Safety is the state of being "safe" (from French sauf), the condition of being protected from harm or other non-desirable outcomes. Safety can also refer to the control of recognized hazards in order to achieve an acceptable level of risk.
Now, it is true that the nature of society is to create, among its citizens, an illusion of safety; but it is also absolutely true that the safety is always necessarily an illusion. Artists are here to disturb the peace.
James Baldwin "An interview with James Baldwin" (1961)
Rotorcraft engines are becoming more electric for greater efficiency and safety. Powering these electrical systems with waste heat conversion will ensure sustainability.