A bone marrow access apparatus includes a bone penetrating member having an internal channel having an opening at a proximal end and an opening at a distal end, and a valve cap engaged with the bone penetrating member. The valve cap defines an interior cavity in which part of the bone penetrating member is situated to thereby secure the valve cap to the bone penetrating member. The valve cap includes a valve having an opening having an open state in which the channel is not obstructed and a closed state preventing flow of material through the channel. By being repeatedly switchable between the open and closed states, the valve controls access to the channel by bone marrow sampling and biopsy instruments.
