IEC 61753-111-08:2021

Overview - IEC 61753-111-08:2021 (Sealed closures for category G – Ground)

IEC 61753-111-08:2021 is an IEC performance standard that specifies the minimum tests, test severities and measurement requirements for sealed fibre optic closures classified as category G (Ground). It defines how a sealed closure must perform under mechanical, environmental and optical stress to be declared conformant. Free-breathing closures are excluded. This edition (2021) is a technical revision that replaces the 2009 edition and updates terminology and test severities to align with IEC 61753-1:2018 and IEC 61756-1:2019.

Key topics and technical requirements

The standard focuses on practical, measurable verification of sealed closure performance. Key technical topics include:

• Sealing and pressure tests
  • Sealing tests performed with 20 kPa overpressure
  • Pass/fail criterion for pressure loss added to mechanical sealing tests
• Mechanical resilience
  • Vibration sealing test: 10 Hz, 3 mm amplitude, 1,000,000 cycles
  • Crush resistance: 1 000 N for 10 minutes added
  • Cable retention, axial compression: reduced loads for small-diameter cables/tubes
  • Torsion and bending tests: cycle duration specified
  • Assembly/disassembly test: duration reduced to 5 cycles
  • Free-fall test removed (covered by optical shock test)
• Chemical and contamination resistance
  • Immersion in diesel (1 h) with 24 h drying; petroleum jelly immersion for 5 days
  • Resistance to stress-cracking solvents for 5 days
• Environmental exposure
  • Water immersion: 1 m for 7 days (added)
  • Temperature cycling: reduced to 12 cycles
• Optical and visual performance
  • Optical loss and visual inspection pass/fail criteria defined for tested samples

Practical applications and users

Who uses IEC 61753-111-08:

• Manufacturers of sealed fibre optic closures (design verification and product classification)
• Test laboratories performing standardized performance tests
• Telecom operators and utilities specifying closures for ground-level and buried applications
• Procurement and quality assurance teams writing tender specifications and acceptance criteria
• Certification bodies assessing claims of compliance

Benefits:

• Ensures consistent minimum performance for field-deployed sealed closures
• Provides objective pass/fail criteria for sealing, mechanical, chemical and optical tests
• Helps reduce deployment risk for ground-level fiber infrastructure

Related standards

• IEC 61753-1:2018 (general test severities and definitions)
• IEC 61756-1:2019 (relevant terminology updates)
• IEC 61300 series (basic test and measurement procedures: vibration, shock, retention, torsion)
• IEC 60793-2-50, IEC 60068-2-10 (referenced fibre and environmental tests)
• IEC 62005 (guidance on reliability testing)

Keywords: IEC 61753-111-08, sealed closures, category G, ground, fibre optic closures, sealing tests, cable retention, vibration test, water immersion, crush resistance, optical performance.