i've seen people playing with selenium toner like it was water and
artists eating their lunch with cadmium paint all over their hands.
i guess it's up to you...
ventilation is probably the more important issue as hypo is caustic
to the lungs (as are most photo-related chemicals). if your stove
has a vent hood work off of it (with your plywood on top of it
and next to the sink it can work well...make _sure_ burners are
off!). with an open window and the vent going you might get an
adequate exchange of air. ....but, the kitchen is really not
the place.
best to use the bathroom with plywood over the tub and the bath
vent on with a fan reversed out a window or door and another
fan bringing fresh air in....
don't eat the stuff, wear gloves, wash hands after and spend
a lot of effort on good VENTILATION, i.e., exchanges of air