Gentek 3940222 Support, Vibration and Movement Requirements, Temperature Variation Requirements

Chapter 2: Prerequisites

Support, Vibration and Movement

Requirements

At a minimum, the supporting structure usually consists of a base cabinet and chemical-resistant work surface.

The ability for analytical balances to accommodate vibration varies with type and brand. More advanced balances have improved tolerance, however in the preparation of a balance enclosure site, please consider the following:

•Avoid tubular stands or mobile benches that have the potential of moving when touched.

•Work surfaces should be of a thick rigid material that remains stable when buttons are pressed. An epoxy benchtop or accessory work surface is a minimum requirement.

•A bench that is rigidly mounted to the floor or fixed to the wall, but not both, may be appropriate.

•The corners of a building typically have less vibration than the center.

•The bench with the balance enclosure should not contain any vibration-producing equipment, such as shakers or pumps.

•Marble, granite or epoxy balance tables are generally recommended by the manufacturers of analytical and microbalances. (See the installation instructions in Chapter 3).

•Marble slabs with dampening pads placed within the enclosure are also an effective low cost means of controlling vibration.

Temperature Variation

Requirements

The extent the balance readings are influenced by temperature variations is a function of the balance design. Most manufacturers would suggest that a temperature drift of 1-2°C is generally tolerable. Only validation through your Operational Qualification protocol can define what is acceptable. To minimize the potential for temperature variations:

•Never install balances near heating sources such as radiators and hot plates.

•Do not place the balance and enclosure on a bench that would receive direct sunlight.

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