Safety Areas
Runway Safety Area (RSA)
Temporary Threshold
This section describes the various safety areas associated with airfield operations and their application to paving projects. While it does not cover all defined areas, it discusses the three most commonly encountered ones in airport paving: the runway safety area, taxiway safety area and temporary runway thresholds.
Runway Safety Area (RSA)
A runway safety area (see Image) is the surface surrounding the runway that is maintained so that an aircraft that overshoots/undershoots or strays from the runway will suffer a reduced risk of damage. As such it should be free of objects including construction equipment. In general, no construction can occur within 200 ft from a runway centerline unless that runway is closed. If construction is closer, the only way to keep the runway open is to restrict aircraft operation on it to smaller aircraft that need smaller RSAs. For instance, resurfacing a taxiway that leads up to a runway will likely involve working in the runway’s RSA and within 200 ft of the runway centerline. This will require that either the runway be shut down or restricted in aircraft operations. FAA Advisory Circular 150/5300-13 AIRPORT DESIGN defines RSAs and their dimensions.
Taxiway Safety Areas (TSA)
Similar to a RSA, a taxiway safety area is the surface surrounding a taxiway that is maintained so that an aircraft that strays from the taxiway will suffer a reduced risk of damage. It should also be free of objects including construction equipment. As with RSAs, adjacent work may encroach on TSAs and require additional taxiway closures. FAA Advisory Circular 150/5300-13 AIRPORT DESIGN defines TSAs and their dimensions.
Temporary Runway Threshold
Sometimes runway paving or repairs can be accomplished on the ends of runways without shutting down the entire runway. In these cases a temporary runway threshold is established, which essentially declares a portion of the runway closed while keeping the rest open for full or partial use. To do this, a temporary runway threshold is established, which is essentially a temporary end to the runway. FAA Advisory Circular 150/5370-2E OPERATIONAL SAFETY ON AIRPORTS DURING CONSTRUCTION describes appropriate markings, signs and procedures associated with temporary runway thresholds.
Sometimes temporary thresholds can be used to reduce the amount of time a runway needs to be closed for work (e.g., resurfacing). For instance, a temporary runway threshold can be established in order to resurface the end of a runway (see Image). Once this resurfacing is complete, another temporary runway threshold can be established to resurface the other end of the runway. Once this is complete, the entire runway can be fully closed to resurface the middle of the runway. By using the temporary runway thresholds, the required full closure time can be reduced.
