571.201—Standard No. 201; Occupant protection in interior impact.

S1. Purpose and scope. This standard specifies requirements to afford impact protection for occupants.
S2. Application. This standard applies to passenger cars and to multipurpose passenger vehicles, trucks, and buses with a GVWR of 4,536 kilograms or less, except that the requirements of S6 do not apply to buses with a GVWR of more than 3,860 kilograms.
S3. Definitions.
A-pillar means any pillar that is entirely forward of a transverse vertical plane passing through the seating reference point of the driver's seat.
Ambulance means a motor vehicle designed exclusively for the purpose of emergency medical care, as evidenced by the presence of a passenger compartment to accommodate emergency medical personnel, one or more patients on litters or cots, and equipment and supplies for emergency care at a location or during transport.
B-pillar means the forwardmost pillar on each side of the vehicle that is, in whole or in part, rearward of a transverse vertical plane passing through the seating reference point of the driver's seat, unless:
Brace means a fixed diagonal structural member in an open body vehicle that is used to brace the roll-bar and that connects the roll-bar to the main body of the vehicle structure.
Convertible means a vehicle whose A-pillars are not joined with the B-pillars (or rearmost pillars) by a fixed, rigid structural member.
Convertible roof frame means the frame of a convertible roof.
Convertible roof linkage mechanism means any anchorage, fastener, or device necessary to deploy a convertible roof frame.
Daylight opening means, for openings on the side of the vehicle, other than a door opening, the locus of all points where a horizontal line, perpendicular to the vehicle longitudinal centerline, is tangent to the periphery of the opening. For openings on the front and rear of the vehicle, other than a door opening, daylight opening means the locus of all points where a horizontal line, parallel to the vehicle longitudinal centerline, is tangent to the periphery of the opening. If the horizontal line is tangent to the periphery at more than one point at any location, the most inboard point is used to determine the daylight opening.
Door frame means the rearmost perimeter structure, including trim but excluding glass, of the forward door and the forwardmost perimeter structure, including trim but excluding glass, of the rear door of a pair of adjacent side doors that:
Door opening means, for door openings on the side of the vehicle, the locus of all points where a horizontal line, perpendicular to the vehicle longitudinal centerline, is tangent to the periphery of the side door opening. For door openings on the back end of the vehicle, door opening means the locus of all points where a horizontal line, parallel to the vehicle longitudinal centerline, is tangent to the periphery of the back door opening. If the horizontal line is tangent to the periphery at more than one point at any location, the most inboard point is the door opening.
Dynamically deployed upper interior head protection system means a protective device or devices which are integrated into a vehicle and which, when activated by an impact, provide, through means requiring no action from occupants, protection against head impacts with upper interior structures and components of the vehicle in crashes.
Forehead impact zone means the part of the free motion headform surface area that is determined in accordance with the procedure set forth in S8.10.
Interior rear quarter panel means a vehicle interior component located between the rear edge of the side door frame, the front edge of the rearmost seat back, and the daylight opening.
Mid-sagittal plane of a dummy means a longitudinal vertical plane passing through the seating reference point of a designated seating position.
Other door frame means the rearmost perimeter structure, including trim but excluding glass, of the forward door and the forwardmost perimeter structure, including trim but excluding glass, of the rear door of a pair of adjacent side doors that:
Other pillar means any pillar which is not an A-pillar, a B-pillar, or a rearmost pillar.
Pillar means any structure, excluding glazing and the vertical portion of door window frames, but including accompanying moldings, attached components such as safety belt anchorages and coat hooks, which:
Roll-bar means a fixed overhead structural member, including its vertical support structure, that extends from the left to the right side of the passenger compartment of any open body vehicles and convertibles. It does not include a header.
Seat belt anchorage means any component involved in transferring seat belt loads to the vehicle structure, including, but not limited to, the attachment hardware, but excluding webbing or straps, seat frames, seat pedestals, and the vehicle structure itself, whose failure causes separation of the belt from the vehicle structure.
Seat belt mounting structure means:
(a) A vehicle body or frame component, including trim, that incorporates an upper seat belt anchorage conforming to the requirements of S4.2.1 and S4.3.2 of 49 CFR 571.210, that is located rearward of the rearmost outboard designated seating position, and that extends above a horizontal plane 660 mm above the seating reference point (SgRP) of that seating position; and
(b) A vehicle body or frame component, including trim, that incorporates an upper seat belt anchorage conforming to the requirements of S4.2.1 and S4.3.2 of 49 CFR 571.210, that is located forward of the rearmost outboard designated seating position, and that extends above a horizontal plane 460 mm above the SgRP of that seating position located rearward of the anchorage.
Sliding door track means a track structure along the upper edge of a side door opening that secures the door in the closed position and guides the door when moving to and from the open position.
Stiffener means a fixed overhead structural member that connects one roll-bar to another roll-bar or to a header of any open body vehicle or convertible.
Upper roof means the area of the vehicle interior that is determined in accordance with the procedure set forth in S8.15.
Windshield trim means molding of any material between the windshield glazing and the exterior roof surface, including material that covers a part of either the windshield glazing or exterior roof surface.
S4Requirements
S4.1Except as provided in S4.2, each vehicle shall comply with either:
S4.2Vehicles manufactured on or after September 1, 1998 shall comply with the requirements of S5 and S6.
S5Requirements for instrument panels, seat backs, interior compartment doors, sun visors, and armrests. Each vehicle shall comply with the requirements specified in S5.1 through S5.5.2.
S5.1Instrument panels. Except as provided in S5.1.1, when that area of the instrument panel that is within the head impact area is impacted in accordance with S5.1.2 by a 6.8 kilogram, 165 mm diameter head form at—
(b) A relative velocity of 19 kilometers per hour for vehicles that meet the occupant crash protection requirements of S5.1 of 49 CFR 571.208 by means of inflatable restraint systems and meet the requirements of S4.1.5.1(a)(3) by means of a Type 2 seat belt assembly at the right front designated seating position, the deceleration of the head form shall not exceed 80 g continuously for more than 3 milliseconds.
S5.1.1The requirements of S5.1 do not apply to:
S5.1.2Demonstration procedures. Tests shall be performed as described in Society of Automotive Engineers Recommended Practice J921, “Instrument Panel Laboratory Impact Test Procedure,” June 1965, using the specified instrumentation or instrumentation that meets the performance requirements specified in Society of Automotive Engineers Recommended Practice J977, “Instrumentation for Laboratory Impact Tests,” November 1966, except that:
S5.2Seat Backs. Except as provided in S5.2.1, when that area of the seat back that is within the head impact area is impacted in accordance with S5.2.2 by a 6.8 kilogram, 165 mm diameter head form at a relative velocity of 24 kilometers per hour, the deceleration of the head form shall not exceed 80g continuously for more than 3 milliseconds.
S5.2.2Demonstration procedures. Tests shall be performed as described in Society of Automotive Engineers Recommended Practice J921, “Instrument Panel Laboratory Impact Test Procedure,” June 1965, using the specified instrumentation or instrumentation that meets the performance requirements specified in Society of Automotive Engineers Recommended Practice J977, “Instrumentation for Laboratory Impact Tests,” November 1966, except that:
S5.3Interior compartment doors. Each interior compartment door assembly located in an instrument panel, console assembly, seat back, or side panel adjacent to a designated seating position shall remain closed when tested in accordance with either S5.3.1(a) and S5.3.1(b) or S5.3.1(a) and S5.3.1(c). Additionally, any interior compartment door located in an instrument panel or seat back shall remain closed when the instrument panel or seat back is tested in accordance with S5.1 and S5.2. All interior compartment door assemblies with a locking device must be tested with the locking device in an unlocked position.
S5.3.1Demonstration procedures.
S5.4Sun visors.
S5.4.1A sun visor that is constructed of or covered with energy-absorbing material shall be provided for each front outboard designated seating position.
S5.4.2Each sun visor mounting shall present no rigid material edge radius of less than 3.2 mm that is statically contactable by a spherical 165 mm diameter head form.
S5.5Armrests.
S5.5.1General. Each installed armrest shall conform to at least one of the following:
S5.5.2Folding armrests. Each armrest that folds into the seat back or between two seat backs shall either:
S6Requirements for upper interior components.
S6.1Vehicles manufactured on or after September 1, 1998. Except as provided in S6.3 and S6.1.4, for vehicles manufactured on or after September 1, 1998 and before September 1, 2002, a percentage of the manufacturer's production, as specified in S6.1.1, S6.1.2, or S6.1.3 shall conform, at the manufacturer's option, to either S6.1(a) or S6.1(b). For vehicles manufactured by final stage manufacturers on or after September 1, 1998 and before September 1, 2006, a percentage of the manufacturer's production as specified in S6.1.4 shall, except as provided in S6.3, conform, to either S6.1(a) or S6.1(b). The manufacturer shall select the option by the time it certifies the vehicle and may not thereafter select a different option for the vehicle.
(3) Each vehicle shall, when equipped with a dummy test device specified in Part 572, subpart M, and tested as specified in S8.16 through S8.28, comply with the requirements specified in S7 when crashed into a fixed, rigid pole of 254 mm in diameter, at any velocity between 24 kilometers per hour (15 mph) and 29 kilometers per hour (18 mph).
S6.1.1Phase-in Schedule #1
S6.1.1.1Vehicles manufactured on or after September 1, 1998 and before September 1, 1999. Subject to S6.1.5(a), for vehicles manufactured by a manufacturer on or after September 1, 1998 and before September 1, 1999, the amount of vehicles complying with S7 shall be not less than 10 percent of:
S6.1.1.2Vehicles manufactured on or after September 1, 1999 and before September 1, 2000. Subject to S6.1.5(b), for vehicles manufactured by a manufacturer on or after September 1, 1999 and before September 1, 2000, the amount of vehicles complying with S7 shall be not less than 25 percent of:
S6.1.1.3Vehicles manufactured on or after September 1, 2000 and before September 1, 2001. Subject to S6.1.5(c), for vehicles manufactured by a manufacturer on or after September 1, 2000 and before September 1, 2001, the amount of vehicles complying with S7 shall be not less than 40 percent of:
S6.1.1.4Vehicles manufactured on or after September 1, 2001 and before September 1, 2002. Subject to S6.1.5(d), for vehicles manufactured by a manufacturer on or after September 1, 2001 and before September 1, 2002, the amount of vehicles complying with S7 shall be not less than 70 percent of:
S6.1.2Phase-in Schedule #2
S6.1.2.1Vehicles manufactured on or after September 1, 1998 and before September 1, 1999. Subject to S6.1.5(a), for vehicles manufactured by a manufacturer on or after September 1, 1998 and before September 1, 1999, the amount of vehicles complying with S7 shall be not less than seven percent of:
S6.1.2.2Vehicles manufactured on or after September 1, 1999 and before September 1, 2000. Subject to S6.1.5(b), for vehicles manufactured by a manufacturer on or after September 1, 1999 and before September 1, 2000, the amount of vehicles complying with S7 shall be not less than 31 percent of:
S6.1.2.3Vehicles manufactured on or after September 1, 2000 and before September 1, 2001. Subject to S6.1.5(c), for vehicles manufactured by a manufacturer on or after September 1, 2000 and before September 1, 2001, the amount of vehicles complying with S7 shall be not less than 40 percent of:
S6.1.2.4Vehicles manufactured on or after September 1, 2001 and before September 1, 2002. Subject to S6.1.5(d), for vehicles manufactured by a manufacturer on or after September 1, 2001 and before September 1, 2002, the amount of vehicles complying with S7 shall be not less than 70 percent of:
S6.1.3Phase-in Schedule #3
S6.1.3.1Vehicles manufactured on or after September 1, 1998 and before September 1, 1999 are not required to comply with the requirements specified in S7.
S6.1.3.2Vehicles manufactured on or after September 1, 1999 shall comply with the requirements specified in S7.
S6.1.4Phase-in Schedule #4 A final stage manufacturer or alterer may, at its option, comply with the requirements set forth in S6.1.4.1 and S6.1.4.2.
S6.1.4.1Vehicles manufactured on or after September 1, 1998 and before September 1, 2009 are not required to comply with the requirements specified in S7.
S6.1.4.2Vehicles manufactured on or after September 1, 2009 shall comply with the requirements specified in S7.
S6.1.5Calculation of complying vehicles.
S6.1.6Vehicles produced by more than one manufacturer.
S6.1.6.1For the purpose of calculating average annual production of vehicles for each manufacturer and the number of vehicles manufactured by each manufacturer under S6.1.1 through S6.1.4, a vehicle produced by more than one manufacturer shall be attributed to a single manufacturer as follows, subject to S6.1.6.2.
S6.2Vehicles manufactured on or after September 1, 2002 and vehicles built in two or more stages manufactured after September 1, 2006. Except as provided in S6.1.4 and S6.3, vehicles manufactured on or after September 1, 2002 shall, when tested under the conditions of S8, conform, at the manufacturer's option, to either S6.2(a) or S6.2(b). Vehicles manufactured by final stage manufacturers on or after September 1, 2006 shall, except as provided in S6.3, when tested under the conditions of S8, conform, at the manufacturer's option, to either S6.2(a) or S6.2(b). The manufacturer shall select the option by the time it certifies the vehicle and may not thereafter select a different option for the vehicle.
(3) Except as provided in S6.2(b)(4), each vehicle shall, when equipped with a dummy test device specified in 49 CFR part 572, subpart M, and tested as specified in S8.16 through S8.28, comply with the requirements specified in S7 when crashed into a fixed, rigid pole of 254 mm in diameter, at any velocity between 24 kilometers per hour (15 mph) and 29 kilometers per hour (18 mph).
(4) Vehicles certified as complying with the vehicle-to-pole requirements of S9 of 49 CFR 571.214, Side Impact Protection, need not comply with the pole test requirements specified in S6.2(b)(3) of this section.
S6.3A vehicle need not meet the requirements of S6.1 through S6.2 for:
S7Performance Criterion. The HIC(d) shall not exceed 1000 when calculated in accordance with the following formula:

Code of Federal Regulations

[Please see PDF for image: ER04AU98.002 ]

Code of Federal Regulations

Where the term a is the resultant head acceleration expressed as a multiple of g (the acceleration of gravity), and t1 and t2 are any two points in time during the impact which are separated by not more than a 36 millisecond time interval.
(b) For the part 572, subpart M, anthropomorphic test dummy; HIC(d)=HIC.
S8Target location and test conditions. The vehicle shall be tested and the targets specified in S10 located under the following conditions.
S8.1Vehicle test attitude.
S8.2Windows and Sunroofs.
S8.3Convertible tops. The top, if any, of convertibles and open-body type vehicles is in the closed passenger compartment configuration.
S8.4Doors.
S8.5Sun visors. Each sun visor shall be placed in any position where one side of the visor is in contact with the vehicle interior surface (windshield, side rail, front header, roof, etc.).
S8.6Steering wheel and seats.
S8.7Seat belt anchorages. If a target is on a seat belt anchorage, and if the seat belt anchorage is adjustable, tests are conducted with the anchorage adjusted to a point midway between the two extreme adjustment positions. If the anchorage has distinct adjustment positions, none of which is midway between the two extreme positions, tests are conducted with the anchorage adjusted to the nearest position above the midpoint of the two extreme positions.
S8.8Temperature and humidity.
S8.10Forehead impact zone. The forehead impact zone of the headform is determined according to the procedure specified in (a) through (f).
S8.11Target circle. The area of the vehicle to be impacted by the headform is marked with a solid circle 12.7 mm in diameter, centered on the targets specified in S10, using any transferable opaque coloring medium.
S8.12Location of head center of gravity.
S8.13Impact configuration.
S8.13.1The headform is launched from any location inside the vehicle which meets the conditions of S8.13.4. At the time of launch, the midsagittal plane of the headform is vertical and the headform is upright.
S8.13.2The headform travels freely through the air, along a velocity vector that is perpendicular to the headform's skull cap plate, not less than 25 mm before making any contact with the vehicle.
S8.13.3At the time of initial contact between the headform and the vehicle interior surface, some portion of the forehead impact zone of the headform must contact some portion of the target circle.
S8.13.4 Approach angles. The headfo