A hinge assembly (110, 225) for a toilet seat, the hinge assembly (110, 225) comprising: a hinge post for pivotally supporting the toilet seat on a toilet bowl; a bolt connectable to the hinge post for securing the hinge post to the toilet bowl, the bolt being configured to extend through an opening in the toilet bowl; a nut (135, 435, 535) threadable onto the bolt about an axis to secure the hinge post to the toilet bowl, the nut (135, 435, 535) having a first segment threadable onto the bolt, a second segment coaxial along the axis with the first segment, and a shear segment coaxial along the axis with and connecting the first and second segments (270, 275), the shear segment having a lower torque resistance than the first and second segments (270, 275) such that the shear segment breaks when the nut (135, 435, 535) is rotated relative to the hinge post and torque applied to the second segment reaches a predetermined amount; and a washer (260, 460, 565) configured to surround the bolt between the nut (135, 435, 535) and the toilet bowl, the washer (260, 460, 565) being made of a low friction material; wherein the first segment, the second segment, and the shear segment of the nut (135, 435, 535) are formed as a single piece; wherein the first segment includes an outer surface having a similar shape and size as an outer surface of the second segment such that both the first and second segments (270, 275) are configured to be engaged by a tool; and wherein the nut (135, 435, 535) includes a neck segment extending from the first segment in the direction opposite the second segment, the neck segment including a projection (300, 305) allowing the washer (260, 460, 565) to be snap-assembled around the neck segment. a hinge post for pivotally supporting the toilet seat on a toilet bowl; a bolt connectable to the hinge post for securing the hinge post to the toilet bowl, the bolt being configured to extend through an opening in the toilet bowl; a nut (135, 435, 535) threadable onto the bolt about an axis to secure the hinge post to the toilet bowl, the nut (135, 435, 535) having a first segment threadable onto the bolt, a second segment coaxial along the axis with the first segment, and a shear segment coaxial along the axis with and connecting the first and second segments (270, 275), the shear segment having a lower torque resistance than the first and second segments (270, 275) such that the shear segment breaks when the nut (135, 435, 535) is rotated relative to the hinge post and torque applied to the second segment reaches a predetermined amount; and a washer (260, 460, 565) configured to surround the bolt between the nut (135, 435, 535) and the toilet bowl, the washer (260, 460, 565) being made of a low friction material; wherein the first segment, the second segment, and the shear segment of the nut (135, 435, 535) are formed as a single piece; wherein the first segment includes an outer surface having a similar shape and size as an outer surface of the second segment such that both the first and second segments (270, 275) are configured to be engaged by a tool; and wherein the nut (135, 435, 535) includes a neck segment extending from the first segment in the direction opposite the second segment, the neck segment including a projection (300, 305) allowing the washer (260, 460, 565) to be snap-assembled around the neck segment.