Agency: Centro de Informação e Vigilância Sismovulcânica dos Açores (CIVISA)
Name: Escala de Alertas para a Aviação (ICAO) [Aviation Alert Scale (ICAO)]
Note: this scheme follows the standard ICAO aviation VAL scheme.
The terrestrial VAL scheme can be found here.
Elements of VAL system
| Domain | Aviation |
| Volcano | All |
| Scheme range | 4-level scale |
| Lowest level | 1 |
| Highest level | 4 |
| Level name type | Color |
| Level for lack/loss of monitoring | No |
| Volcanic activity | Yes |
| Hazards possible | Yes |
| Locations affected | No |
| Potential impacts | No |
| Forecast language | Yes |
| Timing language | Yes |
| Actions to take | No |
| Agency actions | No |
| Link to evacuations | No |
| Reporting frequency per level | No |
| Link to monitoring thresholds | No |
| Step-up and step-down language | Yes |