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Crewmember Demand Oxygen Mask

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Information about this document as published in the Federal Register.

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Federal Aviation Administration (FAA), DOT.


Notice of availability.


This notice announces the availability of Technical Standard Order (TSO) C-78a, Crewmember Demand Oxygen Mask. This TSO tells persons seeking a TSO authorization (TSOA) or letter of design approval (LODA) what minimum performance standards (MPS) their crewmember demand oxygen mask must meet to be identified with the appropriate TSO marking. This TSO has been revised to address a general requirement for oxygen masks to be supplied with an oxygen supply tube.


TSO-C78a will be available on or before June 13, 2008.

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Mr. John Petrakis, AIR-120, Room 815, Federal Aviation Administration, 800 Independence Avenue, SW., Washington, DC 20591. Telephone (202) 267-9274, fax (202) 267-5340, or e-mail at:

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TSO C-78a addresses crewmember demand oxygen masks and breathing valves that use either panel mounted or mask mounted demand and pressure-demand oxygen regulators.

This “a” revision to TSO-C78, became effective on February 13, 2008. Shortly after its release, we determined that the general requirement to provide an oxygen supply tube for Type II and Type IV oxygen masks needed to be revised. While an oxygen supply tube is a required component of the Type II and Type IV oxygen mask, the original TSO C-78 manufacturers are approved to provide oxygen supply tubes of different lengths. The lengths of those oxygen tubes provided by the manufacturer are aircraft specific. As is the case with all FAA approved TSO articles, which are only design and production approvals, the installation of a TSO C-78 or C-78a approved crewmember demand oxygen mask requires a separate installation approval. Therefore, to eliminate any confusion, we revised appendix 1 of TSO C-78a by removing changes we made to paragraph 3.9, Oxygen Supply Tube, regarding the length of the oxygen supply tube.

How to Obtain Copies

You can view or download TSO C-78a from its online location at: http://Start Printed Page​regulations_​policies/​orders_​notices/​. At this Web page, select Technical Standard Orders (TSO) Database. At the TSO page, select “Current.” For a paper copy, contact the person listed in For Further Information Contact. Note that referenced SAE International documents are copyrighted and may not be reproduced without the written consent of SAE International. You may purchase copies of SAE International documents from: SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, or directly from their Web site:​.

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Issued in Washington, DC, on May 7, 2008.

Susan J. M. Cabler,

Assistant Manager, Aircraft Engineering Division, Aircraft Certification Service.

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[FR Doc. E8-10555 Filed 5-13-08; 8:45 am]