A new glass in the fluoroarsenate family was fabricated and doped with Er3+ ions. The compositions made are (Na4As2O7)40 (BaF2)30 (YF3)x with xequals 0, 0.1, 0.5, 1, 3, and 5. The optical properties of Er3+ ions were established in terms of absorption and emission spectra, Judd-Ofelt calculations, and lifetime measurements in the visible and infrared domains. Because of the presence of arsenic, these glasses show lower phonon energies than their fluorophosphate counterparts. As a result, the green emission from the 4S3/2 level of Er3+ can be observed. At concentration of 0.1 mol $ ErF3, the experimental lifetime for 4S3/2 is well accounted for by thermalization processes and the occurrence of multiphonon relaxations. For the 4I11/2 and 4I13/2 levels, the lifetime is maximum for 1% erbium concentration, due to the occurrence of signal self-absorption. Excellent agreement is obtained between the radiative and experimental lifetimes of the 4I13/2 level, which validates the application of the Judd-Ofelt theory.