Antifoam particles contain: porous copolymers of urea or melamine or a mixture thereof with an alkanal, and a silicone antifoam composition which is liquid at 0\xb0 C. The computer system determines that a health risk condition exists within an area based on the obtained data. The mounting hinge is pivotable such that the power distribution unit can be pivoted to an extended position to facilitate removal of removable modules mounted within the electronic system.