Bank vault

Modern bank vaults are typically made of reinforced concrete and steel, with complex locking mechanisms and security systems.

Unlike safes, vaults are an integral part of the building within which they are built, using armored walls and a tightly fashioned door closed with a complex lock.

They are also common in other buildings where valuables are kept such as post offices, grand hotels, rare book libraries and certain government ministries.

Modern vaults are typically constructed using steel-reinforced modular concrete panels engineered for maximum strength and crush resistance.

The most famous is the Teikoku Bank in Hiroshima whose two Mosler Safe Company vaults survived the atomic blast with all contents intact.

Round vault doors were popular in the early 20th century and are iconic images for a bank's high security.

The lock is invariably mounted on the inside (behind) of the difficult-to-penetrate door and is usually very modest in size and strength, but very difficult to gain access to from the outside.

There are many types of lock mechanisms in use: Quality control for much of the world's vault industry is overseen by Underwriters Laboratories, Inc. (UL) in Northbrook, Illinois.

[13] The testing regime is covered under the auspices of Euronorm 1143-1:2012 (also known as BS EN 1143-1: 2012),[14] which can be purchased from approved European standards agencies.

[15][16] Key points include: Bank vault technology changed rapidly in the 1980s and 1990s with the development of improved concrete material.

Bank burglaries are also no longer the substantial problem they were in the late 19th century up through the 1930s, but vault makers continue to alter their products to counter new break-in methods.