When it comes to putting all of this information into practice in your own museum, there are a number of practical things you can do. Consider some of the following measures.
A frequently suggested method of controlling temperature and relative humidity levels is through the use of air-conditioning. In most of the main texts, this refers to a full system of environmental control in which both the temperature and the relative humidity can be set to prescribed limits. These require a substantial investment in both up-front design and installation costs and ongoing running and maintenance costs.
It is worth remembering that most of the systems commonly in use are designed for human comfort and assumed to be required only during the normal operating hours of the building. Systems designed for the protection of collections will require more detailed specifications in the brief to the architect, engineer and builder, and may be required to operate continuously. The actual times of operation will depend on the design of the building. A carefully designed building may only require the system to operate part of the time, while still ensuring optimum conditions. As mentioned at the start of the temperature and relative humidity section, this is a complex area of museum planning and cannot be covered adequately within the scope of this subject.
There are also 'stand alone' type heating and cooling systems available. The drawback with most of the basic models is that they do not reliably deliver stable conditions of relative humidity. They are designed simply for human comfort and can have an adverse effect on collections by either putting excess moisture into the air, as can occur with evaporative systems, or by over drying the air, as can occur with cooling coil systems.
If you have air-conditioning or you are considering installing air-conditioning, as part of your planning processes we recommend you:
The cost of purchasing, operating and maintaining an air-conditioning system is high. If not adequately maintained and operated, it can cause more severe fluctuations in temperature and relative humidity than having no system at all.