BS EN ISO 4254‑6:2020 pdf download.Agricultural machinery – Safety.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 4254‑1:2013, Agricultural machinery — Safety — Part 1: General requirements
ISO 5681, Equipment for crop protection — Vocabulary
ISO 12100:2010, Safety of machinery — General principles for design — Risk assessment and risk reduction
ISO 13857:2019, Safety of machinery — Safety distances to prevent hazard zones being reached by upper and lower limbs
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4254-1, ISO 5681 and
ISO 12100 apply.
4.4.2 Powered height adjustment
In the case of powered height adjustment systems that are manually actuated, it shall be possible to actuate the manual control from the driver's position and the control shall be of the hold‑to‑run type.
In the case of powered height adjustment systems that are automatically actuated, it shall be possible to override the system from the driver's position.
To ensure the protection of the operator against crushing and shearing hazards related to a failure of the control circuit of the height adjustment of the boom, the machine shall be fitted for those purposes with either:
a) a device which limits the maximum downward speed of the boom to 10 mm⋅s −1 (measured at the centreline of the machine) during a hydraulic failure, or
b) a device capable of stopping the boom lowering at a minimum height of 500 mm between the boom and the ground.
For b), in those cases where the height needs to be reduced to less than 500 mm, a safety device shall prevent any lowering beneath 500 mm without an intentional and separate action of a safety device.
If these safety devices are hydraulic valves not directly fitted to the cylinder, the lines connecting the valve to the cylinder shall be designed to withstand a pressure of at least four times the rated maximum hydraulic pressure.
4.5 Spray tank
4.5.1 Prevention of whole‑body access to the tank
To limit the risk of access into the tank, any tank opening greater than 400 mm in diameter — or, if it is rectangular, of more than 400 mm × 300 mm — shall be provided with a grating which can only be removed by the use of tools. The openings in the grating shall not exceed the above‑mentioned
dimensions. See also 6.1 g) and h) and 6.2.2.
4.5.2 Limitation of contact with chemicals
4.5.2.1 To minimize the risk of exposure to chemicals during filling/cleaning operations 4.5.2.2, 4.5.2.3 or 4.5.2.4 shall be applied.
4.5.2.2 Chemical induction bowls which are folded/unfolded manually shall be provided with a handle and locking mechanism for folding/unfolding that can be actuated without presenting a risk to the operator during operation. The handle can be an integral part of the chemical induction bowl provided it is suitably designed and clearly identified.BS EN ISO 4254‑6 pdf download.