page_title: Smoke screen
section_title: Dyes
hierarchical_section_title: Smoke screen / Chemicals used / Dyes
caption_attribution_description: English: An M18 smoke hand grenade is activated by U.S. Marines from Lima Company, 3rd Battalion, 3rd Marine Regiment at the U.S. Army's Schofield Barracks' military operations on urban terrain facility, Oahu, Hawaii, May 17. The Marines train in preparation for an upcoming deployment in support of Operation Enduring Freedom.
context_page_description: A smoke screen is smoke released to mask the movement or location of military units such as infantry, tanks, aircraft or ships.
  Smoke screens are commonly deployed either by a canister or generated by a vehicle.
  Whereas smoke screens were originally used to hide movement from enemies' line of sight, modern technology means that they are now also available in new forms; they can screen in the infrared as well as visible spectrum of light to prevent detection by infrared sensors or viewers, and they are also available for vehicles in a superdense form used to block laser beams of enemy target designators or range finders.
context_section_description: Various signalling purposes require the use of colored smoke. The smoke created is a fine mist of dye particles, generated by burning a mixture of one or more dyes with a low-temperature pyrotechnic composition, usually based on potassium chlorate and lactose (also known as milk sugar).
  Colored smoke screen is also possible by adding a colored dye into the fog oil mixture.  Typical white smoke screen uses titanium dioxide (or other white pigment), but other colors are possible by replacing titanium dioxide with another pigment.  When the hot fog oil condenses on contact with air, the pigment particles are suspended along with the oil vapor.  Early smoke screen experiments attempted the use of colored pigment, but found that titanium dioxide was the most light scattering particle known and therefore best for use in obscuring troops and naval vessels.  Colored smoke became primarily used for signaling rather than obscuring. In today's military, smoke grenades are found to be non-cancer causing, unlike the 1950s AN-M8 model.
caption: A coloured smoke grenade in use
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