---
kind: "section"
citation: "49 C.F.R. § 572.176"
title: "49"
number: "572.176"
heading: "Knees and knee impact test procedure."
url: "https://uscodex.org/cfr/49/572.176"
---

# §572.176. Knees and knee impact test procedure.

- (a) The knee assembly for the purpose of this test is the part of the leg assembly shown in drawing 420-5000 (incorporated by reference, see [§ 572.170](/cfr/49/572.170.md)).
- (b) When the knee assembly, consisting of lower upper leg assembly (420-5200), femur load transducer (SA572-S10, included in drawing 420-0000) or its structural replacement (420-5121), lower leg assembly (420-5300), ankle assembly (420-5400), and foot molded assembly (420-5500) (all incorporated by reference, see [§ 572.170](/cfr/49/572.170.md)) is tested according to the test procedure in [subsection (c)](#c) of this section:
  - (1) The peak resistance force as measured with the test probe-mounted accelerometer must not be less than 2.6 kN (585 lbf) and not more than 3.2 kN (719 lbf).
  - (2) The force shall be calculated by the product of the impactor mass and its deceleration.
- (c) **Test Procedure.** The test procedure for the knee assembly is as follows:
  - (1) Soak the knee assembly in a controlled environment at any temperature between 20.6 and 22.2 °C (69 and 72 °F) and a relative humidity between 10 and 70 percent for at least four hours prior to a test.
  - (2) **Mount the test material and secure it to a rigid test fixture as shown in Figure T6.** No part of the foot or tibia may contact any exterior surface.
  - (3) Align the test probe so that throughout its stroke and at contact with the knee it is within 2 degrees of horizontal and collinear with the longitudinal centerline of the femur.
  - (4) Guide the pendulum so that there is no significant lateral, vertical, or rotational movement at the time of initial contact between the impactor and the knee.
  - (5) The test probe velocity at the time of contact shall be 2.1 ±0.03 m/s (6.9 ±0.1 ft/s).
  - (6) No suspension hardware, suspension cables, or any other attachments to the probe, including the velocity vane, shall make contact with the dummy during the test.

## Notes

### Source

Source: 77 FR 11667, Feb. 27, 2012, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 322, 30111, 30115, 30117 and 30166; delegation of authority at 49 CFR 1.95