The World's longest tunnel page - Fire accidents in road tunnels

• 29entries listed
• 1949–2007openings span
• 130.89 kmtotal length

The record table

How this archive measures: lengths, bores, dates and ordering

How this table is compiled

9 of the 29 measured entries exceed five kilometres, and those are the ones that carry a full ventilation and escape regime. Laid end to end the entries on this page would run 130.89 km, which is a number with no engineering meaning but a useful sense of the scale of what is catalogued.

The route table lists 29 structures with a recorded length, giving both carriageways where the two bores differ. The material on this page is held in 33 captions rather than in running text, 288 words of it, each written against the image or row it belongs to by the compiler who put the page together.

Dated entries run from 1949 to 2007, and the busiest decade is the 1990s with 9 recorded openings. They are not uniform: the fullest runs to 18 words and the briefest to 6, and on a page of this kind the long ones are where the explanation lives — the caption carries what the picture cannot.

The three longest entries alone account for 41.41 km of the 130.89 km on this page, which is 32 per cent of the total from 3 of 29 rows. The shorter half of the table totals 14.53 km against 116.36 km for the longer half, from the same number of rows.

5 entries reach ten kilometres and 0 reach twenty, a distribution that decides how much of this table needs full mechanical ventilation. Only 15 of the 31 rows carry anything in the duration of fire column, so that field describes a minority of this table and the rest of the rows are recorded without it.

Reading the figures

Lengths for the world are recorded in metres which is how the operators publish them and why the shortest entry here reads as 148 m and not a rounded figure. 3 of the 29 entries fall within a quarter of the median length, which is how tightly this particular list clusters around its typical structure.

After the 1990s the next busiest decade here is the 2000s with 9 openings, so the building effort came in more than one wave. The year column names 29 distinct entries on this page, 1982 3. Nov. and 1995 10. April among them, each traceable to the operator or administration record it was taken from.

Between the longest and the tenth-longest the drop is 12.12 km, which is the part of the table that changes when a single scheme opens. The ten longest average 9.73 km against 1.77 km for everything below them, and that ratio is the clearest thing this table says about the distribution.

The table on this page runs to 31 rows and records Year, TUNNEL Length, Location Country, Vehicle where fire occurred and Most possible cause of fire for each of them, which is the shape the original compiler chose rather than one imposed here. Traffic figures are deliberately excluded, since they date far faster than the structures themselves.

The longest entry is 114.3 times the shortest and 6.3 times the median, which is the quickest measure of how uneven the table is. The dated entries fall across 22 different years, which is a rough measure of whether this was a sustained programme or a handful of separate schemes.