卓越培訓發展中心（電機業）首席教導員（電機）黃啟漢解釋，升降機內的懸吊纜索連繫著機廂及平衡鐵塊，驅動摩打令機廂向上，鐵塊便會向下。由於平衡鐵塊的重量是機廂總載重的一半，若意外發生時，機廂內的人數或載重不多，重量沒有超過總載重的一半，平衡鐵塊便會向下降，機廂就向上升。
舊款無防急升安全夾
對於今次事故，黃啟漢估計是升降機制動系統失靈所致，他形容制動系統失靈，會如汽車失去煞車一樣，運行速度越來越快，直至發生強力撞擊才會停低。黃指2007年後安裝的升降機，主軸備有安全夾，無論是向下墜或急升，安全夾會夾實升降機主軸，煞停電梯，而出事的升降機由於款式較舊，只配備防外墜的安全夾，無法防止急升。另外，有業內人士指，舊款升降機不配備鋼纜制動器，因此升降機一旦超速，升降機將「煞唔停」。
有專家解釋纜索曳引力不足是因為纜坑磨蝕，「咬不住」纜索導致滑纜，暫時難以斷定是否涉人為疏忽。
舊款無防急升安全夾
對於今次事故，黃啟漢估計是升降機制動系統失靈所致，他形容制動系統失靈，會如汽車失去煞車一樣，運行速度越來越快，直至發生強力撞擊才會停低。黃指2007年後安裝的升降機，主軸備有安全夾，無論是向下墜或急升，安全夾會夾實升降機主軸，煞停電梯，而出事的升降機由於款式較舊，只配備防外墜的安全夾，無法防止急升。另外，有業內人士指，舊款升降機不配備鋼纜制動器，因此升降機一旦超速，升降機將「煞唔停」。
有專家解釋纜索曳引力不足是因為纜坑磨蝕，「咬不住」纜索導致滑纜，暫時難以斷定是否涉人為疏忽。
荃灣海灣花園升降機意外，機電署指事故成因可能是制動系統，即剎停升降機的系統未能正常操作，或纜索曳引力不足。
現時常見的牽引式升降機，纜索僅僅掛在一個名為曳引輪的輪上，纜索會跟著曳引輪轉動。
有專家解釋指故事可能是曳引輪「咬不住」纜索導至滑纜。
有專家解釋指故事可能是曳引輪「咬不住」纜索導至滑纜。
至於為何纜坑會磨蝕掉，他指升降機的剎停系統可能出問題，令升降機曾經高速升降，磨蝕纜坑，暫時很難說是否涉及人為疏忽。
卓越培訓發展中心(電機業)首席教導員黃啟漢認為今次事件罕見，而新式的升降機已經有雙重剎停系統，比今次意外中的舊形號安全。
cablenews
In this connection, you are urged to thoroughly check the condition of the braking system
on each of your regular maintenance. The areas of your checking should include, but not be limited to, the correct setting of the system for providing adequate braking force (i.e. spring and lining setting), and that the operation of the brake should be smooth with moving parts free from rust and debris. You should also pay particular attention to the mechanical components of those brakes which were applicable to lift installations with tendering date before 1 March 2002 and equipped with a single solenoid plunger. This design is NOT up to the latest requirement stipulated in the Section E Part 1 Clause 8.4.2.1 of the Code of Practice on the Design and Construction of Lifts and Escalators (Design Code). You are also advised to thoroughly check the related electrical components closely if a closed-loop control system for the brake mechanism has NOT been provided to guarantee a successful changeover of holding a lift car at a stationary position from the electric lift motor to the mechanical brake during a normal stop of the lift car at a landing.
EMSD circular
cablenews
In this connection, you are urged to thoroughly check the condition of the braking system
on each of your regular maintenance. The areas of your checking should include, but not be limited to, the correct setting of the system for providing adequate braking force (i.e. spring and lining setting), and that the operation of the brake should be smooth with moving parts free from rust and debris. You should also pay particular attention to the mechanical components of those brakes which were applicable to lift installations with tendering date before 1 March 2002 and equipped with a single solenoid plunger. This design is NOT up to the latest requirement stipulated in the Section E Part 1 Clause 8.4.2.1 of the Code of Practice on the Design and Construction of Lifts and Escalators (Design Code). You are also advised to thoroughly check the related electrical components closely if a closed-loop control system for the brake mechanism has NOT been provided to guarantee a successful changeover of holding a lift car at a stationary position from the electric lift motor to the mechanical brake during a normal stop of the lift car at a landing.
EMSD circular
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