The flame screens installed on tank vents that may contain combustible gases, are designed to prevent explosions by which of the following?

Correct Answer: Option B — dissipating the heat of an external flame

Flame screens utilize a fine wire mesh to dissipate the heat of an external flame. By conducting heat away from the flame front faster than the gas can burn, the screen prevents the flame from propagating through the vent into the tank, thereby protecting the cargo from external ignition sources.