Safety glazing standards

The Decision Tree has been developed to assist you in identifying the appropriate glass to use based on HUMAN IMPACT SAFETY GLAZING NZS 4223.3:2016 effective from 30 May 2017.

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This guide must be used in conjunction with NZS 4223.3:2016. Do not rely on this decision tree (NZS 4223) alone as this is not a full representation of the standard.

NZS 4223.3 applies to glazing wholly or partly within 2000 mm of the floor or ground level that is not protected from human impact.

Where required, manifestation is required between 800 mm and 1200 mm – refer clause 2.2. Manifestation is not required for housing.

Each pane of safety glass shall be legibly and permanently marked. Refer clause 2.8.

Where there is likely to be human impact on both sides of a unit, both panes of the IGU shall comply with NZS 4223.3

Where there is only likely to be human impact on one side of a unit, only the pane on that side shall apply.

Where glazing safeguards a fall of 1000 mm or more, human impact is unlikely to occur on the outer pane of an IGU. The outer pane is normally designed for wind loading.

Annealed glass may be used for the middle pane of a triple IGU, subject to wind load requirements.

Balustrades, fences and screens are not covered by this guide. Refer section 22 Barriers.

Check all external glazing for NZS 4223.4 wind load requirements. Thicker glass may be required.

The following are excluded from NZS 4223.3:2016:

  • Glazing in lift cars and liftwells
  • Furniture glass, cabinet glass, vanities, glass basins, refrigeration units, internal glass fitments, glass wall linings, framed internal wall mirrors and mirrors not specifically covered.
  • Buildings and structures with public access intended for non-inhabitable building structures for horticulture or agricultural use.
  • Restoration or repairs to existing decorated glass Glazing that might fail due to stresses other than tensile stresses, such as glass floors
  • Plastic glazing materials
  • Construction and installation of windows
  • Glass blocks, pavers, slumped, formed or cast glass
  • Point-fixed or point-supported systems, used for glazing, cladding, signage, and the like, not specifically covered.



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