What is the only safe way to use ether in engines?

Using ether in engines presents significant safety risks due to its highly flammable nature and the potential for hazardous vapors. A closed dispensing system is the only safe method for using ether because it minimizes exposure to the substance, thereby reducing the risk of ignition from sparks or open flames. This type of system ensures that ether vapors are contained, eliminating the possibility of accumulation in the surrounding environment, which could lead to explosive conditions.

In contrast, other methods, such as a manual dispensing system or using ether in an open-air environment, are less safe. A manual dispensing system may not adequately control vapor release, while open-air environments do not provide sufficient protection against accidental ignition. Operating without any precautions is particularly dangerous, as this disregards essential safety measures that are critical when handling flammable substances. Thus, the closed dispensing system is designed to provide a safe and controlled environment for handling ether, ensuring that both the user and the environment are protected.