A washing apparatus for a 3D-printed article is provided for the removal of support material from the article. The apparatus includes a glove isolation cabinet with a liquid-discharging nozzle to enable an operator to spray an article with a washing liquid, and a drain. A first filter arrangement receives liquid discharged from the cabinet. The washing liquid drains through the first filter arrangement under the influence of gravity but the first filter arrangement is located in a trough in which washing liquid that has passed through the first filter arrangement accumulates whereby, in use, one or more filters of the first filter arrangement are submerged to ensure filtered-out residue remains submerged in the washing liquid. A pump is provided to pump liquid that has passed through the first filter arrangement through a second filter arrangement adapted to filter out solid material equal to or greater than 5 μm in size.
