Aaron as High Priest and as one of those that offered incense Numbers 16:17, could not be defiled by going among the dead.
The censers were not to be used again for censers, nor the coals on them for kindling the incense to be offered before the Lord. Yet neither of them could fittingly be employed for common purposes. The censers therefore were beaten into plates for the altar; the coals were scattered at a distance.