The following suggestions are from a project by William Lull, a principal at Garrison/Lull in Princeton Junction, New Jersey, to help the New York State Division of Library Development create guidelines for improving environments in libraries, archives and similar institutions. Some of the tips may not be advisable, applicable, or feasible for your institution. Please consult a conservator about the relative value of the measures you choose to undertake.
- Keep winter heat low: If overheating occurs, don't allow windows to be opened — demand that the heat be turned down. Open windows and leaky doors allow outside air in, and allow desirable winter humidity to escape. Keep a few sweaters and blankets for staff or visitors who feel cold with the temperature around 65øF, and explain why you're keeping things cool. A small exhibit of damaged paper may help convince visitors.
- Seal windows: Use plastic sheets and tape to seal windows on the inside in winter. In storage areas, line windows with aluminum foil, and seal them more completely with gypsum wallboard and plastic. The foil will reflect sun away to reduce heat in summer, and will also keep light out of the storage areas.
- Keep outside doors and windows closed: Weatherstrip doors, and make sure doors and windows stay closed to prevent exchange of unconditioned outside air. Test seals; if a strip of paper waves in the breeze when it's held up to a crack, the seal isn't tight.
- Block radiant heat from radiators: If you can't move collections well away from radiators in storage or exhibit spaces, cover wallboard with reflective foil and position this barrier between radiators and collections to protect objects from "line-of-sight" heat transmission.
- Keep equipment at one level 24 hours a day: Don't change settings on climate equipment for nights or weekends, since damaging humidity fluctuations usually result. This includes both heat and window air conditioners. Be sure humidifiers or dehumidifiers are on, and that they're always adequately filled (or emptied) to maintain steady conditions. Choose a lower constant humidifier setting to prevent it from running out of water, or raise the constant RH setting on your dehumidifier so it will not overflow or shut off from too much water. (Of course this does not apply to equipment with piped water supplies or drains.) While improving the stability of conditions 24 hours a day usually requires little or no capital investment, using the equipment you have continuously almost always increases annual energy costs. Keep in mind that some of the most acute short-term damage to collections is caused by discontinuous operation of climate control equipment.
- Separate collections that need special conditions: Use available spaces the best way: Look at the available storage areas. Can you modify your use of space to suit the collections better? Are some spaces more stable than others? Do some materials in your collections (like parchment or vellum) need different conditions from others? Can these be segregated into groups with similar needs? This may reduce the need for new or improved conservation environments.