- (chemistry) Water in its standard form of H2O, containing two protium hydrogen atoms, as opposed to heavy water.
- Foam formed by water and a fluorocarbon surfactant, used in firefighting because it floats on flammable liquids lighter than water.
2001, Roger C. Mardon, An Illustrated History of Fire Engines, ↑ISBN, page 112:
- The light water (AFFF) of the TACR was to be backed up by fluorinated protein ioam instead ot standard protein foam.
2014, John R. Ridley, Safety at Work, ↑ISBN, page 504:
- These fires can be extinguished with water spray, alcohol-resistant foam, light water, vaporising liquids ("Halons'), carbon dioxide and dry powder.
2015, Phil Hughes & Ed Ferrett, Introduction to Health and Safety at Work, ↑ISBN:
- They can be extinguished by carbon dioxide, dry powder, water spray, light water and vaporising liquid