(1) Every Lift suspended by ropes shall be provided with safety gear attached to the Lift car frame and should preferably to placed beneath the Lift car platform.
(2) A pawl or ratchet shall not be held to constitute a sufficient safety gear for Lifts.
(3) The safety gear shall be capable of stopping and sustaining the Lift car with full contract load in the Lift car.
(4) The safety gear shall operate to stop and sustain the Lift car in the event offailure ofall suspension ropes, or in the event of the Lift car exceeding a predetermined speed in the descending direction when an over speed governor is fitted.
(5) No Lift car safety gear shall be permitted to stop an ascending Lift car. If an ascending Lift car is to be stopped on account of over speed, a safety gear shall be fitted to the counterweight for this purpose. An over speed governor may however be used to causethe motor control and the brake control circuits to be opened in the event of over speed in the ascending direction.
(6) The safety gear ofevery Lift having a travel exceeding 6 meters shall be operated by an over speed governor.
(7) The application of the safety gear shall not cause the Lift car platform to become out of level in excess of 4 ems. per metre measured in any direction.
(8) The motor control and the brake control circuits shall be opened at the time the safety-gear is applied.
(9) When the Lift car safety gear is applied, no decrease in the tension of any rope for applying the safety gear, or in the motion ofthe Lift car in the descending direction shall release the Lift car safety gear.
(I 0) No safety gear shall depend upon the completion or maintenance of an electric circuit for its operation.
(11) AII safety gears shall be applied mechanically and shall operate independently of any springs used in its construction. Vibration ofthe Lift car frame shall not cause the safety gear to be applied.
(12) Any rope used for applying the safety gear shall be supported by its own pulleys and properly guarded. Such pulleys shall be mounted independently ofany shaft carrying the Lifting ropes. Such guard shall be ofsteel or other suitable material.
(13) The gripping surfaces ofLift car or counterweight safety gears shall run free ofthe guides during the normal operation ofthe Lift.
(14) Any levers or cams operated by shafts shall be fasten to such shafts by means ofkeys in accordance with approved methods.
THEKOLKATAGAZETIE,EXTRAORDINARY, NOVEMBER 11, 2022 21
(15) Safety gears shall be designed to grip each guide and to operate on both guides equally and simultaneously.
(16) All bearings for actuating drums and screw shafts in connection with the safety gears shall be ofnon-ferrous metal.
(17) The counterweight safety gear and governor has to be provided in case ofhanging or floating pit.
( 18) Combination of instantaneous and oil buffer safety gear for speed not exceeding 2.5 meter/ second.
(19) Safety gears shall be ofthe following types:
(i) Safety gears of the instantaneous type may be used on Lift car having a contract speed not exceeding 1 metre per second;
a. Safety gears ofthe instantaneous typemay be used on Lift car having a contract speed not exceeding
1.27 metre per second;
b. Where the contract speed exceeds 1 metre per second safety gear ofthe following types shall be used;
(A) Gradual Wedge Clamp type.
(B) Flexible Guide Clamp type.
(20) The maximum stopping distances ofLift car with safety gears of gradual wedge clamp, and flexible guide clamp types with the contract load in the Lift car, and accordance with the table given below :
TABLE Maximum stopping distance Minimum stopping distance [Speed in metre with contract load with Attendant only in the Lift car per second] Gradual Wedge Flexible Guide Gradual Wedge Flexible Guide Clamp Type Metre Clamp Type Metre Clamp Type Metre Clamp Type Metre
1.52 2.13 0.53 0.46 0.15
2.03 2.36 0.76 0.51 0.23
2.54 2.67 1.22 0.56 0.31
3.05 3.05 1.44 0.64 0.38
3.56 3.43 1.93 0.71 0.46
4.06 3.73 2.51 0 81 0.5311 Note. The stopping distance shall mean the actual slide as measured by the marks on the guides.
NOTE: The followingformula shall be used to determine the maximum and minimum stopping distance for gradual wedge clamp andflexible guide clamp type safetiesfor car and counterweightfor all intermediate speeds:
SI= 145V2+256 S2= 51V2+12 S 1 = Maximum stopping distance in millimeters S2 = Minimum stopping distance in millimeters, and
(a) = Governor tripping speed meter per second