A common mistake in industry is the miscommunication of colour data. Individuals in a supply chain think they are talking in the same "colour language" but, in fact, are not.
For example: Delta E values can be calculated for CIE L*a*b*, Hunter LAB, CIE L*c*h, CMC and CIE 94.

It is rather like an architect talking Metres, whilst the builder thinks the unit of measurement is Feet or Yards. Result? Disaster.
The following simple steps should minimise the chance of monumental miscommunication:
- State 'illuminant' or 'illuminants' (primary, secondary or tertiary) used (eg. D65, A, CWF).
- State 'degree observer' (2 degrees or 10 degrees)
- State 'colour equation used' (eg. CIE L*a*b*, Hunter LAB, CIE L*c*h, CMC or CIE94).
- State model and manufacturer of instrument used.
- State 'tolerances', if applicable.

As with any scientific instrument, you should always ensure that your spectrophotometer has a valid calibration certificate.