6 members of Sub Brit visited the British Library basements in a visit arranged by Sarah Jenner, who works in the Preservation Department.

We started off at the model in the foyer for a bit of ‘orientation’ - the building was constructed 1982-1997 at a cost of £m 516 as a replacement for and amalgamation of 17 other sites - principally that at the British Museum. Only half the site had been developed in a first phase, of which half was a large open ‘piazza’ fronting the Euston Road. Wholly under this, and extending somewhat under the building, were the basement levels housing plant and book stacks, going down 23m (75ft). It should be noted that the Northern and Victoria lines go east-west under the site. The basements were built downwards under an umbrella slab while the main building was being built upwards on top - the same technique used for Westminster Station/Portcullis House. A second phase, on the north of the main building, The Centre For Conservation, was about to start construction. The BL receives 13 kilometres of legal copyright deposit per year, and the existing stacks were now virtually full - so a new low oxygen depository was also being built in an industrial unit at Boston Spa. We visited a typical book stack floor.

A central ‘retrievals area’ was a loading/unloading station for the automatic crate conveyor system which snaked everywhere through the exposed ceiling void, with points and vertical drops, and red crates trundling magically along, automatically routed to the correct destination anywhere in the building by a bar code and scanner system, where they were loaded onto trolleys for onward dispatch. It actually reminded me of what I presume an ammunition handling system in eg Monkton Farleigh must have been like - the task was the same, to get a 2 foot cube either into storage or out of storage.

Adjoining the retrievals area was a ‘Section Room’ for staff. This was an attractively decorated relaxation area for staff requiring to work underground.

Surrounding both were fire compartments of book stacks, each separated by double roller shutters with fusible links - mainly containing very high capacity rolling shelves. Some areas, for more valuable pre 1850 books, were within locked wire mesh cages, whilst the priceless books were in high security vaults.

Fire protection had originally been planned to be a dry sprinkler system, where the water was held back by a pressurised gas so that when a sprinkler was triggered the gas escaped first providing a delay of a minute or two before the water appeared. Because of this the smoke detectors were at three times the density required by the British Standard, but eventually the delay was held to be unacceptable and a conventional instant wet system was reverted to. The security vaults were controlled to 16-18 degrees C and 40-55 % RH, with an ‘Inergen’ gas fire protection system which was automatically locked off as someone entered.

Also on this floor was an emergency ‘Recovery Area’ for the disaster recovery of water damaged books, with drop down tables, acetate cellular protection and drying fans to stabilise them and a ‘Blast Freezer’ wind tunnel room to take them down to -18 C very quickly. Storage was then in a chiller store at -18 C next door, before freeze drying in a 1 mt diameter x 2mt long vacuum chamber. These facilities have now been replicated in the new Centre For Conservation, where wet book salvage training is carried out; they practiced on Yellow Pages!

We then descended to the lowest accessible level, which was similar to the floor we had seen, but we were intrigued by oblique references to a lower level where no one could go as it was classed as a H&S ‘Confined Space’ full of ‘Foul Water’ and required breathing apparatus and special training to enter, after being forced ventilated for 24 hours. Neither of our guides had been down there and they didn’t know what it was for or how big it was. The Head of Security’s Ultimate Universal Master Key failed to unlock the door. We were only confirmed in our ‘Tube Station to Box and the Strategic Reserve’ supposition. However, perusing the bookshop upstairs afterwards I found in ‘The Design and Construction of the BL’ by the architect Colin St John Wilson, a photograph of a model of the vertical construction. This showed the whole basement was underlain by a half height space above the final lowest concrete slab, presumably in effect a huge sump as an absolute assurance that the lowest stack would be dry.

We then visited the plant rooms. There were 2 ‘small’ plant rooms containing chillers and boilers, and three ‘large’ ones with the A/C plant. The appellations ‘small’ and ‘large’ were relative - the small ones were huge, and the large ones were gargantuan, stretching as far as the eye could see - we had never seen such huge and complex plant rooms, they were truly awesome. Just planning them must have been an heroic task. There were also five 11kv substations (with 110v site power points - a neat reduction factor of 100!), and two LEB substations, one of which had had a flash over and fire.

The Tank Farm was, you guessed it, full of water tanks (unfortunately no one knew the total capacity, but it was big) - dual use for the sprinklers and the domestic water supply to the rest of the building, the sprinklers taking priority. There were no tanks in the roof, the water was all pumped from here. There was a stupendous water softening plant with a salt tank about 4 mt in diameter and 6 mt high which took 14 tons a month.

The standby generator room contained two diesel sets supplied by ‘AutoDiesles’, each consisting of a Dorman 649 HP engine and a Newage Stamford 560KvA generator, starting by 18 Alcad cells. One had done 759 hours and the other 335 hours.

We then exited into the piazza, much to the surprise of the public!

Finally, as a non subterranean bonus, we ascended the lift up the centre of the 6 storey free standing central atrium glass monolith of the King’s Library book stack (the lift, which supposedly took 7, objected after 3). We had the fun of looking down on Emily Wilcox and her mum sitting in the cafe while Tom phoned her on her mobile and said ‘look up!’.

The Centre For Conservation, the first extension to the original building, was started four months after this visit, and opened in 2007. It is 2,600 mt sq and three stories and is accessed from a first floor connecting terrace over the loading bay. This is designed to be incorporated in a proposed ‘Pedway’ connecting King’s Cross, St Pancras International and Euston stations. The main north lit conservation studios and workshops sit on a lower storey of audio studios acoustically isolated on reinforced concrete slabs floating on 600mm thick rubber pads (remember the tube and main lines beneath). Their main remit is audio transfer of archive recordings to digital - for this purpose there is a large collection of obsolete recording machines!

Also since the visit the Midland Road, adjoining the Library on the east, has been excavated for the insertion of the cut-and-cover St Pancras ‘Midland Mainline’ station box, in the process destroying a ‘secret’ stair shaft down to the Midland Curve which used to be accessed from a metal door at the bottom of the St Pancras taxi-ramp - now somewhere in the middle of the new Foyles bookshop!

All in all a very interesting visit - thanks to Sarah Jenner for organising; and Tim Moulton and Roy Alston who conducted us round.