For a vertically moving door operator, a secondary entrapment protection device supplied with, or as an accessory to, an operator shall consist of:

An external photoelectric sensor that when activated results in an operator that is closing a door to reverse direction of the door, returns the door to, and stops the door at the fully open position, and the sensor prevents an operator from closing an open door,

An external edge sensor installed on the edge of the door that, when activated as tested per § 1211.12(a)(4)(1) results in an operator that is closing a door to reverse direction of the door, returns the door to, and stops the door at the fully open position, and the sensor prevents an operator from closing an open door,

An inherent door sensor independent of the system used to comply with § 1211.7 that, when activated, results in an operator that is closing a door to reverse direction of the door and the sensor prevents an operator from closing an open door, or

Any other external or internal device that provides entrapment protection equivalent to paragraph (a)(1)(i), (ii), or (iii) of this section.

The door operator is not required to return the door to, and stop the door at, the fully open position when an inherent entrapment circuit senses an obstruction during the opening travel.

The door operator is not required to return the door to, and stop the door at, the fully open position when a control is actuated to stop the door during the opening travel—but the door cannot be moved towards the closing direction until the operator has reversed the door a minimum of 2 inches (50.8 mm).

For horizontal sliding garage door operators, a secondary entrapment protection device supplied with, or as an accessory to, an operator shall consist of:

An external photoelectric sensor that, when activated, results in an operator that is closing or opening a door to reverse direction of the door for a minimum of 2 inches (50.8 mm); or

An external edge sensor installed on the edge of the door that, when activated as tested per § 1211.12 (a)(4)(2), results in an operator that is closing or opening a door to reverse direction of the door for a minimum of 2 inches (50.8 mm).

With respect to paragraphs (a) and (b) of this section, the operator shall monitor for the presence and correct operation of the device at least once during each close cycle. Should the device not be present or a fault condition occurs which precludes the sensing of an obstruction, including an interruption of the wireless signal to the wireless device or an open or short circuit in the wiring that connects an external entrapment protection device to the operator and device's supply source, the operator shall be constructed such that:

For a vertically moving door, the closing door shall open and an open door shall not close more than 1 foot (305 mm) below the upmost position;

For a horizontally sliding door, the door shall not move in the opening or closing direction; or

The operator shall function as required by § 1211.6(b)(1).

An external entrapment protection device or system, when employing a wireless control, shall comply with paragraph (e) of this section when installed at its farthest distance from the operator as recommended in the installation instructions.

An external entrapment protection device shall comply with the applicable requirements in §§ 1211.10, 1211.11, and 1211.12.

An inherent secondary entrapment protection device described in § 1211.6(b)(3) shall comply with the applicable requirements in § 1211.13. Software used in an inherent entrapment protection device shall comply with UL 1998 (incorporated by reference, see § 1211.40).