Conserving Archives

Part of the role of Local History Recorders is to ensure that interesting archives and objects relating to the past of their communities, are retained and looked after. In 2004 the association had an extremely useful workshop on this subject, organised by Lynn Morrison, the Conservator at Saffron Walden Museum. All Recorders have since then been given the following worksheet, a useful check list for others wanting to know how to care for precious documents of the past



Conservation is an ongoing process of learning, you need to know when to leave things alone and when to ask colleagues for advice.Emphasis is on preventive care, storing things properly can do a lot to save material from destruction. Protect objects till you can examine them, then decide if you can deal with it or if it needs someone more experienced. Give yourself space to work. Be aware some objects are harmful, e.g. there could be asbestos, or chemicals could have been applied in the past. If in doubt bring things to Museum to be tested to see if they are harmful to health, and handle with gloves and mask. Inhaling mould is bad for health. Buy dust masks, cotton handling gloves or gloves with a grip from pet shops. A box of 100 disposable plastic gloves costs only a few pounds from dental suppliers. Much free advice and help is available from your local museum.


The aim of conservation is to protect against damp, heat, mould, insects = light, temperature, humidity and pests + to minimise the tendency of some materials to self-destruct over time. Conservation focuses on what objects are and how to preserve it, e.g. metal is complex – each metal is different and needs different treatment.

LIGHT: You need low light levels to avoid fading. You can put a film over the windows to keep ultra violet out, or use blinds, or store in cupboards, boxes and drawers.

TEMPERATURE: Temperatures should be low. Cool storage slows down the rate of decay of most objects. Victorian brick buildings act as a buffer to harmful fluctuations of temperature.

HUMIDITY: Objects react to moisture, expanding and contracting all the time which is why fluctuations cause warping and cracking. Objects can be stable in most conditions but mould grows at high humidity (above 68%), which should be avoided. Relative humidity should be lower for metals, say 40% whereas organics prefer higher humidity, about50-60%.You can never completely get rid of mould and cannot totally exclude air and moisture from affecting your objects. Roof spaces are bad places to keep things due to roof leaks. Cellars are usually too damp. You can use a home dehumidifier, but remember to empty the bucket regularly. Museums use a thermo-hydrograph to give a picture of temperature and humidity in storage space over time. Meters cost several hundred pounds, but hygrometers are cheaper. A whirling hydrometer only costs £20-£40.

PESTS: Vigilance and good housekeeping are the best defence against pests, which are a big problem if left undisturbed – moths, silverfish, invisible book lice. When you get a new object quarantine it and examine carefully. If in doubt, or it is obviously affected, put it in a polythene bag in the freezer – minus 30 degrees for 3 days, or -18 degrees for a week, or -10 degrees for 2 weeks: this kills all stages of the pests and is better than chemicals. Freezing does not damage paper, photos, or even framed pictures.

Rodents – watch out for mice. Moths attack textiles. Woodworm can be seen by piles of powder under undisturbed wood objects, as well as flight holes – the answer is to freeze the objects. Woodlice and spiders don't eat things but they are an indicator of damp, so dry out the environment. Pests like it warm and damp – conditions to avoid.Booklice and silverfish are very bad for paper. Make the stores dry and cool and remember pests thrive in dark, undisturbed conditions, so keep cleaning!


Scanning and photocopying produce lots of light on your object so only do it once. Write on the back of the object in soft pencil that it has been scanned, or keep a written record.

Cleaning: Dry cleaning is best, using a brush. Dust objects with a soft brush directing dust into the nozzle of a vacuum cleaner or use a soft brush attachment with muslin, netting or tights over it to stop bits being vacuumed up. Brush off mould, preferably outside. If necessary to use moistened cloths, use distilled water – a dehumidifier produces distilled water which can be used to wash things.

Photographs: Silvery tinge on photographs indicates deterioration of the silver nitrate in the emulsion – there is no cure, so just photograph or scan it once and don’t exhibit it in the light. Curled up photos should be stored flat which might improve them. Avoid handling by storing photographs in a Melinex sleeve.

Documents: Paper can be flattened by relaxing first in a damp place for a short while, then weighted, then stored in an archival grade Melinex sleeve – don’t iron it and don’t use sellotape. Copies of documents should be treated with the same care as the original. To repair the broken spine of a book, you need a book binder, or else just protect and conserve to prevent further damage. Try enclosing broken items in a Melinex sleeve or tying with soft linen tape.Maps: A brittle map is damaged when you open it, which is why relaxing it first in higher humidity is a good idea. Tears get bigger when it is used, this needs professional conservation using archival grade materials. Rolled maps need protection with a central roll of Jiffy foam or acid free tissue, and foam, tissue paper or cotton around the roll on the outside.

Cataloguing: To avoid going through your documents all the time, catalogue them. Put a location number as well as a document number on the record, since hunting through archives damages them. Card indexes are perfectly good. Store things logically. For cataloguing, use simple names and classify under: Personal, Domestic/Household, Industrial (includes shops etc) or Agriculture.

Marking: It is no good just marking packaging as it may get lost. Mark documents on the back with a soft B pencil. On pottery use a push-nib pen, nail varnish first, then write number, then varnish on top. Tie on a shop label to objects or to tapes enclosing objects e.g. map rolls. For records and packaging use a light-fast, archival quality pen, or pencil, but not biro.


Furniture: Use formica or metal shelves and low-acid archive boxes. Avoid chipboard and MDF due to acidic vapours. Hang big things from the ceiling or walls, using soft linen tapes so you don't mark the objects

Boxes: Ordinary cardboard is very acidic – don't use supermarket boxes. Use acid-free archival boxes - shallow boxes are the most useful, not too big. For odd shapes, make grey card containers or boxes cut to the size needed. Big things need acid free folders too. Correx (used on estate agents' boards) is good to make flat supports or boxes and reasonably inert. Valuable volumes can go in strong card slip cases cut to shape.

Plastic bags: only use polythene and cut a hole on each of the lower corners or punch holes to let the object breathe. Mark outside of bag – look for pens which write on plastic, the nib comes in various thicknesses.Don't use ordinary envelopes – brown ones are acidic, and white are no better. For tubes use jiffy foam rolled up as it is made of polythene.

Photographs: Photo albums – many are no good as the plastic is pvc. The sticky page ones in particular deteriorate as the adhesive is poor quality.Loose leaf albums with archival acid-free sheets cost are expensive. Each photo should go in its own Melinex envelope which contain no harmful chlorides, like pvc does. All these are transparent which aids viewing of the photographs.
Slides and negatives should be kept in archival quality slide packets which you can see through. They have hanging rails for a filing cabinet.

 Packaging: wrap larger objects in acid-free tissue which costs a few pounds per ream. For small objects, use plastazote foam and cut out shapes for the objects to buffer them, then sandwich it and put in polythene box. Use linen tape to tie. Don't use ordinary paperclips, they rust and mark paper. Never use rubber foam as it deteriorates badly.Cheap office products can be a false economy.


Notes copyright: Lynn Morrison, Conservator, Saffron WaldenMuseum