ETSO-C99a

• ED Decision 2016/013/R found in: CS-ETSO Amdt 17 - European Technical Standard Orders (Oct 2026)

#### ETSO-C99a *ED Decision 2016/013/R* ##### Flight Deck (Sedentary) Crew Member Protective Breathing Equipment **1 Applicability** This ETSO provides the requirements which Flight Deck (Sedentary) Crew Member Protective Breathing Equipment that are designed and manufactured on or after the date of this ETSO must meet in order to be identified with the applicable ETSO marking. **2 Procedures** 2.1 General Applicable procedures are detailed in CS-ETSO, [Subpart A](#_DxCrossRefBm920220672). 2.2 Specific None. **3 Technical Conditions** 3.1 Basic 3.1.1 Minimum Performance Standard Standards set forth in the SAE AS8031A, Personal Protective Devices for Toxic and Irritating Atmospheres Air Transport Flight Deck (Sedentary) Crew members, dated 3/1/1999 as amended by [Appendix 1](#_DxCrossRefBm920220799) to this ETSO. 3.1.2 Environmental Standard To be tested in accordance with the procedures in SAE AS8026A, Crewmember Demand Oxygen Mask for Transport Category Aircraft, dated July 1996, paragraph 4.5. 3.1.3 Computer Software None. 3.1.4 Electronic Hardware Qualification None. 3.2 Specific None. 3.2.1 Failure Condition Classification See CS-ETSO, Subpart A, paragraph 2.4. **4 Marking** 4.1 General Marking as detailed in CS-ETSO, Subpart A, paragraph 1.2. 4.2 Specific In addition to 4.1, the mask assembly shall be marked with the following: (1) Size (if more than one size is manufactured), (2) Type (as specified in [ETSO-C89a](#_DxCrossRefBm920220790), paragraph 3), and (3) ‘Beards will not seal’, if applicable. **5 Availability of Referenced Document** See CS-ETSO, Subpart A, paragraph 3. [Amdt ETSO/11]