Conservation of the Shroud of Turin

The conservation-restoration of the Shroud of Turin refers to the conservation-restoration and enduring preservation of the Shroud of Turin to avoid further damage and contamination. Since 1578 the Shroud is kept in the Royal Chapel of Turin Cathedral (from 1694 to 1993 the Shroud rested in the Royal Chapel's Bertola altar), under the laminated bulletproof glass of the airtight case. The temperature and humidity controlled-case is filled with argon (99.5%) and oxygen (0.5%) to prevent chemical changes, the Shroud itself is kept on an aluminum support sliding on runners and stored flat within the case.

When the Shroud is not on public display, the case is closed; during the public display the case can be moved, raised and opened. During the last centuries, the Shroud has been publicly exhibited a limited number of times, often on very special occasions.

On 4 December 1532 the Shroud sustained a fire, which burned out several holes in the fabric. In the spring of 1534 the Poor Clare Nuns patched the holes and placed a backing Holland cloth on the reverse.

On 11 April 1997, the Turin Cathedral sustained another fire, but the Shroud survived entirely unscathed. By that time the Shroud stayed within the three walls of plate glass each 11 feet (3.4 m) long and 6.5 feet (2.0 m) high. The fireman Mario Trematore decided to use a sledgehammer against the bulletproof glass to rescue the relic. Eventually he caused the 39mm thick material to shatter and another fireman arrived to help Trematore. When asked how he managed to break the glass, Trematore replied: "The bulletproof glass can stop bullets, but it cannot stop the strength of values represented by the symbol inside it. With only a hammer and our hands (still bleeding), we broke the glass".

During the 2002 restoration, conducted by the Commission for the Conservation of the Shroud between 20 June and 22 July, thirty triangular patches, sewn by nuns in 1534, as well as the Holland cloth, were removed. The pre-1516/pre-1192 L-shaped burn holes, called "poker holes" and mentioned in the 12th century Hungarian Pray Codex, have remained. The 2002 restoration has been criticized for the damage it caused to the Shroud.

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Wikipedia