This annex establishes references to safety distances and requirements for the machines and equipments in general. The provisions of the specific standards and annexes shall be observed, where applicable.
A) Safety distances to prevent danger zones being reached when physical barriers are used
TABLE I
Safety distances to prevent danger zones being reached by the upper limbs (dimensions in milimeter – mm)
| Part of Body |
Illisturation |
Opening – e |
Safety Distance – ds |
||
|
Slot |
Square |
Round |
|||
| Finger tip |  |
e ≤ 4 | ≥ 2 | ≥ 2 | ≥ 2 |
| 4 < e ≤ 6 | ≥ 10 | ≥ 5 | ≥ 5 | ||
| Finger up to knuckle joint or hand |  |
6 < e ≤ 8 | ≥ 20 | ≥ 15 | ≥ 15 |
| 8 < e ≤ 10 | ≥ 80 | ≥ 25 | ≥ 20 | ||
| 10 < e ≤ 12 | ≥ 100 | ≥ 80 | ≥ 80 | ||
| 12 < e ≤ 20 | ≥ 120 | ≥ 120 | ≥ 120 | ||
| 20 < e ≤ 30 | ≥ 850* | ≥ 120 | ≥ 120 | ||
| Arm up to junction with shoulder |  |
30 < e ≤ 40 | ≥ 850 | ≥ 200 | ≥ 120 |
| 40 < e ≤ 120 | ≥ 850 | ≥ 850 | ≥ 850 | ||
| * If the length of the slot opening is ≤ 65 mm, the thumb will act as a stop and the safety distance may be reduced to 200 mm. | |||||
Source: ABNT NBR NM-ISO 13852:2003 – Safety of Machinery – Safety distances to prevent danger zones being reached by the upper limbs.
Figure 1. Reaching over protective structure. To use Table II, note the Symbols for Figure 1.
Symbols:
a: the height of danger zone;
b: the height of protective structure;
c: the horizontal distance to danger zone.
1: Reference plane
2: Danger zone
3: Protective structure
TABLE II
Reaching over protective structure – High risk (dimensions in mm)
| Height of protective structure, b¹ | ||||||||||
| 1000 | 1200 | 1400² | 1600 | 1800 | 2000 | 2200 | 2400 | 2500 | 2700 | |
| Height of danger zone, a | Horizontal distance to the danger zone, c | |||||||||
| 2700³ | – | – | – | – | – | – | – | – | – | – |
| 2600 | 900 | 800 | 700 | 600 | 500 | 400 | 300 | 200 | 100 | – |
| 2400 | 1100 | 1100 | 900 | 800 | 700 | 600 | 400 | 300 | 100 | – |
| 2200 | 1300 | 1200 | 1000 | 900 | 800 | 600 | 400 | 300 | – | – |
| 2000 | 1400 | 1300 | 1100 | 900 | 800 | 600 | 400 | – | – | – |
| 1800 | 1500 | 1400 | 1100 | 900 | 800 | 600 | – | – | – | – |
| 1600 | 1500 | 1400 | 1100 | 900 | 800 | 500 | – | – | – | – |
| 1400 | 1500 | 1400 | 1100 | 900 | 800 | – | – | – | – | – |
| 1200 | 1500 | 1400 | 1100 | 900 | 700 | – | – | – | – | – |
| 1000 | 1500 | 1400 | 1100 | 800 | – | – | – | – | – | – |
| 800 | 1500 | 1300 | 900 | 600 | – | – | – | – | – | – |
| 600 | 1400 | 1300 | 800 | – | – | – | – | – | – | – |
| 400 | 1400 | 1200 | 400 | – | – | – | – | – | – | – |
| 200 | 1200 | 900 | – | – | – | – | – | – | – | – |
| 0 | 1100 | 500 | – | – | – | – | – | – | – | – |
| 1) Protective structures lower than 1000 mm are not included because they do not sufficiently restrict access of the body. 2) Protective structures lower than 1400 mm should not be used without additional safety measures. 3) For danger zones above 2700 mm, refer to Figure 2. |
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| There shall be no interpolation of the values given in Table 2. Consequently, when the known values of “a”, “b” or “c” are between two values in Table 2, the values to be used are those which provide the higher level of safety. | ||||||||||
Source: ABNT NBR NM – ISO 13852:2003 – Safety of Machinery – Safety distances to prevent danger zones being reached by the upper limbs.
Figure 2: Reaching upper danger zones.
Symbol: h: the height of danger zone
If there is a low risk from the danger zone, then the height of the danger zone “h” shall be 2500 mm or more.
If there is a high risk from the danger zone,
– the height of the danger zone “h” shall be 2700 mm or more, or
– other safety measures shall be used.
Source: ABNT NBR NM – ISO 13852:2003 – Safety of Machinery – Safety distances to prevent danger zones being reached by the upper limbs.
TABLE III
Reaching round – Fundamental movements (dimensions in mm)
|
Limitation of movement |
Safety distance, ds |
Illustration |
| Limitation of movement only at shoulder and armpit |
≥ 850 |
 |
| Arm supported up to elbow |
≥ 550 |
 |
| Arm supported up to wrist |
≥ 230 |
 |
| Arm and hand supported up to knuckle joint |
≥ 130 |
 |
| 1 The range of movement of the arm. a The diameter of a round opening, or the side of a square opening, or the width of a slot opening. |
||
Source: ABNT NBR NM-ISO 13852 – Safety of Machinery – Safety distances to prevent danger zones being reached by the upper limbs.
B) Calculation of minimum safety distances for the installation of optoelectronics presence detectors – ESPS using light curtain – AOPD.
1. The minimum distance, at which ESPS using light curtain – AOPD shall be positioned in relation to the danger zone, will observe the calculation according to ISO 13855. The distance for a perpendicular approach can be calculated in accordance with the general formula given in Section 5 of ISO 13855, as follows:
S = (K x T) + C
Where:
S: is the minimum distance in millimeters, from danger zone to the point, line or plane of detection;
K: is a parameter in millimeters per second, derived from data of the approach speed of the body or body parts;
T: is the stop performance of the entire system – total response time in seconds;
C: is the additional distance in millimeters, based on the intrusion into the danger zone before the actuation of the protective device.
1.1. In order to determine K, an approach speed of 1600 mm/s shall be used for light curtains arranged horizontally. For the light curtains arranged vertically, an approach speed of 2000 mm/s shall be used if the minimum distance is equal to or less than 500 mm. An approach speed of 1600 mm/s can be used if the minimum distance is greater than 500 mm.
1.2. The light curtains shall be installed so that its detection area covers the access to the danger zone, with care taken not to provide spaces for the dead zone, i.e. space between the curtain and the body of the machine where a worker may remain undetected.
1.3. In respect to the detection capacity of the light curtain, at least an additional distance C in Table IV shall be used when calculating the minimum distance S.
TABLE IV – Additional distance C
| Detection capacity mm |
Additional distance C mm |
| ≤ 14 > 14 ≤ 20 > 20 ≤ 30 |
0 80 130 |
| > 30 ≤ 40 > 40 |
240 850 |
1.4. Other light curtain installation characteristics, such as a parallel approach, approach in angle and dual-position equipment shall meet the specific conditions provided in ISO 13855. The light curtain application in hydraulic press brakes shall meet EN 12622.
Source: ISO 13855, Safety of machinery – The positioning of protective equipment in respect of approach speeds of parts of the human body.
C) Requirements for the use of optoelectronic laser presence detectors – AOPD in hydraulic press brakes.
1. The hydraulic press brakes can have an AOPD multiple laser beams provided that accompanied by a detailed work procedure that meets the manufacturer’s recommendations, EN 12622 and the tests provided in this Annex.
1.1. The tests shall be performed by the worker in charge of maintenance or by tool exchange and repeated by the operator himself/herself for each tool exchange or any maintenance, and performed by the operator at the beginning of each work shift and prolonged removal from the machines.
1.2. The tests shall be performed with a test gauge provided by the AOPD laser device manufacturer, which consists of a piece of plastic with sections of certain dimensions for this purpose, according to Figure 3.
1.3. Testing system in hydraulic press brakes equipped with optoelectronic laser presence detector:
a) Test 1: Verify the detection capacity between the tool tip and the laser beam – the closest to the tool. The space shall be ≤ 14 mm (less than or equal to fourteen millimeters) throughout the area of the tool. The test shall be performed with a handle – cylindrical part with 14 mm (fourteen millimeters) of diameter of the test gauge, as shown in Figure 3;
b) Test 2: The section of 10 mm (ten millimeters) in thickness of the test gauge placed on the matrix – the lower part of the tool – shall not be touched during the descending course of the tool. In addition, the section of 15 mm (fifteen millimeters) in thickness of the test gauge shall pass between the tools;
c) Test 3: The section of 35 mm (thirty five millimeters) in thickness of the test gauge placed on the matrix – the lower part of the tool – shall not be touched during the high-speed descending course of the hammer.
Figure 3 – Test gauge
Symbol: 1: handle
2. On hydraulic press brakes equipped with AOPD laser that uses a foot switch to actuate descending movement, it shall be of safe and have the following positions:
a) 1st (first) position = stop;
b) 2nd (second) position = operate; and
c) 3rd (third) position = stop in case of emergency.
2.1. The opening of the tool can be activated, provided that the risk of falling product in process is controlled, with actuation of foot switsch to the 3rd (third) position or releasing it to the 1st (first) position.
2.2. After the activation of the actuator to the 3rd (third) position, the restart is only possible after releasing the actuator to the 1st (first) position. The 3rd (third) position can be actuated through a pressure point; the required force shall not exceed 350 N (three hundred and fifty Newtons).
Source: EN 12622 – Safety of machine tools – Hydraulic press brakes
