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Except that has mechanism to prevent hazard from the slider, a power press machine or a power shear machine( hereinafter referred to as the press or shear machine) shall have a safeguard, a safety die, be a particular-purpose press or shear machine, be an automatic press or shear machine (hereinafter referred to as the safeguard).
Because the nature of jobs to lead difficulties for making the safeguard, it should be at least provided with one or more safety devices set by Article 6.
Motors, gears, rotating-shafts, driving- wheels, driving-belts and other components of the press or shear machine referred to the first paragraph and those having a risk of causing hazards, shall have guard-shields, guard-fences, guard-grilles or other appropriate means to prevent a body part touching danger points.

The safeguard referred to the preceding Article, shall be capable of preventing a body part intervening the hazard zone of the slider moving and meet the following provisions:
1. Safeguard: being capable of preventing fingers touching through it or from outside.
2. Safety die: a gap between as following two members being less than 8 millimeters.
(1) the upper-half die and the lower-half die when the slider at the top dead center.
(2) for having a stripper, this referred to that between the upper- half die and the stripper, and that between the stripper and the lower-half die when the slider at the top dead center.
(3) the guide post and bushing.
3. A particular-purpose press or shear machine : having a construction to prevent a body part intervening a hazard zone.
4. An automatic press or shear machine: having a construction automatically to feed material, process and discharge finished workpiece.

The safety device of the press or shear machine shall have one of the following functions:
1. Interlocked guard safety device: it can prevent a body part intervening to the hazard zone while the slider in closingaction.
2. Two-hand control safety device:
(1) Safe-single-stroke safety device: It can make the slider stopped before two hands releasing from start buttons, control levers or other control devices (hereinafter referred to as the operating portion) reach the hazard zone.
(2) Two-hand start safety device: It can prevent two hands releasing from the operating portion to reach the hazard zone while the slider in closing- action.
3. Sensing safety device: it can make the slider stopped if a body part is closing to the hazard zone while the slider in closing- action.
4. Pull-back or push-out safety device: it can follow the slider moving to withdraw or push a body part out from the hazard zone.
The safety devices referred in the preceding subparagraphs shall be not easy impairment or alteration.

The safety device of the press or shear machine shall meet the following provisions:
1. Adapting to the type of the press or shear machine, the capacity, the numbers of stroke per minute, stroke and operating ways.
2. Adapting to the stop performance of each type of the press or shear machine for a two-hand control safety device or a sensing safety device respectively.

The distance between the operating portion of the slider and the hazard zone, or the distance between the sensing zone and the hazard zone, that related to the stop performance of the twohand control safety device or the sensing safety device set in the preceding Article subparagraph 2, shall be over the value calculated by the following equations separately :
1. Two-hand control safety device for safe- single -stroke:
D＝1.6（Tl＋Ts）
Where,
D: the safety distance, in millimeters.
Tl: the time that hands releasing from the operating portion of that device to the starting action of the protective stop mechanism, in millimeters.
Ts: the time that the protective stop mechanism starting action to the slider stopping, in milliseconds.
2. Two-hand start safety device:
D = 1.6Tm
Where,
D: the safety distance, in millimeters.
Tm: the maximum time that hands releasing from the operating portion to the slider reaching the lower dead center, in millimeters and calculated by the following formula,
Tm =(1/2 + 1 / numbers of clutch engagement) × the time required for one revolution of the crankshaft)
3. Photoelectric safety device: D＝1.6（Tl＋Ts）+C D:the safety distance, in millimeters.
Tl: the time that fingers intervening the sensing zone of that device to the starting of the protective stop mechanism, in millimeters.
Ts: the time that the protective stop mechanism starting action to the slider stopping, in milliseconds.
C: an additional distance, in millimeters, and the adopted value as shown in the following table:

┌────────────────┬─────────────┐
│continuous shading width: mm    │additional distance C: mm │
├────────────────┼─────────────┤
│below 30                        │  0                       │
├────────────────┼─────────────┤
│over 30, below 35               │200                       │
├────────────────┼─────────────┤
│over 35, below 45               │300                       │
├────────────────┼─────────────┤
│over 45, below50                │400                       │
└────────────────┴─────────────┘

The interlocked guard safety device shall meet the following provisions:
1. Except in an inching state, it has a construction that the slider cannot be closed until the guard device is closed and it cannot be opened while the slider in closing- action.
2. Limit switches that enact the slider can prevent a body part, materials or others not belong to the protective device contacting.

The two-hand control safety device shall meet the following provisions:
1. It has a safe- single- stroke safety device, except the press or shear machine with single- stroke- single- stop mechanism and a two-hand start safety device.
2. It has a safe- single-stroke safety device to make the slider stopped when released hands having a risk to reach the hazard zone.
3. It has a two-hand start safety device to make the slider to reach the lower dead center before released hands intervening to the hazard zone.
4. It has a construction that the operating portion for activating the slider cannot be activated except the different of operating time between two hands is less than 0.5 second.
5. It has a construction that the press or shear machine cannot be restarted if two hands do not release from the single stroke operating portion.
6. The distance between one button outside and the other button outside is at least 300 millimeters. It can be reduced for the buttons with covers, baffles, barriers or others having the same safety function to prevent them being operated by a hand or other part of the body.
7. If the buttons are set in boxes, they cannot protrude the button-box surface.
8. If the buttons are built into the body of the press or shear machine, they cannot protrude the surface of the machine.

The sensing safety device shall be a photoelectric safety device, a photoelectric safety device with start control function, a laser-sensing safety device or others with equal or over performance.

The constructure and performances of the photoelectric safety device shall comply with the international standard IEC 61496 series or other equivalents.

The photoelectric safety device shall comply with the following provisions:
1. The photoelectric safety device for the press or shear machine can make the slider stopped when detecting the light cut off by a body part.
2. The photoelectric safety device for the press machine can effectively act to prevent hazard from the slider in required distance including adjustment length and stroke(hereinafter referred to as the protective height).
3. The optical-axis of the emitter and receiver shall be over two and can detect the minimum diameter of a shading rod (hereinafter referred to as the continuous shading width) being below 50 millimeters when it is placed anywhere in the protective height referred in the preceding subparagraph. The continuous shading width shall be less than 30 millimeters for that has a function of start control.
4. The optical-axis height from the desktop of the shear machine shall be less than 0.67 times of the horizontal distance between the vertical plane including the optical- axis and the hazard zone. The height could be concerned as 180 millimeters when over 180 millimeters.
5. The emitter and receiver referred in the preceding subparagraph shall have at least one another optical-axis between the former optical-axis and the cutter when the horizontal distance from the vertical plane including the former optical-axis to the hazard zone is over 270 millimeters.
6. The photoelectric safety device for the press or shear machine has a construction that the light from the emitter can only reach its corresponding receiver or reflector, and cannot be sensed by other sensors. It is unrestricted for that not affecting the slider motion even being other light sensed.

If the distance between the optical- axis of a detecting mechanism and the front edge of a bolster is enough to be intervened by a body part, the press or shear machine with a photoelectric safety device shall have a safety fence or a middle optical-axis to prevent intervening.

The photoelectric safety device for the press machine with a material feeder can make that feeder detecting invalidated without restricting by Article 12, subparagraph 2 if the emitter and receiver of that safety device complies with the provisions in subparagraph as follows:
1. The switching to make that detecting invalidated, shall be used by a key , software or others for each optical-axis.
2. When changing a material feeder device, the slider cannot be activated except the detecting invalidated in the preceding subparagraph is reset.
3. When the material feeder is taken away, it has a construction immediately to restore the effective action that the emitter and receiver within the required length can prevent the hazard of the slider motion.

The photoelectric safety device with a start control function shall have a construction to make the slider stopped when it detect a body part cutting the light. The press or shear machine using a photoelectric safety device with start control function, shall meet the following provisions:
1. The distance of the bolster surface from the ground is above 750 millimeters but it is unrestricted for having a safety fence between the bolster surface and the lower end of the emitter and receiver.
2. The depth of the bolster is less than1,000 millimeters.
3. Stroke is less than 600 millimeters but it is unrestricted for the press or shear machine having a safety fence and the protective height of the emitter and receiver being less than 600 millimeters.
4. The stop- point-setting of the over- fix-point monitor for a crankshaft press machine is within 15 degrees.
The emitter and receiver of the photoelectric safety device with a start control function shall have the construction not easily to be disassembled or to be changed its mounting place. When using the photoelectric safety device with the start control function, it shall be able to prevent the slider moving unexpectedly and meet the following provisions:
1. The photoelectric safety device with the start control function shall use a key to select the hazard-preventive function.
2. It shall have the construction to finish the necessary start preparing operation before making the slider moved.
3. It shall have the construction to finish the necessary start preparing operation related in the preceding subparagraph if the slider do not move within 30 seconds.
The photoelectric safety device with the start control function corresponds with the application of Article 8 and Article 12 provisions. However, the additional safety distance for that device set in Article 8 is reduced as following table:

┌───────────────┬──────────────┐
│Continuous shading width:     │Additional distance C:      │
│millimeters                   │millimeters                 │
│                              │                            │
├───────────────┼──────────────┤
│less than 14                  │   0                        │
├───────────────┼──────────────┤
│more than 14 and less than 20 │  80                        │
├───────────────┼──────────────┤
│more than 20 and less than 30 │  130                       │
└───────────────┴──────────────┘

A laser-sensitive safety device for a press brake shall have the following performances:
1. A construction can make the slider stopped when it detects a body part shading the light and the slider has a risk to catch the body.
2. A construction can make the slider speed reduced to be less than 10 millimeters (hereinafter referred to as the low closing speed) when it detects a body part or a workpiece shading the light or the slider is asked to keep moving in closing action even the slider having reached a set position.
A laser-sensing safety device can be applied to a press brake complying with the following provisions:
1. A construction can adjust the slider to the low closing speed when it is in closing move.
2. A construction can make the slider not activated in the low closing speed except it is operated at the operating portion.
The detecting construction of the laser-sensitive safety device for a press brake shall have the following performances:
1. The emitter and receiver is provided at the location where a body part may be caught by the slider. If the slider of the press brake is a dropping type, the construction of the detector has the motion in conjunction with the slider motion.
2. A construction can make detecting function invalidated while the slider is in closing motion and the low closing speed.

The pull-back safety device shall meet the following provisions:
1. If it is set by traction cables, the cables are able to adjust the amount of traction and that is more than a half of the bolster depth.
2. The cable material is a synthetic fiber with the diameter more than 4 millimeters. In adjustable metal parts fitted state, the breaking load of it is over 150 kgf (1.5 kN).
3. The toggle- transfer belt is made of leather or other equivalent material and the cable connection portion can withstand more than 50kgf (0.49kN) static load.

The push-out safety device shall meet the following provisions:
1. It has a construction that the length and the amplitude of a push-out arm are adjustable.
2. The push-out arm sets a hand- guard plate to ensure the hand safety when the slider moving.
3. Sizes of the hand- guard plate in the preceding subparagraph are as follows:
(1) the width: more than one half width of a die but it being concerned as 100 millimeters for that less than 200 millimeters.
(2) the height: more than the stroke but it being concerned as 300 millimeters for the stroke more than 300 milimeters.
(3) the amplitude of the push-out arm: more than the die width.
4. The push-out arm and the hand- guard plate have the performance mitigating the impact when they contact with hands or a body part.

The press machine cannot provide the push-out safety device except that complies with the following provisions:
1. The construction is a positive clutch type and the operating portion to start the slider shall be controlled by two hands.
2. The stroke must be more than 40 millimeters and less than the protect-plate width.
3. Strokes per minute must be less than 120. The press machine with the protective stop mechanism operated by a foot type cannot use a push-out safety device except it use one of safety devices set in Article 6 subparagraph 1 through 3.

Mechanical parts, electrical parts, wires, switches or other parts for the safety device of the press or shear machine shall meet the following provisions:
1. The body, the linkage material, the lever and other major mechanical parts have sufficient strength.
2. Linking parts:
(1) Their materials comply with the national standard CNS 3828 “mechanical-structure-usage carbon-steel material” S45C or others having equivalent or more mechanical properties.
(2) The surface of linking parts is treated by quenching and tempering, and their hardness must be above 45 to 50 in Rockwell C scale.
3. Wire cables:
(1) They comply with the national standard CNS 10000 “machinery-control-usage cable” or others having equivalent or more mechanical properties.
(2) They are tightly fixed on the slider, levers and others with clips, clamps and so forth.
4. Preventing loosing shall be applied to bolts, nuts and others on the safety device that may lead the device being malfunction or fitting parts falling off. Preventing falling off shall be applied to pins on the hinge portion too.
5. Relays, limit switches or other major electrical parts shall have sufficient strength and durability to ensure safety device performances.
6. The safety device with electrical circuits shall have indicators to display its actuated states, relay malfunction or failure of other circuits.
7. Mounting portions for relays, transistors, capacitors, resistors or other electrical parts have vibration-proof performance.
8. Circuits in safety device have the performance to prevent the slider accidental action when relays, limit switches or others are failure or power-failure.
9. Operating voltage for the electrical circuit shall be less than 160 volts.
10. External wires shall meet the national standard CNS 6556 “600V PVC insulated and coated light weight cables” or have equivalent or more insulation, oil-resistance, strength and durability.
11. Switches:
(1) For a button-switching type of the safety device, it shall have a construction to let buttons selecting switching positions respectively.
(2) It can exactly keep holding at each switching position.
(3) It is clearly to mark the state of the safety device related to each switch position.

The press or shear machine having one of the following switches shall have the safety function to comply with that in Article 4 in any switching state.
1. The switch for the switching of a continuous- stroke, a single- stroke, a safe- single- stroke , an inching-stroke and so forth.
2. The switch for one- hand control instead of two-hand control, or pedal control in stead of two-hand control.
3. The switch for one- console control instead of multi- control consoles.
4. The switch of the safety device for setting the operation of that switching in "On" or "Off".

The stroke changing switch and operation changing switch for the press machine shall comply with the following provisions:
1. For those being a key-switching type, their keys can be taken away in any switching position. It is without restrict for anyone of following states:
(1) The press machine in any switching state has one of safety functions in Article 6 subparagraph 1 through 3.
(2) Switchings are operated by a password.
(3) The switches have other equivalent safety control functions.
2. Swithes can exactly be held in the respective switching position.
3. Switchings shall clearly mark all stroke modes and operation means.

The press machine shall have an one- stroke- one- stop mechanism.

A servo press machine with a servo system to make the slider reduced or stopped shall have a braking construction to stop the slider when the servo system fails.
When the braking in the preceding paragraph occurs abnormal, the slider shall be stopped and cannot be started even the restarted operated.
The servo press using a belt or a chain to drive the slider shall have the construction to prevent hazard from the belt or the chain broken.

The press machine shall have the protective stop mechanism except one of the following states:
1. Using a positive clutch.
2. Having a construction to prevent a body part entering the hazard zone.
3. Having a construction to prevent a body part entering the hazard zone during the slider in moving.
The press machine shall have a construction that the slider cannot move without re-start operating after the protective stop mechanism activated.

The press machine with the protective stop mechanism shall have a device that the protective stop mechanism can be manually operated to make the slider stopped when an emergency occurs.
The press machine shall have a construction that the slider cannot move if it do not return to the original-start position after the emergency stop device activated.

The operating portion for the emergency stop device of the press machine shall meet the following provisions:
1. They have red- protruding- type buttons or others with significant identification to be quickly, efficiently and manually operated.
2. They are provided in each operating zone.
3. For the press machine with straight sides or other similar models, whose maximum distance between both straight sides is over 1800 millimeters, the emergency stop devices shall be set respectively in the front side and the rear side.

The press machine with the protective stop mechanism shall have an inching mechanism.
The above- mentioned inching mechanism shall have at least one of the following devices for controlling the slide movement:
1. slow closing speed (equal or less than 10 mm/s) of the slides;
2. The slide movement shall not exceed 6 mm per inching step, while the press or shear machine cannot be restarted if the operator has not released their two hands from the operating portion.
If the press referred to in the first paragraph is equipped with safety devices to prevent a body part entering the hazard zone, their inching mechanism is not restricted by the requirements of the first paragraph in this Article.

The press machine shall have a safety stopper or a fix- slider device to prevent the slider accidently falling, while featuring an interlocked construction that cannot activate the slider when the stopper or the fix- slider device is used. As the following press machines find it difficult to use that, they can use a safety plug, a safety lock or other devices with an equivalent function.
1. A press brake.
2. Except the press brake, the machine press with each bolter-side-length below 1500 millimeters or the die-height below 700 millimeters.
The proviso for the safety plug or the safety lock in the preceding paragraph shall meet the following provisions:
1. The safety plug is provided in each operating zone of the press machine.
2. The safety lock can block the main motor power of the press machine.
The safety stopper or the fix-slider device in the paragraph 1 shall have the strength to support the total weight of the slider and the upper half die.

The operating portion of the press or shear machine shall have one of the following constructions:
1. to prevent the slider unexpectedly starting up due to inadvertent touching.
2. the slider cannot move without re-starting the operation.
The above-mentioned machinery with mode switching and continuous-stroke shall have a mechanism and construction to prevent the movement of the slider in the case of mistaken operation of the mode switching.

The electrical systems of the press machine shall meet the following provisions:
1. Indicators or other equivalent functional devices are provided to show operating status.
2. Mounting zones for relays, transistors, capacitors, resistors, other electrical parts, control panel, the operation panel or the main body of the press machine have vibration prevention capacity.
3. The electrical circuit for the main motor driving has the function that the main motor cannot be restarted after the end of a power outage unless restart is activated. The above-mentioned requirements may not apply if the machinery is constructed to prevent a body part entering a hazard zone.
4. The electrical circuit for control or operation has the function to prevent unexpected action by the slider in the case of failures by relays, limit switches or other electrical parts, voltage drops or power outage. The above-mentioned requirements may not apply if the machinery is constructed to prevent a body part entering a hazard zone.
5. The operating voltage for the electrical circuit is less than 160 volts.
6. External wires shall meet the national standard CNS 6556 "600V PVC insulated and coated light weight cables" or others having equivalent or more insulation, oil-resistance, strength and durability.
7. Relays, limit switches or other major electrical parts in electrical circuits for controlling or operating shall have sufficient strength and durability.

Springs, bolts, nuts, bushings, pins or others for the press machine shall meet the following provisions:
1. Springs are compression type and guided by rods, pipes or others if the slider have an accident motion risk because of springs broking or dropping out.
2. Preventing loosing shall be applied to bolts, nuts, bushings and others that may lead the slider to unexpectedly move or fitting parts to fall off.
3. Preventing loosing shall be applied to pins that may lead the slider to unexpectedly move or fitting parts to fall off.

A clutch of the mechanical press shall have a construction that a main motor cannot be driven when the clutch is in engagement state and the slider stopped but it is unrestricted for having a construction to prevent a body part intervening a hazard zone.

The stroke numbers of a mechanical press with a sliding-pin clutch (hereinafter referred to as the pin clutch mechanical press) or a rolling-key clutch (hereinafter referred to as the key clutch mechanical press) cannot be over that in Attachment table 1.

Materials used in the clutches related to that mechanical press in preceding Article 28 shall have mechanical properties to comply with the national standard in Attachment table 2 or others having equivalent or more.

The heat treatment and surface hardness of those clutches related in Article 28 shall base on the type of the mechanical press and the construction of those to comply with provisions in Attachment table 3.

For those clutches in Article 28 which is pneumatic activating, shall have a spring-release construction or others having equivalent or more safety functions.

The clutch of the pin clutch mechanical press shall have a stopper to stop the crankshaft revolution before a clutch driving cam do not exceed the scope of the clutch slide- pin yet to return back.
The clutch bracket used by the clutch in the preceding paragraph shall have a positioning pin to fix its position.
The clutch-driving cam shall have a construction that it cannot be pressed back if not being acted.
The mounting portion for the clutch-driving cam shall have enough strength to support the impact on the cam.

The clutch of a mechanical press brake shall use a friction-type clutch.

The brake device of the mechanical press with an eccentric mechanism such as a crankshaft (hereinafter referred to as the crankshaft press) shall have a construction that its braking surface cannot be invaded by fat, oil or others but it is unrestricted for the wet-braking type.

The brake device of the crankshaft press that braking is activated with a pneumatic clutch, shall be a spring- fastening type or others having equivalent or more safety function.
The brake device of the crankshaft press except the press mentioned in the preceding paragraph, shall be a non- band braking type but it is unrestricted for a crankshaft press with a capacity less than 100 tons and not a mechanical press brake.

The crankshaft press shall have indicators or others having equivalent function to show the angle of the crank rotation in obvious position.

The stopping angle of the crankshaft for the pin clutch or the key clutch mechanical press shall be within 10 degrees but it is unrestricted for having a construction to prevent a body part intervening a hazard zone.
The above mentioned stopping angle refers to the crank center angle formed by the set stop point and the actual stop point.

The crankshaft press with a crankshaft revolution below 300 revolutions per minute shall have a system to monitor excessive speed. But the above-mentioned requirements may not apply to crankshaft presses which do not need to include the protective stop mechanism according to rules, or which are constructed to prevent a body part entering the hazard zone.
The monitor in the preceding paragraph means that a directive can activate the protective stop mechanism when the crankshaft cannot be stopped at the set-stop point.
The above-mentioned set-stop point shall have a stopping angle within 25 degrees from the set-stop position.

The mechanical press that clutch or brake is controlled by pneumatic or hydraulic shall provide the following solenoid valves:
1. Multi-acting solenoid valves except that having a construction to prevent a body part intervening the hazard zone.
2. Normally closed solenoid valve.
3. Being pressure-return type for the solenoid valve controlled by the pneumatic.
4. Being spring-return type for solenoid valve controlled by the hydraulic.

The mechanical press mentioned in the preceding Article shall have a safety device to prevent excess pressure of the pneumatic or hydraulic pressure of the clutch or brake and to cause the slider to stop automatically when the pressure is below the set value, which may not apply if the safety requirement is met by using a servo-system that can prevent inadvertent action when the pneumatic or hydraulic pressure goes beyond the set value.

The mechanical press with a slider adjusting by an electric motor shall have a device to prevent the slider adjusting beyond its upper or lower limits.

The counter-balancer of the slider for the mechanical press shall meet the following provisions:
1. A spring-type counter-balancer : a construction to prevent spring or other parts scattered when it occurs damage.
2. A pneumatic-type counter-balancer:
(1) a construction to prevent piston or other parts scattered when it occurs damage.
(2) a construction that the slider and its accessories shall be held at any position in the stroke when the brake device is not operated, and it can automatically stop the slide acting when the pressure falls below the set.

The positive-clutch mechanical press with a foot control switch or a foot pedal, strokes per minute less than 150, and the capacity below 150 tons, shall have a construction that can prevent a body part entering the hazard zone or have the protective stop mechanism.

The positive- clutch mechanical press with strokes per minute over than 150 or the capacity over 150 tons shall not be provided the protective stop mechanism.

A hydraulic press shall have a construction that the slider cannot be activated without doing the start operation after a hydraulic pump started.

An over drop distance (inertial descending value) of the slider shall be less than the value in Attachment table 4 when the protective stop mechanism in the hydraulic press acts on the slider being of a maximum dropping speed.

The hydraulic press shall have a safety stopper to support the total weight of the slider and the upper half die.

The solenoid valve in the hydraulic press or shear machine shall be a normally closed type with a spring-return construction.

The hydraulic press or shear machine shall have a safety device to prevent that hydraulic pressure goes beyond the set value.