Fireproofing

An item classed as fireproof is resistant in specified circumstances, and may burn or be rendered inoperable by fire exceeding the intensity or duration that it is designed to withstand.

Lightweight polystyrene beads may be mixed into the plasters at the factory in an effort to reduce the density, which generally results in a more effective insulation at a lower cost.

An alternative method to keep building steel temperature below the critical strength limit is to use liquid convection cooling in hollow structural members.

[citation needed] In ordinary building fires, concrete typically achieves excellent fire-resistance ratings, unless it is too wet, which can cause it to crack and explode.

[11] Fireproof vaults to protect important paper documents are usually built using concrete or masonry blocks as the primary building material.

[citation needed] In the event of a fire, the chemically-bound water within the concrete or masonry blocks is forced into the vault chamber as steam, which soaks the paper documents to keep them from igniting.

[citation needed] This steam also helps keep the temperature inside the vault chamber below the critical 176.7 °C (350 °F) threshold, which is the point at which information on paper documents is destroyed.

[citation needed] This vault construction method is sufficient for paper documents, but the steam generated by concrete and masonry structures will destroy contents that are more sensitive to heat and moisture.