SPECIAL CAUTIONS TO ENSURE THE SAFE DISPOSAL OF SODIUM-FILLED VALVES : Precautions: Notes

Handling and disposal of sodium-filled exhaust valves requires special care and consideration. Under conditions such as breakage with subsequent contact with water, metal sodium which lines the inner portion of exhaust valve will react violently, forming sodium hydroxide and hydrogen which may result in an explosion. Sodium-filled exhaust valve is identified on the top of its stem as shown in illustration.

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