49 CFR § 552.12 - Definitions.

---
identifier: "/us/cfr/t49/s552.12"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "49 CFR § 552.12 - Definitions."
title_number: 49
title_name: "Transportation"
section_number: "552.12"
section_name: "Definitions."
chapter_name: "NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION"
part_number: "552"
part_name: "PETITIONS FOR RULEMAKING, DEFECT, AND NONCOMPLIANCE ORDERS"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "49 U.S.C. 30111, 30118, 30162; delegation of authority at 49 CFR 1.50."
regulatory_source: "40 FR 42014, Sept. 10, 1975, unless otherwise noted."
cfr_part: "552"
---


# 552.12 Definitions.

For purposes of this subpart, the following definitions apply:

(a) *Dynamic automatic suppression system (DASS)* means a portion of an air bag system that automatically controls whether or not the air bag deploys during a crash by:

(1) Sensing the location of an occupant, moving or still, in relation to the air bag;

(2) Interpreting the occupant characteristics and location information to determine whether or not the air bag should deploy; and

(3) Activating or suppressing the air bag system based on the interpretation of characteristics and occupant location information.

(b) *Automatic suppression zone (ASZ)* means a three-dimensional zone adjacent to the air bag cover, specified by the vehicle manufacturer, where air bag deployment will be suppressed by the DASS if a vehicle occupant enters the zone under specified conditions.

(c) *Standard No. 208* means 49 CFR 571.208.