BS 4309:1968

This standard BS 4309:1968 Methods of measuring the performance of laboratory electric resistance furnaces is classified in these ICS categories:

• 25.180.10 Electric furnaces
• 71.040.10 Chemical laboratories. Laboratory equipment

This British Standard defines the important performance characteristics of general purpose laboratory electric resistance furnaces of box or tube form (the latter for use either horizontally or vertically) with exposed or concealed heating elements, and recommends appropriate methods of measuring these characteristics.

The standard is intended to apply to furnaces with rating up to about 8 kW and maximum temperature not exceeding 1 600 °C.

The tests are primarily intended for the following:

1. Furnaces with atmospheres of air (they may, however, be applied to furnaces with other atmospheres, e.g. reducing atmospheres, where appropriate).
2. Furnaces with static atmospheres or mechanical re-circulation.
3. Furnaces fitted with control devices, either as supplied or fitted for the purpose of the tests only (see Clause 3).

NOTE It should be understood that this British Standard does not specify any type of furnace as to its performance or safety; or in any other way. It would thus be meaningless to state that a furnace “complies with the requirements of BS 4309”, and such a form of words should not be used.

Definitions of performance characteristics of general purpose laboratory electric resistance furnaces. Methods of measuring these characteristics.