EN 1829-1-2010 pdf download.High pressure water jet machines-Safety requirements-Part 1 Machines.
5.2.2 Safety devices against exceeding the pressure
The machine shall have a safety device which prevents the maximum allowable working pressure from being exceeded by more than 15 % or in the case of machines with pulsation dampers by more than 10 %. It shall not be possible to switch off this safety device and it shall be designed arid positioned in such a way that it cannot be made inoperative.
The adjustment of the safety device shall be secured such that unauthorised changes are deterred by means such as a seal or tamperproof device. The water that escapes through a safety device shall be capable of being drained in a safe manner. This may be executed by the use of a by-pass-system or catch basin or compartment.
Safety devices shall be designed and positioned in such a way that persons cannot be injured by escaping water or by broken pieces.
5.2.3 Pressure Indicator
The machine shall have a pressure indicator which directly displays the actual operating pressure of the liquid at the outlet of the pressure generator in megapascals (MPa) or bars (bar). The display shall be readily visible to an operator and the maximum allowable working pressure shall be marked.
The pressure indicator shall be designed and positioned In such a way that, in case of leakage, persons cannot be injured by the escaping water or by broken pieces.
5.3 Mechanical requirements
5.3.1 Common requirements
All parts of the pressure system shall be designed to withstand the maximum allowable working pressure specified by the manufacturer. The test pressure shall be related by a factor to the maximum allowable working pressure which is given in the manufacturers specification. In no case shall this factor be less than 1,3.
5.3.2 Spraying devices
5.3.2.1 Common requirements for spraying devices
Spraying devices shall be able to withstand the impact and shock stresses which can be expected during normal operation without displaying any leakage or limitation of the intended function.
The activation mechanism shall be protected against unintended activation (e.g. by a guard).
5.3.2.2 Hand-held spraying devices
When the activation mechanism is released one of the following shall occur:
a) No more liquid shall emerge from the nozzle (dry shut-off).
b) Any liquid emerging from the spraying device shall generate a reaction force no greater than the weight of the spraying device.
c) The pressure generator shall be switched off. The safety related parts of the control system shall present a performance level of at least c, defined in accordance with EN ISO 13849-1.
The release of the activation mechanism shall not be impaired or made impossible by recoil effects during shutting-off. The holding force that has to be exerted manually on the activation mechanism of the spraying device shall not exceed 60 N for the whole hand.
The activation mechanism shall be lockable in the OFF-position. This can be achieved e.g. by a knob. hand lever or switch. There shall be no provision to lock the activation mechanism in the ON-position.
The recoil forces exerted on the spraying device shall not exceed 250 N in the longitudinal direction. The recoil forces shall not be released within a period shorter than I s to allow time for the operator to react.
When several spraying devices are connected to the same pressure generator, the recoil forces exerted on the other spraying devices shall not change abruptly by more than 15 % at any time that an operating element of another spraying device is activated.
If the length of the spraying device is less than 75 cm, the activation mechanism shall be designed as a two handed device such that the spraying device can only be run by simultaneous activation of both activation devices, which shall be mounted in a way that makes activation by one hand impossible. The Instruction Handbook shall include a warning of the increased hazards of using short spraying devices (see 7.1). The spraying device shall be equipped with a support (see Figure 1) to which the recoil force is completely or partially transferred if the recoil force is greater than 150 N in the longitudinal direction (Fcos a in Figure 2). This support shall fulfil basic requirements in regard to occupational safety and health aspects as specified In EN 614-1. Radial recoil forces resulting from a nozzle at an angle a and a distance I between the nozzle and holding position creating a torque T = F x sin a x I shall be compensated for, e.g. by a compensating jet.EN 1829-1-2010 pdf download.