[en] PVT relations in liquid and solid T₂ near the melting curve were measured over 20.5 K--22.1 K and 0 MPa--7 MPa (0 bar--70 bar) with a cell that used diaphragms for pressure and volume variation and measurement. Because of ortho-para self conversion, the melting pressure Pm and the liquid molar volume V_im increased with time. The rates were consistent with a second order reaction similar to that for c the J = odd concentration: dc/dt = -k₁c² + k₂c(1-c), where k₁ = 6 - 9 x 10^-2h^-1. By extrapolation, the ortho and para forms differed by ΔP_m ∼ 6 bar and ΔV_im ∼ 0.5%. Measurements of the volume change on melting and the thermal expansion and compressibility for liquid T₂ were consistent with those for H₂ and D₂. Impurities such as H₂, HT, DT, and ³He were removed by a technique using an adsorption column of cold activated alumina. Correction for ³He growth during an experiment were adequate except near the triple point