Yes, Qwik System Flush® is safe to use provided you follow the directions. You should always wear protective eyewear, clothing, and gloves while using Qwik System Flush® and it should only be used in well ventilated areas. Flush from inside the building to the outside of the building, to avoid leaving fumes inside the building.
Do not breathe any brand of chemical flushing agent, refrigerant vapors, industrial cleaners, or even high concentrations of nitrogen if you are pregnant.