(a) The thorax consists of the upper torso assembly in drawing 78051-89, revision K and shall conform to each of the drawings subtended therein.

(b) When impacted by a test probe conforming to § 572.36(a) at 22 fps ±0.40 fps in accordance with paragraph (c) of this section, the thorax of a complete dummy assembly (78051-218, revision U, without shoes, shall resist with a force of 1242.5 pounds ±82.5 pounds measured by the test probe and shall have a sternum displacement measured relative to spine of 2.68 inches ±0.18 inches. The internal hysteresis in each impact shall be more than 69% but less than 85%. The force measured is the product of pendulum mass and deceleration.

(c) Test procedure. (1) Soak the test dummy in an environment with a relative humidity from 10% to 70% until the temperature of the ribs of the test dummy have stabilized at a temperature between 69 degrees F and 72 degrees F.

(2) Seat the dummy without back and arm supports on a surface as shown in Figure 23, and set the angle of the pelvic bone at 13 degrees plus or minus 2 degrees, using the procedure described in S11.4.3.2 of Standard No. 208 ( § 571.208 of this chapter ).

(3) Place the longitudinal centerline of the test probe so that it is .5 ±.04 in. below the horizontal centerline of the No. 3 Rib (reference drawing number 79051-64, revision A-M) as shown in Figure 23.

(4) Align the test probe specified in § 572.36(a) so that at impact its longitudinal centerline coincides within .5 degree of a horizontal line in the dummy's midsagittal plane.

(5) Impact the thorax with the test probe so that the longitudinal centerline of the test probe falls within 2 degrees of a horizontal line in the dummy midsagittal plane at the moment of impact.