Large efforts have been made by the volcano observatories and institutions responsible for data collection and evaluation. Thus data presented here can be used on the condition that these organisations and people are given proper credit for their work, following normal practice in scientific communication: (1) If data from this repository constitutes an important part of the work, co-authorship should be offered to the listed contributors and the data-set should be cited. (2) If data from this repository constitutes only a small, but still important part of the work, this data-set should be cited. To cite this data-set include the following information: "Chigna, G., Arellano, S., Caceres, V., Sanchez, E., Galle, B., SO2 flux of -SANTIAGUITO- volcano from the NOVAC data-base, 2020, [Data set] , v.001, doi:10.17196/novac.santiaguito.001." Additional data, data with higher time resolution and raw data may be made available upon request to the network coordinator: -bo.galle@chalmers.se and the responsible person at the respective ovservatory: -gustavo.chigna@gmail.com. This data-set has license: CC-BY 4.0.