1.6 Conceptual and Technical Hierarchies
Fig. 1.1 7. Hierarchical distinction among
analyser. instrument. apparatus and device. and
relationship to the hierarchy of Fig. 1.16
25
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1
Process
1
1 _ _ _ _ _ _ _ _ _ _ _ _ _
_I
,-----------------1
T h .
1
1
ec nlque
1
1- _________________ I
temperature program of a gas chromatograph). Special emphasis in this context
should be placed on the difference between instrument and apparatus, two words
that are often used indifferently - and misleadingly - in practice. The difference
lies in whether or not they can provide analytical information.
Box 1.10
The hierarchy for analyser. instrument. apparatus and device can be illustrated with the following examples:
Type of information
Element ranked
Analytica l
Analyser
Instrument
Operational
Apparatus
Device
Examples
• Analyser for gases (°2, CO2) in blood
• Autoanalyser for C and H in steel
• Balance
• Polarograph
• Mass spectrometer
• Chromatograph (gas, liquid, supercritical
fluid)
• Microwave digester
• Extractor (liquid- liquid, solid-liquid)
• Centrifuge
• Pressure or temperature sensor
• Electronic interface