Arc Flash Boundary (ARC) - is the distance at which an electrical arc can flash. outward, which may endanger employees working on electrical equipment. Flash Protection Boundary (FPB) - theJcalculated safe working distance from. electrical equipment which would not expose the employee to the hazards.
One advantage of freeze drying is that food preserved in this method can last longer than food preserved in virtually any other way. Freeze dried foods, if stored properly, can last for years, even decades, and taste exactly as they did the day they were bought fresh.
The product to be dried is frozen under atmospheric pressure. Then, in an initial drying phase referred to as primary drying, the water (in form of ice) is removed by sublimation; in the second phase, called secondary drying, it is removed by desorption. Freeze drying is carried out under vacuum [20].