This article is devoted to study of isobar-Analogue states 1- in triplet A=14: 14C-14N-14O. Previously signs of neutron halo in the 1-, 6.09 MeV state of 14C were obtained by two independent groups. In this article we propose to study neighbouring nuclei 14N and 14O using the Modified diffraction model (MDM) method and the method of Asymptotic normalization coefficients (ANC). Methods were applied to experimental differential cross sections of 14C(α,α)14C scattering and reactions 13C(3He,d)14N and 14N(3He,t)14O. MDM and ANC gave practically similar within errors radii for the studied 1- states: The 6.09 MeV state in 14C-2.7 0.1 fm, the 8.06 MeV state in 14N-2.7 0.1 fm, the 5.17 MeV state in 14O-2.6 0.2 fm. Moreover, the signs of proton halo in the 1- state of 14N were obtained for the first time.