The pair, aged 19 and 35, were working at the Range premises on Parry Lane when a suspected gas leak caused the blast shortly after 4.35pm.
Chief Insp Suzanne Akeroyd, of Bradford police, said emergency services found the women trapped but uninjured. They were led to safety and treated for shock at the scene.
She added: “Search and rescue dogs were deployed to the scene, as well as a structural engineer to assess the stability of the building.
“A total of 40 people were led to safety from adjoining premises.
“The cause of the explosion is still being investigated, but is not believed to be suspicious at this stage.”
Roads were expected to remain closed overnight as firefighters stayed at the scene.