---
title: "ETSO-C103 — CS-ETSO · Avioverse"
description: "Continuous Flow Oxygen Mask Assembly (for Non-transport Category Aircraft) 1 Applicability This ETSO gives the requirements which continuous flow…"
url: "https://avioverse.aero/regulations/easa/cs-etso/subpart-b/etso-c103"
---

# ETSO-C103

European Technical Standard Orders (CS-ETSO) · CS-ETSO · EAR revision 1 Oct 2026

IR Implementing rule

## ETSO-C103

Continuous Flow Oxygen Mask Assembly (for Non-transport Category Aircraft)

1 Applicability

This ETSO gives the requirements which continuous flow aviation oxygen masks that are 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

Procedures are detailed in CS-ETSO Subpart A.

2.2 Specific

None.

3 Technical Conditions

3.1 Basic

3.1.1 Minimum Performance Standard

Standards set forth in the Society of Automotive Engineers, Inc., (SAE) Aerospace Standard (AS) 1224A „Continuous Flow Aviation Oxygen Masks„ dated September 15, 1971, revised January 15, 1978, as amended and supplemented by this ETSO:

Exception. Masks defined as open-port or restrictive-dilution masks without rebreathing or reservoir bag as defined by Aerospace Standard AS 1224A, paragraph 1.4(d) are not eligible for approval under this ETSO.

3.1.2 Environmental Standard

As per Aerospace Standard AS 1224A, paragraph 3.4.1.

3.1.3 Computer Software

None

3.2 Specific

None.

4 Marking

4.1 General

Marking is detailed in CS-ETSO Subpart A paragraph 1.2.

4.2 Specific

None.

5 Availability of Referenced Document

See CS-ETSO Subpart A paragraph 3.

IR · ETSO-C103 — CS-ETSO · ED Decision 2003/10/RM · CS-ETSO Easy Access Rules · EAR revision 1 Oct 2026

[All rules in SUBPART B – LIST OF ETSOs](https://avioverse.aero/regulations/easa/cs-etso/subpart-b)

Consolidated from the EASA Easy Access Rules (revision 1 Oct 2026, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.