EN 4529-003:2026

• Abstract:

  This document specifies the required characteristics of sealing plugs, class T, for use in elements of electrical and optical connection containing cable (wire) sealing grommets, according to EN 4529-002. It is used together with EN 4529-001.

• Status: Not Published
• Publication Date: 01-Sep-2026
• ICS: 49.060 - Aerospace electric equipment and systems
• ICS: 49.090 - On-board equipment and instruments
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 2/S 3 - Elements of Connection (Connectors, Contacts, rear accessories, crimping tools
• Current Stage: 5060 - Closure of Vote - Formal Approval
• Start Date: 02-Jul-2026
• Completion Date: 02-Jul-2026
• Ref Project: kSIST FprEN 4529-003:2026 - Aerospace series - Elements of electrical and optical connection - Sealing plugs - Part 003: Class T - Product standard

• Revises: EN 4529-003:2006 - Aerospace series - Elements of electrical and optical connection - Sealing plugs - Part 003: Class T - Product standard
• Effective Date: 02-Oct-2024

Overview

EN 4529-003:2026, developed by CEN, is a product standard for sealing plugs, class T, used in aerospace series electrical and optical connection elements. This document defines the required characteristics of these sealing plugs, which are designed for use with cable (wire) sealing grommets as specified in EN 4529-002, and must be referenced together with EN 4529-001 for technical specifications.

Sealing plugs as defined in this standard are critical for maintaining integrity and environmental protection within aerospace connectors, particularly in systems where electrical and optical connections must be reliably sealed against contaminants, temperature extremes, and other harsh conditions.

Key Topics

• Scope and Application
  EN 4529-003 specifies the design, materials, dimensions, and performance of class T sealing plugs for aerospace connectors. These plugs support high reliability in environments where electrical and optical connections require secure sealing from fluids, dust, and temperature fluctuations.

• Performance and Materials

  • Class T sealing plugs are suitable for operating temperatures from -65 °C to +260 °C.
  • Plugs are manufactured from polytetrafluoroethylene (PTFE), ensuring robust chemical resistance, durability, and high-temperature performance.

• Types and Sizing

  • Multiple size codes (e.g., 22, 20, 16, 12, 10, 8, 4, 0) are defined to accommodate diverse connector cavities.
  • Each size and style (Normal and Long) features specific dimensional and color-coding requirements for easy identification and correct installation.

• Testing and Compliance
  Sealing plugs must meet stringent performance tests including:

  • Visual and dimensional checks
  • Insulation resistance
  • Endurance at elevated and low temperatures
  • Resistance to fluids and mold
  • Flammability and hydrolytic stability

Applications

EN 4529-003:2026 is widely applied in the aerospace industry, where electrical and optical connectors are exposed to challenging operational environments, such as:

• Aircraft wiring systems: Protects sensitive connector interfaces in commercial, military, and cargo aircraft.
• Avionic and control systems: Maintains system reliability by preventing moisture, dust, and chemical ingress into critical electronic modules.
• Satellite and space vehicle connections: Ensures long-term endurance under extreme temperature fluctuations and vacuum conditions.
• Maintenance and upgrade operations: Used for sealing unused ports or retrofitting existing connector assemblies with enhanced environmental protection.

The specification of color codes, dimensional uniformity, and use of premium materials all contribute to rapid identification, consistent installation, and dependable operation, supporting compliance with rigorous aerospace quality management requirements.

Related Standards

• EN 4529-001: Aerospace series - Elements of electrical and optical connection - Sealing plugs - Part 001: Technical specification. This standard provides detailed technical requirements for products covered in EN 4529-003.
• EN 4529-002: Aerospace series - Elements of electrical and optical connection - Sealing plugs - Part 002: Index of product standards.
• EN 2591 series: Test methods for electrical and optical connection elements, covering visual inspection, dimensional verification, insulation resistance, temperature endurance, and more.
• EN ISO 13000-2: Plastics - PTFE semi-finished products - Preparation of test specimens and determination of properties.
• EN 2997-001 and EN 3155-001: Additional technical specifications for aerospace connectors and electrical contacts.
• MS27488: U.S. military standard for sealing plugs, serving as an initial basis for plug design.

This network of standards ensures that aerospace electrical and optical connectors, and their sealing solutions, meet stringent safety, reliability, and performance criteria for demanding applications.

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Keywords: EN 4529-003:2026, aerospace electrical connectors, sealing plugs standard, class T sealing plugs, PTFE aerospace plugs, electrical grommet sealing, CEN aerospace standards, environmental sealing for optical connections, aerospace connector protection.

SLOVENSKI STANDARD
oSIST prEN 4529-003:2025
01-julij-2025
Aeronavtika - Elementi električnih in optičnih povezav - Tesnilni čepi - 003. del:
Razred T - Standard za proizvod
Aerospace series - Elements of electrical and optical connection - Sealing plugs - Part
003: Class T - Product standard
Luft- und Raumfahrt - Elektrische und optische Verbindungselemente - Verschluss-
Stopfen - Teil 003: Klasse T - Produktnorm
Série aérospatiale - Organes de connexion électrique et optique - Obturateurs
d’étanchéité - Partie 003 : Classe T - Norme de produit
Ta slovenski standard je istoveten z: prEN 4529-003
ICS:
49.060 Letalska in vesoljska Aerospace electric
električna oprema in sistemi equipment and systems
oSIST prEN 4529-003:2025 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 4529-003:2025
oSIST prEN 4529-003:2025
DRAFT
EUROPEAN STANDARD
prEN 4529-003
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2025
ICS 49.060 Will supersede EN 4529-003:2006
English Version
Aerospace series - Elements of electrical and optical
connection - Sealing plugs - Part 003: Class T - Product
standard
Série aérospatiale - Organes de connexion électrique et Luft- und Raumfahrt - Elektrische und optische
optique - Obturateurs d'étanchéité - Partie 003 : Classe Verbindungselemente - Verschluss-Stopfen - Teil 003:
T - Norme de produit Klasse T - Produktnorm
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 4529-003:2025 E
worldwide for CEN national Members.

oSIST prEN 4529-003:2025
prEN 4529-003:2025 (E)
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Required characteristics . 6
4.1 Specific characteristics . 6
4.2 Dimensions – Mass, colours . 6
4.3 Material . 6
4.4 Dimensions and mass . 6
4.5 Tests . 9
5 Designation . 9
6 Marking . 10
7 Technical specification . 10
Annex A (informative) Standard evolution form . 11
Bibliography . 12

oSIST prEN 4529-003:2025
prEN 4529-003:2025 (E)
European foreword
This document (prEN 4529-003:2025) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 4529-003:2006.
This document includes the following significant technical changes with respect to EN 4529-003:2006:
— Introduction of sealing plugs size code 10.
— The main changes between this edition and the previous edition are listed in Table A.1.
oSIST prEN 4529-003:2025
prEN 4529-003:2025 (E)
Introduction
The sealing plug specified in this document is derived from MS27488.
oSIST prEN 4529-003:2025
p
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