Abstract: A steam box for applying steam to a moving web comprising a housing having a leading end and a trailing end positionable above and proximate to a moving web; a supply header within the housing, said supply header in communication with a steam source; at least first and second steam chambers aligned with said leading edge in the direction of movement of said web, said first and second steam chambers able to receive steam from the said supply header to apply steam through respective first and second steam discharge points to the moving web, and a screen plate securable to said housing, said screen plate including a horizontal plate; and a first descending barrier positioned between said first and second steam discharge points, said descending barrier having a first trailing side adjacent to said-second steam discharge point to protect said second steam discharge point from stock flung from the web.