Belt Conveyor Safety - Emergency Stop Button & Emergency Stop Pull Cords

Dear All,
I am initiating this thread to discuss and come to a conclusion on the requirement of emergency stopping devices in the belt conveyors. If Pull Cords installed in the entire length of a belt conveyor, is that sufficient protection?
Do we need to have Emergency Stop Buttons along the entire length of the conveyor in addition to this pull cords?
The below website mentioning the need for pull cords & push buttons in the entire length of belt conveyors...
https://www.hsa.ie/eng/Your_Industry..._-_pull_wires/
Does anyone of your sites have this E-Stops in the entire length of conveyor apart from Pull Cords as safety protection means?
Is this a legal requirement in any part of the world or just a best management practice only?
Do let me know your thoughts on this...

If any workforce required checking the conveyor belt, and the pulleys, for foreign particles, then it is better to provide powerful sensor near the pulleys. I had come across an accident, when the pickers picking foreign partials (metals) in lime stone conveyor belt to crusher, in cement industry, the worker head was pulled in along with his turban, between the pulley and the conveyor belt, inspite of having provided enough pull cords & push buttons provided. The worker body went in between the conveyor and pulleys and died on the spot. The belt tripped very late.

Dear Sir,
I appreciate the response.
What you mean by “provide a powerful sensor near the pulleys?” Is that something beyond the Emergency Stops and Pull Cords? Are you referring to provide some Light curtains sort of installation?
Can you please comment on the need of providing the Emergency Stops across the length of the conveyor in addition to having the pull cords? This will serve as a secondary means of protection, in case the full cords fail to function.

Mr.Dipil Kumar
I mean light curtain / sensor normally provided in elevator. The most dangerous area is the pulleys, where the conveyor belt rotates. Some time hands, fingers can be pulled in, though trip/over load switch is provided.
The Need to providing emergency stop switch / or pull cord is, basically when the pickers find some foreign particles which can damage the crushers jaws (mostly the metal teeth form the excavators) or some different kind of stones which can deteriorate the quality of the lime stone, they have to stop on conveyor belt on that line and pick and remove it.

Dear Sir,
Thanks for the response.
Did you came across any conveyors in India or anywhere in the world in which light curtain/sensors installed apart from the pull cords/emergency stops? If yes, can you please share some more details about it with a photograph, if possible.
Regarding the emergency stop and pull cords, I can understand from your post, that we need any one of the above only.
However, the need for providing emergency stops in the entire length of conveyor apart from the pull cord is a legal requirement in Canada and in Ireland. I am looking for more references and logical reasoning to suggest this to my client.

Most of the lime stone quarries, belonging to the Associated Cement Companies limited, installed sensors near pulleys, where the conveyor belt carries lime stone to crushers, from quarry yard.

Dear Sir,
Thanks for that information.
Let me try to ger more information on this.
Looking forward to getting more comments on the emergency stop requirements in the conveyor belt.