Under what condition is the industrial hydrazine/morpholine lay-up considered lost?

The industrial hydrazine/morpholine lay-up is considered lost when the hydrazine concentration falls below 10 ppm because this threshold is critical for maintaining the effectiveness of the lay-up solution. Hydrazine serves as a corrosion inhibitor by reducing oxidation and preventing rust and other forms of corrosion in metal systems. If the concentration of hydrazine falls below this specific level, it can no longer provide its protective qualities, thus compromising the integrity of the equipment or system it is intended to safeguard.

Maintaining the appropriate concentration ensures that the preventative measures are effective; when the concentration drops below the required level, it signifies that the protective barrier is no longer adequate, resulting in a loss of the lay-up state. This condition is particularly crucial for systems that are at risk of corrosion during periods of inactivity, and the dilution of hydrazine could be caused by various factors, including the introduction of water or other contaminants.