TGSI compliance audits in Sydney: independent tactile indicator checks before handover
Tactile ground surface indicators (TGSIs) are one of the most frequent defect items at occupation certificate. Setback is wrong, the depth is short, the contrast fails, or the indicators are missing at a hazard the Part D4 table requires. An independent TGSI compliance audit checks the installed indicators against AS 1428.4.1 as called up by the NCC before the certifier walks the site. NSW building work is assessed under NCC 2022 Amendment 2 until 1 May 2027. The Premises Standards reference AS 1428.1:2021 from 29 July 2025.
TGSI compliance audits in one paragraph
A TGSI compliance audit is a site inspection of installed tactile ground surface indicators against the requirements of AS 1428.4.1 and the NCC Volume One Part D4 families that call them up. It covers warning indicators at stairs, ramps, landings and other hazards, and directional indicators where required for wayfinding. The audit records setback, depth, luminance contrast and layout so the access report can status-code each location. Sydney Access Consultants carries out the audit as part of a design review or a pre-handover inspection. We do not supply or install the indicators.
What the standards require
AS 1428.4.1 sets the design and installation requirements for TGSIs. The NCC Part D4 provisions call up the Standard for locations where tactile indicators are required on an accessible path. Key families checked in an audit include:
- Warning TGSIs at the top of stairs, at ramps steeper than a stated gradient, and at other specified hazards.
- Setback from the hazard edge (the distance is taken from the Standard; no invented figures appear in the report).
- Depth of the indicator strip.
- Luminance contrast against the adjacent floor surface.
- Directional TGSIs where the path of travel needs to be indicated.
- Layout around landings, doorways and changes in direction.
Always verify the current clause wording and figures in AS 1428.4.1 and the applicable NCC edition before accepting a layout.
Common failures found at audit
- Warning indicators placed too close to or too far from the stair nosing or ramp transition.
- Strip depth shorter than the Standard requires.
- Insufficient luminance contrast so the indicators are not detectable by foot or cane.
- Missing indicators at a secondary stair or ramp that forms part of an accessible path.
- Indicators interrupted by floor joints, grates or changes in material.
- Directional indicators that do not align with the actual path of travel.
What the access report records
Each TGSI location is status-coded: compliant, capable of compliance, non-compliant, insufficient information, or Performance Solution. Photographs and measured setbacks support the status. Where an existing building or heritage fabric prevents a full deemed-to-satisfy installation, the route is documented as a Performance Solution. See Performance Solutions.
When to commission a TGSI audit
Best timing is after the indicators are installed but before occupation-certificate inspection, so defects can be corrected without delaying handover. The audit can also form part of a development-application or construction-certificate design review on the drawings. For broader access reporting see disability access reports for DA and CC.
Related pages
Frequently asked questions
What is a TGSI compliance audit?
An independent site check of installed tactile ground surface indicators against AS 1428.4.1 and the NCC Part D4 requirements that call the Standard up.
Do all buildings need TGSIs?
Warning and directional indicators are required where the Part D4 provisions and AS 1428.4.1 call for them on an accessible path. Confirm the locations on each project.
Can the audit be done from drawings only?
A design review can check the proposed layout. Final compliance is confirmed on site after installation.
What if the indicators cannot meet the Standard?
Document a Performance Solution with evidence. Do not claim compliance where the installation fails the deemed-to-satisfy criteria.
Call (02) 9586 3111 to book a TGSI audit or access report.