Rules on Occupational Safety and Health Standards

Article 222 (Teaching, etc.) When it is required to perform works such as teaching [this refers to setting or changing the operation sequence, position and speed of the manipulator, or checking the result, and will be the same in the following] on the robot within the operation range of an industrial robot (hereinafter referred to as “robot”), the business owner is required to take the measures described under the following items to prevent the danger that could be caused by the unexpected operation of or mistakes in the operation of the robot. However, if the works are performed with the robot’s driving source cut off, measures #1 and #2 below may not be taken <Revised on April 7, 2016>.

1. Establish guidelines for the following items, and make sure that works are performed according to the guidelines.

A. Robot operation method and sequence

B. Manipulator speed during a work

C. Signaling method when having two or more workers to carry out works

D. Measures to take when finding an abnormality

E. Measures to take when finding an abnormality and stopping the operation of the robot and restarting the operation

F. Other measures necessary to prevent the danger that could be caused by unexpected operation of or mistakes in operation of the robot

2. Workers engaged in the works or those who monitor the workers should take measures to stop the operation of the robot immediately if an abnormality is found.

3. In the process of performing works, it is required to take measures such as putting up a marking on the start switch, for example, to indicate that works are underway, to prevent workers other than the ones currently engaged in the works from manipulating the start switch.

4. Article 223 (Prevention of Dangers during Operation) The business owner is required to install a fence of 1.8 m or more in height (the height can be adjusted lower if there is no danger that could be caused due to the height when considering the operation range of the robot) to prevent the risk of workers being injured that may occur because of the operation of the robot (excluding the operation of the robot for the teaching according to Article 222 and also the operation of the robot in compliance with conditions of Article 224). In some sections where a fence cannot be installed because of the installation of a conveyor system, etc., a responsive protective device such as a safety mat or optoelectronic protective device should be installed. However, if the Minister of Employment and Labor acknowledges that the safety standard for the robot meets the safety standards set by Korean industrial standards under Article 12 of the Industrial Standardization Act or internationally accepted safety standards, it is possible to forego measures according to the text of this document.

5. Article 224 (Including the measures to take when performing works such as repairing) When the work such as repairing, inspecting, adjusting (excluding teaching), cleaning, refueling the robot or confirming relevant results within the operation range of the robot is underway, the business owner should take necessary measures such as locking up the start switch of the robot by using a key and managing the key separately, or putting up a signboard on the start switch indicating that a work is underway, to ensure that the robot can be stopped, and, at the same time, anyone other than the workers engaged in the work should be prevented from manipulating the start switch. However, this is not the case if a work must be performed even during the operation of the robot, and, in such situation, measures of the individual items under Article 222 are taken to prevent the danger that could be caused by an unexpected operation or mistakes in operation.

	【Appendix 14】Inspection Standards for Industrial Robots (Related to Article 30)
Automatic operation mode	A. In the automatic operation mode, safety devices such as fences should maintain the normal function, and if a person enters the protected area, the protective stop function should be activated. B. Protective stop or emergency stop should not be reset or disabled when the automatic operation mode is selected. C. Automatic operation mode should be deactivated when a stop signal is given. D. When the automatic mode is selected, the starting of the automatic mode should be possible only by a separate start operation outside the protected area. E. Changing from automatic operation mode to other operation modes should be possible only when driving is stopped.
Control of the pendant	If the pendant has a string, its length should be sufficient for the teaching operator to perform the work safely.
Electric connection devices	Electric connection devices such as electric outlets that are to be connected to the robot should not be separated arbitrarily.
Robot system layout design	The layout of the robotic system for the operation area, access, and free space should be appropriate in compliance with the following items. A. The maximum area of the robot should be checked first. Then, the restricted area and operation area should be set, and there should be a free space between the robot and obstacles such as pillars of the building. B. A passage such as a pedestrian passage should be secured for safe passage. C. Access to and from the path for the control system should be safe. D. A safety passage for approaching inspection, cleaning, repair, maintenance, etc. should be secured. E. There should be no risk of slipping, tripping, or falling over due to wiring or other dangerous sources. F. There should be no danger caused by the cable tray, etc. G. Operation controllers and auxiliary equipment (welding controllers, pneumatic valves, etc.) that workers need to access during automatic operation should be located outside the protected area.
Robot system stop function	All robot systems should have a protective stop function and also a separate emergency stop function. A. Emergency stop function 1) The robot system should have a single emergency stop function that operates for all relevant parts of the system. 2) In the case of multi-robots or multi-cells, the control range can be divided, and the control range should be clearly indicated using characters or symbols near the emergency stop device. 3) When there are more than two control positions, the emergency stop device installed in each control position should always maintain its function. 4) This function should take priority over all other robot controls and, in case of an emergency stop, should remove the driving power from the robot drive unit and maintain the stop state until initialization. 5) Initialization should be performed manually only, and restarting should not be performed immediately after initialization but should be carried out through a separate starting operation. 6) The performance of the emergency stop circuit should satisfy the safety related control system performance requirements of item no. 4. B. Protective stop function 1) The robot system should be equipped with one or more protection stop circuits for connection with external protection devices. 2) When activated, the protective stop circuit should be capable of stopping the robot operation, removing the actuator power, and controlling all dangerous sources controlled by the robot. 3) Protective stop should be started manually or by control logic. 4) At least one protection stop function should be 0 stop method or 1 stop method Note 1) 0 stop method: Stopping will be performed through immediate cut-off of the actuator power Note 2) 1 stop method: the power will be cut off after the machine stops while the actuator power is supplied. 5) The performance of the protective stop circuit should satisfy the safety-related control system performance requirements of item no. 4.
Manual resetting, staring and restarting	The robot system should be appropriate in compliance with the following items to prevent unexpected starting. A. Starting and restarting should be possible only when all safety functions and protective measures are operating normally. B. If the power supply is interrupted and then resumed, a starting interlocking device should be installed to prevent the automatic starting of dangerous operations and should be reset only by manual operation. C. Start and restart control should be manually operated outside the protected area and should be impossible to activate within the protected area. D. The start and restart control unit should be located where the protected area can be visibly seen. However, if it is difficult to secure a view of the protected area, it is required to comply with one of the following items. 1) Installation of a detection device that can detect the presence of workers in the protected area 2) Installation of means to keep the door open 3) Installation of an additional device for time limit reset inside the protected area 4) Generation of audible and visual warning signals that can be sufficiently recognized inside the protected area, and provision of sufficient evacuation time E. When it comes to complying with item 4) of D above, it is required to install a sufficient number of emergency stop devices in the protected area at a location that the operator can access easily.
Protected area, fence. etc.	Protected areas and measures should be appropriate in compliance with the following items. However, in the case of cooperative robots, some applications may be excluded depending on the operation method. A. The restricted area should be located within the protected area B. The protected area should be established by means of a fence. However, when it comes to an opening for taking in and out materials or parts, the protected area should be established by a responsive protective device, etc. C. The fence for the robot cell should be appropriated in compliance with the following items. 1) The fence should be firmly installed so as not to be easily damaged by external force and should be of a structure that can be removed only with tools. 2) If the fence has an opening for taking in and out materials or parts, it is required to physically prevent workers from accessing dangerous points under, next to, or through the opening, and if such measures are not possible, it is required to take additional measures such as using responsive protective devices. 3) The height of the fence should be over 1,800 mm. However, if there is no danger that could be caused due to the height, in consideration of both the operation range of the robot and the safety distance according to KS B ISO 13857, the height of the fence may be over 1,400 mm. 4) The movable fence (entry door) should be opened to the side or in the direction of moving away from a source of danger, and should be structured in a way that it does not open toward the protected area. 5) An interlocking device should be installed to the movable fence (entry door), and it should be able to turn the source of danger into safe state before the workers approach it. However, if there is a possibility of accessing the dangerous area before the source of danger is removed, there should be a locking device for the entry door in addition to the interlocking device. 6) The movable fence (entry door) locking device should allow the start of the robot only when the movable fence (entry door) is closed and locked.