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(a) Type and Location.
(1) Spring or Oil Buffers.
Buffers of the spring or oil type shall be installed under the cars and counterweights of personnel hoists.
NOTE: Section 1604.5(b)(1) requires buffers under all cars and counterweights in hoistways which are above accessible spaces.
Spring buffers or their equivalent may be used where the rated speed is not in excess of 300 feet per minute.
EXCEPTION: For rated speeds of 301 to 600 feet per minute, spring buffers having a stroke of not less than 12 inches may be used provided a terminal speed limiting device conforming to the requirements given under Section 1604.23(d) is provided.
Buffers shall be located symmetrically with reference to the vertical center line of the car frame or the counterweight frame within a tolerance of 2 inches.
(b) Construction and Requirements for Spring Buffers.
(1) Buffer Stroke.
The stroke of the buffer spring, as marked on its marking plate, shall be equal to, or greater than, the following:
Rated Car Speed Stroke (feet per minute) (inches) 100 or less 1 1/2 101 to 150 2 1/2 151 to 200 4 201 to 250 6 251 to 300 9
(2) Buffers for Cars and Counterweights.
Buffers for cars and counterweights shall be of the following:
(A) Capable of supporting, without being compressed solid, a static load having a minimum of twice the total weight of the car and its rated load for car buffers, and the counterweight for counterweight buffers.
(B) Compressed solid with a static load of three times the weight of the car and its rated load for car buffers, and the counterweight for counterweight buffers.
EXCEPTION: When the requirements of Section 1604.5(b)(2) necessitate a greater load rating.
(3) Marking Plate.
Each spring buffer shall have permanently attached to it a metal plate marked in a legible and permanent manner to show its stroke and load rating.
(c) Construction and Requirements for Oil Buffers.
(1) When oil buffers are used they shall comply with Section 3031 of the Elevator Safety Orders.
(2) When oil buffers are used and the air temperature is below 0°F, means to maintain the temperature of the oil above 0°F or above the pour point of the oil, whichever is lower, shall be provided.
(3) Terminal speed limiting devices installed in connection with reduced stroke oil buffers shall conform to the requirements of Section 1604.23.