{"id":"F2006B02848","name":"AD/B737/146 - Oxygen Masks","slug":"ad-b737-146-oxygen-masks","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42190,"registerId":"commonwealth-F2006B02848-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.","sortOrder":0},{"sectionNumber":"AD/B737/146 Oxygen Masks 10/2000","sectionType":"part","heading":"AD/B737/146 Oxygen Masks 10/2000","content":"# AD/B737/146 Oxygen Masks 10/2000\n\nApplicability: Model 737 series aeroplanes with line numbers 1 through 2984 inclusive.\n\nRequirement: 1. Unless previously accomplished, perform a general visual inspection to determine the vendor of all oxygen masks in the passenger cabin in accordance with Boeing Service Bulletin (SB) 737-35-1049, including Appendix A, dated 17 September 1998. If the oxygen mask is not manufactured by Puritan-Bennett, no further action is required by this Directive for that mask.\n\nNote 1: For the purposes of this Directive, a general visual inspection is defined as: \"A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.\"\n\n    2. If the oxygen mask is manufactured by Puritan-Bennett, or if the manufacturer of the mask cannot be identified, perform a general visual inspection to determine the manufacturing date of the oxygen mask, in accordance with the applicable service bulletin. For each oxygen mask manufactured by Puritan-Bennett, or an unidentified manufacturer, if the mask was manufactured between May 1986 and July 1998 inclusive or if the manufacturing date cannot be determined accomplish either of the following:\n\n    Replace the lanyards on the masks with new lanyards in accordance with SB 737-35-1049, including Appendix A.\n\n    b. Replace the existing oxygen mask with a new mask that was manufactured by Puritan-Bennett before May 1986 or after July 1998, or by another vendor, and that has the same Boeing part number, or that is approved by the United States Federal Aviation Administration (FAA) for installation as an alternative to the Puritan-Bennett mask.\n\n    3. No person shall install an oxygen mask manufactured by Puritan-Bennett between May 1986 and July 1998 inclusive, on any aeroplane, unless the lanyard has been replaced with a new lanyard in accordance with Requirement 2. B of this Directive.","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive sets an explicit, self‑contained scope: Boeing 737s line numbers 1–2984 and masks of a specific vendor/date range (Applicability; Requirements 1–3). It does not expand applicability beyond those aircraft or introduce additional categories of equipment; it prescribes inspection and remedial measures within that stated scope."},"complexity_factors":["Narrow applicability but precise scope: Model 737, line numbers 1–2984 (Applicability).","Two-stage inspection requirement: identify vendor, then determine manufacturing date if vendor is Puritan‑Bennett or unknown (Requirement 1 and 2).","Date‑range trigger: remedial action required only for masks manufactured between May 1986 and July 1998 inclusive, or when date cannot be determined (Requirement 2).","Two alternative remedies: replace lanyards or replace masks with specified acceptable parts (Requirement 2a–b).","Absolute installation prohibition for affected Puritan‑Bennett masks unless lanyard replaced (Requirement 3).","Mandated compliance with Boeing Service Bulletin SB 737‑35‑1049 (including Appendix A) for inspection and corrective action (Requirement text).","Definition of 'general visual inspection' that may require access tools and could increase practical labour/time (Note 1).","Dependence on FAA approval for alternative masks introduces an external regulatory dependency (Requirement 2b).","Operational burden concentrated on aircraft operators and maintenance providers who must inspect many masks and track serial/date information."],"plain_english_summary":"This Airworthiness Directive requires operators of Boeing 737 aircraft (line numbers 1–2984) to inspect all passenger‑cabin oxygen masks to identify the vendor and manufacturing date, and to either replace mask lanyards or replace masks that fall into a specified Puritan‑Bennett date range. It addresses an unsafe condition tied to Puritan‑Bennett masks made between May 1986 and July 1998 and forbids installing those masks unless the lanyards have been replaced."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope: addressing a specific safety defect in oxygen masks on specific Boeing 737 aircraft. It has not expanded beyond this technical safety correction."},"complexity_factors":["Multiple conditional branches: checks for manufacturer, date ranges, and identification status","Cross-reference to external Boeing Service Bulletin (SB 737-35-1049) for technical procedures","Nested date range logic (May 1986–July 1998 inclusive)","Defined term embedded in note ('general visual inspection')","Alternative compliance paths (replace lanyard OR replace entire mask with specific alternatives)"],"plain_english_summary":"This safety order addresses faulty lanyards on Puritan-Bennett passenger oxygen masks installed in older Boeing 737s (serials 1–2984). Operators must identify affected masks made May 1986–July 1998 and either replace the lanyard or the entire mask, and may not install those original masks unless the lanyard has been replaced. It affects airlines, maintenance crews, and passenger emergency safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-146-oxygen-masks","history":"/api/acts/ad-b737-146-oxygen-masks/history","analysis":"/api/acts/ad-b737-146-oxygen-masks/analysis","conflicts":"/api/acts/ad-b737-146-oxygen-masks/conflicts","importantCases":"/api/acts/ad-b737-146-oxygen-masks/important-cases","documents":"/api/acts/ad-b737-146-oxygen-masks/documents"}}