Detent position hinge for use with containment systems

A containment system including:

• a. An upwardly opening door having a horizontal rotation axis;
• b. A hinge attachment region adjacent to said horizontal rotation axis;
• and
• c. At least one detent hinge connecting said door to said hinge attachment region, said detent hinge including an outside assembly leaf and a center assembly leaf, wherein said outside assembly leaf and said center assembly leaf form a first detent angle and a second detent angle therebetween, and wherein said at least one detent hinge includes an outside hinge assembly including at least one outside knuckle defining a radially concave cam divot;
• a center hinge assembly including at least one center knuckle engaged with said outside hinge, said center knuckle defining an elongated first engagement portion and an elongated second engagement portion, said first and second engagement portions positioned end-to-end in a non-collinear orientation thereby defining at least one cam locking notch having an internal obtuse angle where said first and second engagement portions adjoin;
• and exactly one cam positionable between said cam divot and said cam locking notch traversing one end of said center knuckle, wherein said detent hinge is in a locked position when said cam is simultaneously engaged with said cam divot and said cam locking notch.

A method of accessing a chamber of a containment system including the steps of:

• a. Depressing a plunger of a detent hinge to push exactly one locking cam from its resting position into a radially concave cam divot;
• b. Raising the free edge an upwardly opening door along a horizontal rotation axis;
• c. Releasing pressure on the plunger to return the locking cam to its resting position;
• d. Allowing the locking cam to engage with a cam locking notch to secure the door in an open position, wherein said cam locking notch defines a first engagement portion and a second engagement portion positioned end-to-end in a non-collinear orientation thereby defining a cam locking notch having an internal obtuse angle where said first and second engagement portions adjoin;
• and
• e. Restricting access to the chamber by depressing the plunger, lowering the free edge of the door, releasing pressure on the plunger and allowing the cam to engage with the cam locking notch to secure the door in a closed position.