---
title: "CS ADR-DSN.H.445 Obstacle-free zone (OFZ) — Certification Specifications and Guidance Material for Aerodrome Design (CS-ADR-DSN) — Issue 7, Aerodromes · Avioverse"
description: "An OFZ is intended to protect aeroplanes from fixed and mobile obstacles during Category II and III operations when approaches are continued below…"
url: "https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-h-obstacle-limitation-surfaces/cs-adr-dsn-h-445"
---

# CS ADR-DSN.H.445 Obstacle-free zone (OFZ)

Certification Specifications and Guidance Material for Aerodrome Design (CS-ADR-DSN) — Issue 7 · Regulation (EU) No 139/2014 · EAR revision 13 Mar 2026

IR Implementing rule

## CS ADR-DSN.H.445 Obstacle-free zone (OFZ)

(a) An OFZ is intended to protect aeroplanes from fixed and mobile obstacles during Category II and III operations when approaches are continued below decision height, and during any subsequent missed approach or [balked landing](https://avioverse.aero/glossary/easa/balked-landing) with all engines operating normally. It is not intended to supplant the requirement of other surfaces or areas where these are more demanding.

(b) The OFZ is made up of the following [obstacle](https://avioverse.aero/glossary/easa/obstacle) limitation surfaces:

(1) inner approach surface;

(2) inner transitional surfaces; and

(3) balked landing surface.

\[Issue: ADR-DSN/3]

IR · CS ADR-DSN.H.445 — Regulation (EU) No 139/2014 · ED Decision 2016/027/R · Aerodromes Easy Access Rules · EAR revision 13 Mar 2026

[All rules in CHAPTER H — OBSTACLE LIMITATION SURFACES](https://avioverse.aero/regulations/easa/aerodromes/cs-adr-dsn/chapter-h-obstacle-limitation-surfaces)

Consolidated from the EASA Easy Access Rules (revision 13 Mar 2026, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.