable Practicability of locating lamps on the vehicle header is presumed when the header extends at least 25 mm (1 inch) above the rear doors. | Steady burning. | |
| Additional Lamps Required on All School Buses Except Multifunction School Activity Buses | ||||
| Signal warning lamps | 2 Red plus 2 amber optional | On the front of the cab as far apart as practicable, but in no case shall the spacing between lamps be less than 40 inches Amber lamps, when installed, at the same height as and just inboard of the red lamp. | As high as practicable but at least above the windshield | Flashing alternately between 60 to 120 cycles per minute, with an activation period sufficient to allow the lamp to reach full brightness, when actuated by a manual switch. Amber lamps, when installed, may only be activated by manual or foot operation, and must be automatically deactivated and the red lamps must be automatically activated when the bus entrance door is opened. |
| 2 Red plus 2 amber optional | On the rear cab as far apart as practicable, but in no case shall the spacing between lamps be less than 40 inches Amber lamps, when installed, at the same height as and just inboard of the red lamp. | As high as practicable but at least above the top of any side window opening | Flashing alternately between 60 to 120 cycles per minute, with an activation period sufficient to allow the lamp to reach full brightness, when actuated by a manual switch. Amber lamps, when installed, may only be activated by manual or foot operation, and must be automatically deactivated and the red lamps must be automatically activated when the bus entrance door is opened. | |
| Daytime Running Lamps Permitted But Not Required on Passenger Cars, Multipurpose Passenger Vehicles (MPV), Trucks, and Buses | ||||
| Daytime running lamp (DRL) | 2 identically colored either white, white to yellow, white to selective yellow, selective yellow, or yellow | On the front, symmetrically disposed about the vertical centerline if not a pair of lamps required by this standard or if not optically combined with a pair of lamps required by this standard | Not more than 1.067 meters above the road surface if not a pair of lamps required by this standard or if not optically combined with a pair of lamps required by this standard See S7.10.13(b) for additional height limitation. | Steady burning. Automatically activated as determined by the vehicle manufacturer and automatically deactivated when the headlamp control is in any "on" position. Each DRL optically combined with a turn signal lamp must be automatically deactivated as a DRL when the turn signal lamp or hazard warning lamp is activated, and automatically reactivated as a DRL when the turn signal lamp or hazard warning lamp is deactivated. See S7.10.10.1(c) for additional activation requirements when mounted close to, or combined with, a turn signal lamp. |
Table I-b-Required Lamps and Reflective Devices
| Lighting device | Number and color | Mounting location | Mounting height | Device activation |
| ALL TRAILERS | ||||
| Turn Signal Lamps | 2 Red or amber | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable | Not less than 15 inches, nor more than 83 inches | Flash when the turn signal flasher is actuated by the turn signal operating unit. |
| Taillamps | 2 Red or 1 red on trailers less than 30 inches wide | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable. When a single lamp is installed it must be mounted at or near the vertical centerline | Not less than 15 inches, nor more than 72 inches | Steady burning. |
| Stop Lamps | 2 Red, or 1 red on trailers less than 30 inches wide | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable. When a single lamp is installed it must be mounted at or near the vertical centerline | Not less than 15 inches, nor more than 72 inches | Steady burning. Must be activated upon application of the service brakes. When optically combined with a turn signal lamp, the circuit must be such that the stop signal cannot be activated if the turn signal lamp is flashing. May also be activated by a device designed to retard the motion of the vehicle. |
| Side Marker Lamps | 2 Amber None required on trailers less than 1829 mm [6 ft] in overall length including the trailer tongue | On each side as far to the front as practicable exclusive of the trailer tongue | Not less than 15 inches | Steady burning except may be flashed for signaling purposes. |
| 2 Red | On each side as far to the rear as practicable | Not less than 15 inches. Not more than 60 inches on trailers 2032 mm or more in overall width | ||
| Reflex Reflectors. A trailer equipped with a conspicuity treatment in conformance with S8.2 of this standard need not be equipped with reflex reflectors if the conspicuity material is placed at the locations of the required reflex reflectors | 2 Amber None required on trailers less than 1829 mm [6 ft] in overall length including the trailer tongue | On each side as far to the front as practicable exclusive of the trailer tongue | Not less than 15 inches, nor more than 60 inches | Not applicable. |
| 2 Red | On each side as far to the rear as practicable | |||
| 2 Red or 1 red on trailers less than 30 inches wide | On the rear, at the same height, symmetrically about the vertical centerline, as far apart as practicable When a single reflector is installed it must be mounted at or near the vertical centerline. | |||
| License Plate Lamp | 1 White Additional lamps permitted to meet requirements | On the rear to illuminate license plate from top or sides | No requirement | Steady burning. |
| Additional Lamps and Reflective Devices Required on all Trailers 30 Feet or Longer | ||||
| Intermediate side marker lamps | 2 Amber | On each side located at or near the midpoint between the front and rear side marker lamps | Not less than 15 inches | Steady burning except may be flashed for signaling purposes. |
| Intermediate side reflex reflectors A trailer equipped with a conspicuity treatment in conformance with S8.2 of this standard need not be equipped with reflex reflectors if the conspicuity material is placed at the locations of the required reflex reflectors | 2 Amber | On each side located at or near the midpoint between the front and rear side reflex reflectors | Not less than 15 inches, nor more than 60 inches | Not applicable. |
| Additional Lamps Required on all Trailers 2032 MM or More in Overall Width | ||||
| Clearance lamps | 2 Amber | On the front to indicate the overall width of the vehicle, at the same height, symmetrically about the vertical centerline May be located at a location other than the front if necessary to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle | As near the top as practicable | Steady burning. |
| 2 Red | On the rear to indicate the overall width of the vehicle, at the same height, symmetrically about the vertical centerline May be located at a location other than the rear if necessary to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle | As near the top as practicable, except where the rear identification lamps are mounted at the extreme height of the vehicle. Practicability of locating lamps on the vehicle header is presumed when the header extends at least 25 mm (1 inch) above the rear doors | Steady burning. | |
| 2 Amber to front and red to rear | On a boat trailer the requirement for front and rear clearance lamps may be met by installation at or near the midpoint on each side of a dual facing lamp so as to indicate the extreme width. May be located at a location other than the front and the rear if necessary to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle | As near the top as practicable | Steady burning. | |
| Identification lamps | 3 Red | On the rear, at the same height, as close as practicable to the vertical centerline, with lamp centers spaced not less than 6 inches or more than 12 inches apart | As near the top as practicable Practicability of locating lamps on the vehicle header is presumed when the header extends at least 25 mm (1 inch) above the rear doors | Steady burning. |
Table I-c-Required Lamps and Reflective Devices
| Lighting device | Number and color | Mounting location | Mounting height | Device activation |
| All Motorcycles | ||||
| Lower Beam Headlamps | White, of a headlighting system listed in S10.17 | On the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable. See additional requirements in S10.17.1.1, S10.17.1.2, and S10.17.1.3 | Not less than 22 inches (55.9 cm) nor more than 54 inches (137.2 cm) | The wiring harness or connector assembly of each headlighting system must be designed so that only those light sources intended for meeting lower beam photometrics are energized when the beam selector switch is in the lower beam position, and that only those light sources intended for meeting upper beam photometrics are energized when the beam selector switch is in the upper beam position, except for certain systems listed in Table II and semiautomatic headlamp beam switching devices certified to S9.4.1.6. Steady burning, except that may be flashed for signaling purposes or (for semiautomatic headlamp beam switching devices certified to S9.4.1.6) vary in intensity for adaptive driving beam functionality. The upper beam or the lower beam, but not both, may be wired to modulate from a higher intensity to a lower intensity in accordance with S10.17.5. |
| Upper Beam Headlamps | White, of a headlighting system listed in S10.17 | On the front, at the same height, symmetrically about the vertical centerline, as far apart as practicable. See additional requirements in S10.17.1.1, S10.17.1.2, and S10.17.1.3 | Not less than 55.9 cm nor more than 137.2 cm | |
| The upper beam or the lower beam, but not both, may be wired to modulate from a higher intensity to a lower intensity in accordance with S10.17.5 | ||||
| Turn Signal Lamps | 2 Amber. None required on a motor driven cycle whose speed attainable in 1 mile is 30 mph or less | At or near the front, at the same height, symmetrically about the vertical centerline, and having a minimum horizontal separation distance (centerline of lamps) of 16 inches. Minimum edge to edge separation distance between a turn signal lamp and headlamp is 4 inches | Not less than 15 inches, nor more than 83 inches | Flash when the turn signal flasher is actuated by the turn signal operating unit. |
| 2 Amber or red. None required on a motor driven cycle whose speed attainable in 1 mile is 30 mph or less | At or near the rear, at the same height, symmetrically about the vertical centerline, and having a minimum horizontal separation distance (centerline to centerline of lamps) of 9 inches | |||
| Minimum edge to edge separation distance between the turn signal lamp and the taillamp or stop lamp is 4 inches, when a single stop and taillamp is installed on the vertical centerline and the turn signal lamps are red | ||||
| Taillamps | 1 Red | On the rear, on the vertical centerline except that if two are used, they must be symmetrically disposed about the vertical centerline | Not less than 15 inches, nor more than 72 inches | Steady burning. |
| Must be activated when the headlamps are activated in a steady burning state. | ||||
| Stop Lamps | 1 Red | On the rear, on the vertical centerline except that if two are used, they must be symmetrically disposed about the vertical centerline | Not less than 15 inches, nor more than 72 inches | Steady burning. |
| Must be activated upon application of the service brakes. | ||||
| When optically combined with a turn signal lamp, the circuit must be such that the stop signal cannot be activated if the turn signal lamp is flashing. May also be activated by a device designed to retard the motion of the vehicle. | ||||
| Reflex Reflectors | 2 Amber | On each side as far to the front as practicable | Not less than 15 inches, nor more than 60 inches | Not applicable. |
| 2 Red | On each side as far to the rear as practicable | |||
| 1 Red | On the rear, on the vertical centerline except that, if two are used on the rear, they must be symmetrically disposed about the vertical centerline | |||
| License Plate Lamp | 1 White | On the rear to illuminate license plate | No requirement | Steady burning. |
| Additional lamps permitted to meet requirements | Must be activated when the headlamps are activated in a steady burning state. | |||
Table II-b-Headlighting Systems-Combination
| System designation | System composition | Photometry requirements reference | ||
| Table XVIII | Tables XIX-a, XIX-b, XIX-c | |||
| Upper beam mechanical and visual aim | Lower beam mech aim | Lower beam visual aim | ||
| 2 LAMP SYSTEM | A COMBINATION OF TWO DIFFERENT HEADLAMPS CHOSEN FROM; TYPE F, AN INTEGRAL BEAM HEADLAMP, OR A REPLACEABLE BULB HEADLAMP | UB2(1) | LB2M(1) | LB2V(1) |
| 4 LAMP SYSTEM | ANY COMBINATION OF FOUR DIFFERENT HEADLAMPS CHOSEN FROM; TYPE F, AN INTEGRAL BEAM HEADLAMP(3), OR A REPLACEABLE BULB HEADLAMP | UB1 | LB1M(2) | LB1V(2) |
(1) Headlamps designed to conform to the photometry requirements of UB2 and LB2M or LB2V may allow the lower beam light source(s) to remain activated when an upper beam light source is activated if the lower beam light source(s) contribute to upper beam photometric compliance.
(2) Lower beams may remain activated when upper beams are activated.
(3) Beam contributor photometric allocation formula of S14.2.5.9 may apply.
Table II-c-Headlighting Systems-Integral Beams
| System designation | Beam composition | Photometry requirements reference | ||
| Table XVIII | Tables XIX-a, XIX-b, XIX-c | |||
| Upper beam mechanical and visual aim | Lower beam mech aim | Lower beam visual aim | ||
| 2 LAMP SYSTEM | UPPER BEAM & LOWER BEAM | UB2(1) OR UB3 | LB2M(1) OR LB3M | LB2V(1) OR LB3V |
| 4 LAMP SYSTEM | UPPER BEAM | UB4 | N.A. | N.A. |
| UPPER BEAM & LOWER BEAM | UB5 | LB4M | LB2V | |
| 4 LAMP SYSTEM | UPPER BEAM (U) | UB1 | N.A. | N.A. |
| LOWER BEAM (L) | N.A.(2) | LB1M(2) | LB1V(2) | |
| 4 LAMP SYSTEM | UPPER BEAM | UB6 | N.A. | N.A. |
| LOWER BEAM | N.A.(3) | LB5M(3) | LB4V(3) | |
| BEAM CONTRIBUTOR | UPPER BEAM & LOWER BEAM | UB1(4) | LB1M(2)(4) | LB1V(2)(4) |
(1) Headlamps designed to conform to the photometry requirements of UB2 and LB2M or LB2V may allow the lower beam light source(s) to remain activated when an upper beam light source is activated if the lower beam light source(s) contribute to upper beam photometric compliance.
(2) Lower beams may remain activated when upper beams are activated.
(3) Lower beams must remain activated when upper beams are activated.
(4) Beam contributor photometric allocation formula of S14.2.5.9 applies.
Table II-d-Headlighting Systems-Replaceable Bulb
| System designation | Light source composition | Photometry requirements reference | ||
| Table XVIII | Tables XIX-a, XIX-b, XIX-c | |||
| Upper beam mechanical and visual aim | Lower beam mech aim | Lower beam visual aim | ||
| 2 LAMP SYSTEM | ANY DUAL FILAMENT TYPE, OTHER THAN HB2, USED ALONE OR WITH ANOTHER DUAL FILAMENT TYPE OTHER THAN HB2 | UB2(1) OR UB3 | LB2M(1) OR LB3M | LB2V(1) OR LB3V |
| 2 LAMP SYSTEM | HB2 OR ANY SINGLE FILAMENT TYPE USED ALONE OR WITH ANY OTHER SINGLE OR DUAL FILAMENT TYPE | UB2(1) OR UB3 | LB2M(1) | LB2V(1) |
| 4 LAMP SYSTEM | ANY DUAL FILAMENT TYPE, OTHER THAN HB2, USED ALONE OR WITH ANOTHER DUAL FILAMENT TYPE OTHER THAN HB2 | UB1(2) OR UB3 | LB1M(2) OR LB3M | LB1V(2) OR LB3V |
| 4 LAMP SYSTEM | HB2 OR ANY SINGLE FILAMENT TYPE USED ALONE OR WITH ANY OTHER SINGLE OR DUAL FILAMENT TYPE. (U & L) | UB1(2) | LB1M(2) | LB1V(2) |
(1) Headlamps designed to conform to the photometry requirements of UB2 and LB2M or LB2V may allow the lower beam light source(s) to remain activated when an upper beam light source is activated if the lower beam light source(s) contribute to upper beam photometric compliance.
(2) Lower beams may remain activated when upper beams are activated.
Table III-Marking Requirements Location
| Lamp, reflective device, or other component | Marking | Marking location | Requirement |
| HEADLAMPS, BEAM CONTRIBUTORS, OR HEADLAMP REPLACEABLE LENS | |||
| "DOT" | Lens | S6.5.1 | |
| Optical axis marking | See requirement | S10.18.5 | |
| Manufacturer name and/or trademark | Lens | S6.5.3 | |
| Voltage | See requirement | S6.5.3 | |
| Part number or trade number | See requirement | S6.5.3 | |
| HEADLAMP REPLACEABLE LENS | Manufacturer identification | Lens | S6.5.3 |
| Headlamp identification | |||
| REPLACEABLE BULB HEADLAMPS | "U" or "L" (4 lamp system) | Lens | S10.15.4 |
| Replaceable bulb type | Lens | S6.5.3.4 | |
| SEALED BEAM HEADLAMPS | "sealed beam" | Lens | S6.5.3.3 |
| Type designation | See requirements | S6.5.3.3 | |
| INTEGRAL BEAM HEADLAMPS | "U" or "L" (4 lamp system) | Lens | S10.14.4 |
| MOTORCYCLE REPLACEABLE BULB HEADLAMPS | "motorcycle" | Lens | S10.17.2 |
| VISUALLY/OPTICALLY AIMED HEADLAMPS | "VOR" or "VOL" or "VO" | Lens | S10.18.9.6 |
| EXTERNALLY AIMED HEADLAMPS | Aim pad location & "H" or "V" | Lens | S10.18.7.1 |
| VEHICLE HEADLAMP AIMING DEVICES (VHAD) | Aiming scale(s) | See requirement | S10.18.8 |
| (HEADLAMP) REPLACEABLE LIGHT SOURCES | "DOT" | See requirement | S11.1 |
| Replaceable light source designation | See requirement | ||
| Manufacturer name and/or trademark | See requirement | ||
| REPLACEABLE LIGHT SOURCE BALLASTS | Manufacturer name or logo | See requirement | S11.2 |
| Part number | |||
| Light source identification | |||
| Rated laboratory life | |||
| High voltage warning | |||
| Output in watts and volts | |||
| "DOT" | |||
| LAMPS (OTHER THAN HEADLAMPS), REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT | "DOT" | See requirement | S6.5.1.2 |
| DAYTIME RUNNING LAMPS (DRL) | "DRL" | Lens | S6.5.2 |
| CONSPICUITY REFLEX REFLECTORS | "DOT-C" | Exposed surface | S8.2.2.1 |
| RETROREFLECTIVE SHEETING | "DOT-C2" or "DOT-C3" or "DOT-C4" | Exposed surface | S8.2.1.3 |
Table IV-a-Effective Projected Luminous Lens Area Requirements
| Lighting device | Passenger cars, multipurpose passenger vehicles, trucks, trailers, and buses of less than 2032 mm in overall width minimum effective projected luminous lens area (sq mm) | Multipurpose passenger vehicles, trucks, trailers, and buses 2032 mm or more in overall width minimum effective projected luminous lens area each lamp (sq mm) | Motorcycles minimum effective projected luminous lens area (sq mm) | |||
| Single compartment lamp | Multiple compartment lamp or multiple lamps | Multiple compartment lamp or multiple lamps | ||||
| Each compartment or lamp | Combined compartments or lamps | Each compartment or lamp | Single or combined compartments or lamps | |||
| Front turn signal lamp | 2200 | 2200 | 7500 | 2200 | 2258 | |
| Rear turn signal lamp | 5000 | 2200 | 5000 | 7500 | 2200 | 2258 |
| Stop lamp | 5000 | 2200 | 5000 | 7500 | 2200 | 1 5000 |
1 A motor driven cycle whose speed attainable in 1 mile is 30 mph or less may be equipped with a stop lamp whose minimum effective projected luminous lens area is not less than 2258 sq mm.
Table IV-b-Effective Projected Luminous Lens Area Requirements
| Lighting device | Passenger cars, multipurpose passenger vehicles, trucks, and buses of less than 2032 mm in overall width and with a GVWR of 10,000 lbs or less using a single lamp minimum effective projected luminous lens area (sq mm) | Multipurpose passenger vehicles, trucks, and buses of less than 2032 mm in overall width and with a GVWR of 10,000 lbs or less using dual lamps of identical size and shape minimum effective projected luminous lens area each lamp (sq mm) |
| High-mounted stop lamp | 2903 | 1452 |
Table IV-c-Effective Projected Luminous Lens Area Requirements
| Lighting device | School bus minimum effective projected luminous lens area each lamp (sq mm) |
| School bus signal lamp | 12,258 |
Table V-a-Visibility Requirements of Installed Lighting Devices
| Lighting device | Required visibility |
| Backup lamp | Lamps must be mounted so that the optical center of at least one lamp is visible from any eye point elevation from at least 1828 mm (6 ft) to 610 mm (2 ft) above the horizontal plane on which the vehicle is standing; and from any position in the area, rearward of a vertical plane perpendicular to the longitudinal axis of the vehicle, 914 mm (3 ft), to the rear of the vehicle and extending 914 mm (3 ft) beyond each side of the vehicle. |
| High-mounted stop lamp | Signal must be visible to the rear through a horizontal angle from 45° to the left to 45° to the right of the longitudinal axis of the vehicle. (Single lamp or two lamps together where required by S6.1.1.2 of this standard). |
| School bus signal lamp | Signal of front lamps to the front and rear lamps to the rear must be unobstructed within area bounded by 5° up to 10° down and 30° left to 30° right. |
Table V-b-Visibility Requirements of Installed Lighting Devices-Lens Area Visibility Option
| Lighting device | Corner points1 2 | Required visibility | |||
| Motorcycle | All other | ||||
| Turn signal lamp3 | 15° UP-20° IB | 15° UP-45° OB | 15° UP-45° IB | 15° UP-45° OB | Unobstructed minimum |
| 15° DOWN-20° IB | 15° DOWN-45° OB | 15° DOWN-45° IB | 15° DOWN-45° OB | effective projected | |
| Stop lamp | 15° UP-45° RIGHT4 | 15° UP-45° LEFT4 | 15° UP-45° IB | 15° UP-45° OB | luminous lens area |
| 15° DOWN-45° RIGHT4 | 15° DOWN-45° LEFT4 | 15° DOWN-45° IB | 15° DOWN-45° OB | of 1,250 sq mm in any | |
| Taillamp | 15° UP-45° RIGHT5 | 15° UP-45° LEFT5 | 15° UP-45° IB | 15° UP-45° OB | direction throughout |
| 15° DOWN-45° RIGHT5 | 15° DOWN-45° LEFT5 | 15° DOWN-45° IB | 15° DOWN-45° OB | the pattern defined by | |
| Parking lamp | No Requirement | No Requirement | 15° UP-45° IB | 15° UP-45° OB | the specified corner |
| No Requirement | No Requirement | 15° DOWN-45° IB | 15° DOWN-45° OB | points. | |
1 IB indicates an inboard direction (toward the vehicle's longitudinal centerline) and OB indicates an outboard direction.
2 Where a lamp is mounted with its axis of reference less than 750 mm above the road surface, the vertical test point angles located below the horizontal plane subject to visibility requirements may be reduced to 5° down.
3 Where more than one lamp or optical area is lighted at the front on each side of a multipurpose passenger vehicle, truck, trailer, or bus, of 2032 mm or more overall width, only one such area need comply.
4 If a multiple lamp arrangement is used for a motorcycle stop lamp, the inboard angle for each lamp shall be 10 degrees.
5 If a multiple lamp arrangement is used for a motorcycle tail lamp, the inboard angle for each lamp shall be 45 degrees.
Table V-c-Visibility Requirements of Installed Lighting Devices-Luminous Intensity Visibility Option
| Lighting device | Corner points1 2 | Required visibility Minimum luminous intensity in any direction throughout the pattern defined by the specified corner points. | |||
| Motorcycle | All Other | Candela | |||
| Turn signal lamp | 15° UP-20° IB | 15° UP-80° OB | 15° UP-45° IB | 15° UP-80° OB | 0.3 |
| 15° DOWN-20° IB | 15° DOWN-80° OB | 15° DOWN-45° IB | 15° DOWN-80° OB | ||
| Stop lamp | 15° UP-45° RIGHT4 | 15° UP-45° LEFT4 | 15° UP-45° IB | 15° UP-45° OB | 0.3 |
| 15° DOWN-45° RIGHT4 | 15° DOWN-45° LEFT4 | 15° DOWN-45° IB | 15° DOWN-45° OB | ||
| Taillamp3 | 15° UP-80° RIGHT5 | 15° UP-80° LEFT5 | 15° UP-45° IB | 15° UP-80° OB | 0.05 |
| 15° DOWN-80° RIGHT5 | 15° DOWN-80° LEFT5 | 15° DOWN-45° IB | 15° DOWN-80° OB | ||
| Parking lamp | No Requirement | No Requirement | 15° UP-45° IB | 15° UP-80° OB | 0.05 |
| No Requirement | No Requirement | 15° DOWN-45° IB | 15° DOWN-80° OB | ||
1 IB indicates an inboard direction (toward the vehicle's longitudinal centerline) and OB indicates an outboard direction.
2 Where a lamp is mounted with its axis of reference less than 750 mm above the road surface, the vertical test point angles located below the horizontal plane subject to visibility requirements may be reduced to 5° down
3 Inboard and outboard corner points are 80° for a single taillamp installed on a motorcycle
4 If a multiple lamp arrangement is used for a motorcycle stop lamp, the inboard angle for each lamp shall be 10 degrees.
5 If a multiple lamp arrangement is used for a motorcycle tail lamp, the inboard angle for each lamp shall be 45 degrees.
Table V-d-Visibility Requirements of Installed Lighting Devices (Legacy Visibility Alternative)
| Lighting device | Required visibility1 | |
| Turn signal lamp | All passenger cars, multipurpose passenger vehicles, trucks, buses, motorcycles, and trailers of less than 2032 mm overall width | Unobstructed minimum effective projected luminous lens area of 1250 sq mm through horizontal angle of H-V to H-45° OB. |
| All multipurpose passenger vehicles, trucks, buses, and trailers of 2032 mm or more overall width | Unobstructed minimum effective projected luminous lens area of 1300 sq mm through horizontal angle of H-V to H-45° OB. Where more than one lamp or optical area is lighted on each side of the vehicle, only one such area on each side need comply. | |
| Stop lamp | Unobstructed minimum effective projected luminous lens area of 1250 sq mm through horizontal angle of H-45° IB to H-45° OB. Where more than one lamp or optical area is lighted on each side of the vehicle, only one such area on each side need comply. | |
| Taillamp | Unobstructed minimum effective projected luminous lens area of 2 sq in through horizontal angle of H-45° IB to H-45° OB. Where more than one lamp or optical area is lighted on each side of the vehicle, only one such area on each side need comply. | |
1 IB indicates an inboard direction (toward the vehicle's longitudinal centerline) and OB indicates an outboard direction.
Table X-Side Marker Lamp Photometry Requirements
| Test point (degrees) | Minimum photometric intensity (cd)(2) red lamps | Minimum photometric intensity (cd)(2) amber lamps |
| 10U: | ||
| 45L(1) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(1) | 0.25 | 0.62 |
| H: | ||
| 45L(1) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(1) | 0.25 | 0.62 |
| 10D:(3) | ||
| 45L(1) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(1) | 0.25 | 0.62 |
(1) Where a side marker lamp installed on a motor vehicle less than 30 feet in overall length has the lateral angle nearest the other required side marker lamp on the same side of the vehicle reduced from 45° by design as specified by S7.4.13.2, the photometric intensity measurement may be met at the lesser angle.
(2) The photometric intensity values between test points must not be less than the lower specified minimum value of the two closest adjacent test points on a horizontal or vertical line.
(3) Where side marker lamps are mounted with their axis of reference less than 750 mm above the road surface, photometry requirements below 5° down may be met at 5° down rather than at the specified required downward angle.
Table XI-Clearance and Identification Lamps Photometry Requirements
| Test point (degrees) | Minimum photometric intensity (cd)(2) red lamps | Minimum photometric intensity (cd)(2) amber lamps |
| 10U: | ||
| 45L(4) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(4) | 0.25 | 0.62 |
| H: | ||
| 45L(4) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(4) | 0.25 | 0.62 |
| 10D:(1) | ||
| 45L(4) | 0.25 | 0.62 |
| V | 0.25 | 0.62 |
| 45R(4) | 0.25 | 0.62 |
| Maximum photometric intensity(3) (cd) red lamps | 15 |
(1) Where clearance lamps or identification lamps are mounted with their axis of reference less than 750mm above the road surface, photometry requirements below 5° down may be met at 5° down rather than at the specified required downward angle.
(2) The photometric intensity values between test points must not be less than the lower specified minimum value of the two closest adjacent test points on a horizontal or vertical line.
(3) When optically combined with a stop lamp or turn signal lamp, this maximum applies on or above the horizontal.
(4) Where clearance lamps are installed at locations other than on the front and rear due to the necessity to indicate the overall width of the vehicle, or for protection from damage during normal operation of the vehicle, they need not meet the photometric intensity requirement at any test point that is 45° inboard.
Table XVI-a-Reflex Reflector Photometry Requirements
| Observation angle (degrees) | Entrance angle (degrees) | Minimum performance | |||||
| Red reflectors | Amber reflectors | White reflectors | |||||
| (cd/incident ft-c) | (mcd/lux) | (cd/incident ft-c) | (mcd/lux) | (cd/incident ft-c) | (mcd/lux) | ||
| 0.2 | 0 | 4.5 | 420 | 11.25 | 1050 | 18 | 1680 |
| 10U | 3.0 | 280 | 7.5 | 700 | 12 | 1120 | |
| 10D(1) | 3.0 | 280 | 7.5 | 700 | 12 | 1120 | |
| 20L | 1.5 | 140 | 3.75 | 350 | 6 | 560 | |
| 20R | 1.5 | 140 | 3.75 | 350 | 6 | 560 | |
| 1.5 | 0 | 0.07 | 6 | 0.175 | 15 | 0.28 | 24 |
| 10U | 0.05 | 5 | 0.125 | 12.5 | 0.2 | 20 | |
| 10D(1) | 0.05 | 5 | 0.125 | 12.5 | 0.2 | 20 | |
| 20L | 0.03 | 3 | 0.075 | 7.5 | 0.12 | 12 | |
| 20R | 0.03 | 3 | 0.075 | 7.5 | 0.12 | 12 | |
(1) Where reflex reflectors are mounted with their axis of reference less than 750 mm above the road surface, photometry requirements below 5° down may be met at 5° down rather than at the required specified downward angle.
Table XVI-b-Additional Photometry Requirements for Conspicuity Reflex Reflectors
| Observation angle (degrees) | Entrance angle (degrees) | Minimum performance | ||
| Red (mcd/lux) | White horizontal orientation (mcd/lux) | White vertical orientation (mcd/lux) | ||
| 0.2 | 0 | 300 | 1250 | 1680 |
| 20L TO 20R | 560 | |||
| 30L TO 30R | 300 | 1250 | ||
| 45L TO 45R | 75 | 300 | ||
| 10U TO 10D | 1120 | |||
Table XVI-c-Retroreflective Sheeting Photometry Requirements
| Observation angle (degrees) | Entrance angle (degrees) | Minimum performance | |||||
| Grade dot-C2 | Grade dot-C3 | Grade dot-C4 | |||||
| White | Red | White | Red | White | Red | ||
| (cd/lux/sq m) | (cd/lux/sq m) | (cd/lux/sq m) | (cd/lux/sq m) | (cd/lux/sq m) | (cd/lux/sq m) | ||
| 0.2 | -4 | 250 | 60 | 165 | 40 | 125 | 30 |
| 30 | 250 | 60 | 165 | 40 | 125 | 30 | |
| 45 | 60 | 15 | 40 | 10 | 30 | 8 | |
| 0.5 | -4 | 65 | 15 | 43 | 10 | 33 | 8 |
| 30 | 65 | 15 | 43 | 10 | 33 | 8 | |
| 45 | 15 | 4 | 10 | 3 | 8 | 2 | |
Table XVII-School Bus Signal Lamp Photometry Requirements
| Test point (degrees) | Minimum photometric intensity (cd)(2) red lamps | Minimum photometric intensity (cd) amber lamps |
| 5U: | ||
| 20L | 150 | 375 |
| 10L | 300 | 750 |
| 5L | 300 | 750 |
| V | 300 | 750 |
| 5R | 300 | 750 |
| 10R | 300 | 750 |
| 20R | 150 | 375 |
| H: | ||
| 30L | 30 | 75 |
| 20L | 180 | 450 |
| 10L | 400 | 1000 |
| 5L | 500 | 1250 |
| V | 600 | 1500 |
| 5R | 500 | 1250 |
| 10R | 400 | 1000 |
| 20R | 180 | 450 |
| 30R | 30 | 75 |
| 5D: | ||
| 30L | 30 | 75 |
| 20L | 200 | 500 |
| 10L | 300 | 750 |
| 5L | 450 | 1125 |
| V | 450 | 1125 |
| 5R | 450 | 1125 |
| 10R | 300 | 750 |
| 20R | 200 | 500 |
| 30R | 30 | 75 |
| 10D:(1) | ||
| 5L | 40 | 100 |
| V | 40 | 100 |
| 5R | 40 | 100 |
(1) Where school bus signal lamps are mounted with their axis of reference less than 750 mm above the road surface, photometry requirements below 5° down may be met at 5° down rather than at the specified required downward angle.
(2) The photometric intensity values between test points must not be less than the lower specified minimum value of the two closest adjacent test points on a horizontal or vertical line.
Table XXI-Adaptive Driving Beam Photometry Requirements (1)
| Measurement distance interval (m) | Maximum illuminance Opposite direction (lux) | Maximum illuminance same direction (lux) |
| Greater than or equal to 15.0 and less than 30.0 | 3.1 | 18.9 |
| Greater than or equal to 30.0 and less than 60.0 | 1.8 | 18.9 |
| Greater than or equal to 60.0 and less than 120.0 | 0.6 | 4.0 |
| Greater than or equal to 120.0 and less than or equal to 220 | 0.3 | N/A |
(1) For purposes of determining conformance with these specifications, an observed value or a calculated value shall be rounded to the nearest 0.1 lux, in accordance with the rounding method of ASTM Practice E29 Using Significant Digits in Test Data to Determine Conformance with Specifications.
Table XXII-Adaptive Driving Beam System Test Matrix
| Scenario No. | Test vehicle speed (kph) | Orientation | Radius of curve (m.) | Curve direction | Superelevation (%) | Measurement distance range (m) |
| 1 | 96.6-112.7 [60-70 mph] | Opposite Direction | Straight | N/A | 0-2 | Greater than or equal to 15 and less than or equal to 220. |
| 2 | 40.2-48.3 [25-30 mph] | Opposite Direction | 85-115 | Left | 0-2 | Greater than or equal to 15 and less than 60. |
| 3 | 64.4-72.4 [40-45 mph] | Opposite Direction | 210-250 | Left | 0-2 | Greater than or equal to 15 and less than or equal to 150. |
| 4 | 80.5-88.5 [50-55 mph] | Opposite Direction | 335-400 | Left | 0-2 | Greater than or equal to 15 and less than or equal to 220. |
| 5 | 64.4-72.4 [40-45 mph] | Opposite Direction | 210-250 | Right | 0-2 | Greater than or equal to 15 and less than or equal to 50. |
| 6 | 80.5-88.5 [50-55 mph] | Opposite Direction | 335-400 | Right | 0-2 | Greater than or equal to 15 and less than or equal to 70. |
| 7 | 96.6-112.7 [60-70 mph] | Same Direction | Straight | N/A | 0-2 | Greater than or equal to 15 and less than or equal to 100. |
| 8 | 64.4-72.4 [40-45 mph] | Same Direction | 210-250 | Left | 0-2 | Greater than or equal to 15 and less than or equal to 100. |
49 C.F.R. §571.108