ANSI B175.4-2018 pdf download.Portable, Handheld, Internal Combustion Engine-Powered Cut-Off Machines – Safety and Environmental Requirements
4.3. Engine stopping device
The engine shall be fitted with an on/off or stop control, which brings it to a final stop and does not depend on sustained manual effort for its operation. This device shall be positioned so that it can be operated while the machine is being held with both hands by the operator wearing protective gloves. The purpose and method of operation of the device shall be marked clearly and durably. The color of the stopping device shall clearly contrast with the background.
4.4. Throttle control and lockout
The cut-off machine shall be equipped with a continuous-pressure throttle control system that will discontinue the power to the cut-off wheel when pressure is released.
4.4.1. Requirements
A throttle control lockout shall be provided, and it shall be constructed so that it must be actuated before the throttle control can be activated. When the throttle control system is locked out, the throttle control valve shall be in the idle position unless a throttle control latch is engaged (for starting). The throttle control lockout shall not prevent the engine from returning to idle speed. The cutting wheel shall not engage or move when a force is applied to the throttle control without releasing the throttle control lockout.
4.4.2. Test Procedure
The throttle control lockout function shall be verified by applying a force equal to 50 N ± 2 N (11.24 lbf ± 0.45 lbf) or half the dry weight of the machine (without accessories and/or cut-off wheel), whichever is higher, on the throttle control with the throttle control lockout engaged. During the test the handle shall be fixed and shall not contact the throttle control lockout. The force shall be applied gradually to the throttle control in the direction of travel and held for 5 s ± 1 s. The force shall be applied 12.5 mm (0.5 in) from the rear of the throttle control.
A throttle control linkage shall be designed so that a force equal to three times the machine dry weight (without accessories and/or cut-off wheel) applied in any direction to the rear handle shall not increase the engine speed to a point where the clutch engages and the cut-off wheel movement begins.
4.5. Clutch
The cut-off machine shall have a clutch so designed that the abrasive cut-off wheel does not move when the engine rotates at any speed less than 1.25 times the idle speed specified in the operator’s manual.
4.8.1. Tank filler location and identification
The fuel tank filler opening, and if provided, the oil tank filler opening, shall be located so that access to the filler opening(s) is not unduly obstructed by other cut-off machine components. Each cap or opening shall be clearly and durably identified. If only the caps are identified, they shall not be interchangeable.
4.8.2. Tank filler openings
The minimum diameter of the fuel tank filler hole shall be 20 mm (0.80 in). The minimum diameter of the oil tank filler hole, if provided, shall be 15 mm (0.60 in). The design of the caps shall be such that no leakage occurs while the unit is being used at normal operating temperature, in each of the six orthogonal directions, and while being transported. Each cap shall have a retainer that prevents separation from the cut-off machine. Evaporation through the fuel cap ventilation system, if equipped, is not regarded as leaking.
4.8.3. Fuel feed line integrity
The fuel feed lines used in the unit shall be resistant to fuels, oils and environments expected for use by the manufacturer, as described in the operator’s manual. The lines shall be evaluated according to Annex A. Fuel feed lines shall be routed so that they are not subject to direct abrasion when located outside of the tank.ANSI B175.4-2018 pdf download
