Significato e scopo
4.1 The procedures described in this specification are intended to assist in the evaluation of coating performance on a variety of metal panels, including new or rusted steel.

4.2 A causa delle differenze nella radiazione solare, wet time, temperatura, contaminanti, e altri fattori, the relative durability of paint during outdoor exposure may vary considerably depending on the location of the exposure. Perciò, it cannot be assumed that the results of a single exposure at a single location will help determine the relative durability of different locations. Exposure is recommended at multiple sites with different climates that represent a wide range of expected service conditions.

4.2.1 Due to annual climate variability, the results of a single exposure test cannot be used to predict the absolute rate of material degradation. It takes several years of repeated exposure to obtain an “average” test result for a given location.

4.2.2 Solar radiation varies greatly with the time of year. This can lead to large differences in apparent degradation rates for many polymers. It is not recommended to compare results for materials exposed for a short period of time (less than one year) unless the materials were exposed at the same location at the same time.

4.3 Meaning and Use of G7 in practice addresses many of the variables that need to be considered in external exposure testing. Guide G141 provides more information on variability in aging tests.

ASTM D 1014-2018 “Test di esposizione all'aperto per vernici e rivestimenti minacciosi su substrati metallici”

Ambito di applicazione
1.1 This practice covers the procedures to be followed when exposing external paints and coatings directly to metal surfaces. When the sponsor actual exposure of the aging test is carried out by a separate agency, the specific conditions for testing and controlling the exposure of the specimen should be clearly defined and mutually agreed upon by the parties.

1.2 Experience has shown that the metal used as a test substrate has a significant impact on weathering results. The aim of this practice is to define specific steel and other metal surfaces for testing in order to minimize this source of variability.

1.3 I valori espressi in unità SI sono considerati standard. I valori indicati tra parentesi sono solo di riferimento.

1.4 Questo standard non è destinato ad affrontare tutti i problemi di sicurezza, se presente, legati al suo utilizzo. È responsabilità dell'utente di questo standard stabilire la sicurezza adeguata, pratiche sanitarie e ambientali e per determinare l'applicabilità delle restrizioni normative prima dell'uso.

1.5 La presente norma internazionale è stata sviluppata in conformità con i principi di standardizzazione riconosciuti a livello internazionale stabiliti nella Decisione sui principi per lo sviluppo di norme internazionali, Linee guida e raccomandazioni emesse dal Comitato sugli ostacoli tecnici al commercio dell'Organizzazione mondiale del commercio.