When can an IAFDOF altitude be assigned?

An IAFDOF (Initial Approach Fix Departure On Flightpath) altitude can be assigned when traffic conditions prevent the safe operation of other altitudes. This is primarily a safety measure to ensure safe separation between aircraft while also managing airspace efficiently. In busy airspace, it is crucial for controllers to consider the positions and altitudes of surrounding traffic, thereby allowing an appropriate altitude that maintains separation.

While pilots may request specific altitudes or hold at certain levels, those requests must be evaluated against current traffic conditions. Additionally, even when there are no nearby aircraft, air traffic controllers need to consider other operational factors, such as airspace structure and procedures, before assigning an IAFDOF altitude. Therefore, the most prudent moment to assign this specific altitude is indeed when traffic conditions necessitate such a decision.