(2)

the following section B3 is added: ‘B3 PERFORMANCE REQUIREMENTS FOR FOLDABLE ROLL-OVER PROTECTION STRUCTURES 5.1. Scope This Section provides minimum performance and tests requirements for rear mounted foldable ROPS which are raised and/or lowered manually by a standing operator (with or without partial assistance) and locked manually or automatically. 5.2. For the purposes of this section, the following definitions shall apply: 5.2.1. ‘hand-operated foldable ROPS’ is a rear-mounted dual pillar protective structure with hand raising/lowering directly managed by the operator (with or without partial assistance); 5.2.2. ‘automatic foldable ROPS’ is a rear-mounted dual pillar protective structure with full assisted raising/lowering operations; 5.2.3. ‘locking system’ is a device fitted to lock, by hand or automatically, the ROPS in the raised or lowered positions; 5.2.4. ‘grasping area’ is an area defined by the manufacturer as a portion of the ROPS and/or additional handle fitted to the ROPS where the operator is allowed to carry out the raising/lowering operations; 5.2.5. ‘accessible part of the grasping area’ is the area where the ROPS is handled by the operator during the raising/lowering operations; this area shall be defined with regard to the geometric centre of cross sections of the grasping area; 5.2.6. ‘accessible zone’ is the volume where a standing operator can apply a force in order to raise/lower the ROPS; 5.2.7. ‘pinching point’ is a point where parts move in relation to each other or to fixed parts in such a way as may cause persons or certain parts of their bodies to be pinched; 5.2.8. ‘shear point’ is a point where parts move along each other or along other parts in such a way as may cause persons or certain parts of their bodies to be pinched or shorn; 5.2.9. ‘place to stand’ is a place on the tractor platform accessible from the driving position main access with sufficient space for a standing operator. 5.3. Hand-operated foldable ROPS 5.3.1. Prior conditions for the test 5.3.1.1. Grasping area The manual handling shall be done by a standing operator with one or more grasps on grasping area of the roll-bar. The roll-bar can be handled from the ground or from a place to stand on the platform (Figures 7.8a and 7.8b). The operator can handle the roll-bar in parallel with or in front of its trajectory. A multiple step process with multiple operator positions and multiple defined grasping areas is allowed. The grasping area shall be clearly and permanently identified (Figure 7.9). This area has to be designed without sharp edges, sharp angles and rough surfaces likely to cause injury to the operator. This area could be on one or both sides of the tractor and could be a structural part of the roll-bar or additional handles. In this grasping area the manual handling to raise or lower the roll-bar shall not create shearing, pinching or uncontrollable movement hazards to the operator. 5.3.1.2. Accessible zones Three accessible zones with different amount of allowed force are defined with respect to horizontal plane of the ground and the vertical planes tangent to the outer parts of the tractor that limit the position or the displacement of the operator (Figure 7.10). Zone I: comfort zone Zone II: accessible zone without forward leaning of the body Zone III: accessible zone with forward leaning of the body Handling of the roll-bar in parallel with its trajectory The position and the movement of the operator are limited by obstacles. These are parts of the tractor and are defined by vertical planes tangent to the external edges of the obstacle. If the operator needs to move the feet during the manual handling of the roll-bar a displacement is allowed either within a parallel plane to the roll-bar trajectory or within just one more parallel plane to the previous one so as to overcome an obstacle. The overall displacement shall be considered as a combination of straight lines parallel and perpendicular to the roll-bar trajectory. A perpendicular displacement is accepted provided that the operator comes closer to the roll-bar. The accessible area shall be considered as the envelope of the different accessible zones (Figure 7.11). Handling of the roll-bar in front of its trajectory: Only for handling of the roll-bar in front of its trajectory are considered as accessible extensions of the zone II and zone III (Figure 7.12). In these extensions the acceptable actuation forces are the same ones as respectively in zone II and in the zone III. If the operator needs to move during the manual handling of the roll-bar it must be done so by a displacement without any obstacle within a plane parallel to the roll-bar trajectory. In this case the accessible area shall be considered as the envelope of the different accessible zones. 5.3.1.3. Place to stand Any place to stand on the platform declared by the manufacturer shall be accessible from the main access to the driving position and fulfil the following requirements: — A place provided for standing shall have sufficient space for both of the operator's feet, be flat and have a slip-resistant surface. Depending on the machine configuration, it may consist of two separate surfaces and may use machine components. It shall be positioned so that the operator can maintain stability while carrying out the service required and be on the same height level with a tolerance of ± 50 mm. — Handhold(s) and/or railings shall be provided in order to allow three-point contact. Parts of the machine can be considered to fulfil this requirement. It is considered that a place for standing has sufficient space if its surface is at least a square in cross section of 400 mm per side (Figure 7.13). Alternatively the place to stand requirement may be met by providing sufficient space for one foot on a flat surface and one knee on the seat. 5.3.1.4. Test conditions The tractor must be fitted with tyres having the greatest diameter indicated by the manufacturer and the smallest cross-section for tyres of that diameter. The tyres must be inflated to the pressure recommended for field work. The rear wheels must be set to the narrowest track width; the front wheels must be set as closely as possible to the same track width. If it is possible to have two front track settings which differ equally from the narrowest rear track setting, the wider of these two front track settings must be selected. 5.3.2. Test procedure The aim of the test is to measure the force necessary to raise or lower the roll-bar. The test will be carried out in static condition: no initial movement of the roll-bar. Each measurement of the force necessary to raise or lower the roll-bar shall be made in a direction tangent to the trajectory of the roll-bar and passing through the geometric centre of cross sections of the grasping area. The grasping area is considered accessible when located within the accessible zones or the envelope of different accessible zones (Figure 7.14). The force necessary to raise and lower the roll-bar shall be measured in different points that are within the accessible part of the grasping area (Figure 7.15). The first measure is carried out at the extremity of the accessible part of the grasping area when the roll-bar is fully lowered (Point 1 in Figure 7.15). The second measure is defined according to the position of Point 1 after rotation of the roll-bar up to the point where the perpendicular to the trajectory of the roll-bar is vertical (Point 2 in Figure 7.15). The third measure is carried out after rotation of the roll-bar up to the top of the accessible part of the grasping area (Point 3 in Figure 7.15). If in this third measure the roll-bar is not fully raised, a point shall be measured at the extremity of the accessible part of the grasping area when the roll bar is fully raised (Point 4 in Figure 7.15). If between point 1 and point 3 the trajectory of extremity of the accessible part of the grasping area crosses the limit between Zone I and Zone II an additional measurement shall be made at this point (Figure 7.16). The maximum forces in these points shall not exceed the acceptable force of the zone (I, II or III). In order to measure the force in the required points, it is possible either to measure directly the value or to measure the torque needed to raise or lower the roll-bar so as to calculate the force. 5.3.3. Condition of acceptance 5.3.3.1. Force requirement The force acceptable for the actuation of the ROPS depends on the accessible zone as shown in Table 7.2. Table 7.2 Allowed forces Zone I II III Acceptable force (N) 100 75 50 An increase of no more than 25 % of these acceptable forces is allowed when the roll-bar is fully lowered and fully raised. An increase of no more than 25 % of these acceptable forces is allowed if the roll-bar is handled in front of its trajectory. An increase of no more than 50 % of these acceptable forces is allowed in the lowering operation. 5.3.3.2. Additional requirements The manual handling to raise or lower the roll-bar shall not create shearing, pinching or uncontrollable movement hazards to the operator. A pinching point is not considered dangerous for the operator hands part if in the grasping area the safety distances between the roll-bar and fixed parts of the tractor are no less than 100 mm for hand, wrist, fist and 25 mm for finger (ISO 13854:1996). The safety distances shall be checked with respect to the mode of handling foreseen by the manufacturer in the operator's manual. 5.4. Hand locking system The device fitted to lock the ROPS in the upright/lowered position must be designed: — to be handled by one standing operator and located in one of the accessible zones; — to be hardly separated from the ROPS (for example captive pins as locking pins or retaining pins); — to avoid any confusion in the locking operation (the proper location of the pins shall be indicated); — to avoid unintentional removing or losing of parts. If the devices employed to lock the ROPS in the upright/lowered position are pins they shall be inserted or removed freely. If to do so there is a need to apply a force on the roll-bar this shall comply with the requirements of points 1 and 3 or 4 (see point 5.3). For all other locking devices, they shall be engineered according to an ergonomic approach for what concerns the shape and the force especially avoiding pinching or shearing hazards. 5.5. Preliminary test of automatic locking system An automatic locking system fitted on hand-operated foldable ROPS has to be submitted to a preliminary test before the ROPS strength test. The roll-bar shall be moved from the lower position to the upright locked position and back. These operations correspond to one cycle. 500 cycles shall be completed. This could be done manually or with the use of external energy (hydraulic, pneumatic or electric actuators). In both cases the force shall be applied within a plane parallel to the trajectory of the roll-bar and passing through the grasping area, the angular speed of the roll-bar shall be roughly constant and less than 20 deg/s. After the 500 cycles, the force applied when the roll-bar is in the upright position shall not exceed by more than 50 % the allowed force (Table 7.2). The unlocking of the roll-bar shall be done following the operator manual. After the completion of the 500 cycles there shall be no maintenance or adjustment on the locking system. Note 1: The preliminary test could be applied to automatic foldable ROPS systems as well. The test should be carried out before the ROPS strength test. Note 2: The preliminary test could be carried out by the manufacturer. In such a case the manufacturer shall provide the test station with a certificate stating that the test has been done according the test procedure and that there was no maintenance or adjustment on the locking system after the completion of the 500 cycles. The test station will check the performance of the device with one cycle from the lower position to the upright locked position and back. Figure 7.8 a From the ground Figure 7.8 b From the platform Figure 7.9 Grasping area Grasping area Text of image Figure 7.10 Accessible zones (Dimensions in mm) Top view of the accessible zones Lateral view of the accessible zones Ground Text of image Figure 7.11 Envelope of the accessible zones (Dimensions in mm) Displacement with one change of directions Displacement without change of directions Obstacle Obstacle Text of image Figure 7.12 Handling of the roll-bar in front of its trajectory. Accessible zones (Dimensions in mm) Text of image Figure 7.13 Place to stand on the platform. Figure 7.14 Example of accessible part of a grasping area Accessible zones Trajectory of the grasping area Accessible part of the grasping area Figure 7.15 Points where the force requirement shall be controlled Point 1 Point 2 Point 3 Point 4 Figure 7.16 Additional point where the force requirement shall be controlled Additional point Point 1 Point 2 Point 3 Point 4 ’;