Page 15 - Customer Needs and Use Assessments (CNUA) of Hydrocardon Sensors

ACT In Situ Hydrocarbon Sensors Customer Needs and Use Assessment.....................................................14
figure, some of these ranges were expressed in context to a particular reference standard
or hydrocarbon class.
8. What level of accuracy do you require for this priority application?
Users (7) had a greater tendency to answer this question non-quantitatively using terms
such as “low” or “best possible” as responses. Of those responses that could be
quantified, ACT normalized and grouped accuracies either as ppb or as percentages
depending on how this question was answered. Accuracy with respect to false negatives
or false positives is the key issue, one colleague noted. This could be expressed or
thought of as reliability of detection.
As ppb:
• 1 states ± 1 ppb
• 5 state ± 10 – 100 ppb
As percentages:
• ± 1 %
• 1% of Full Scale
• If napthalene is used as a standard for a refined fuel sensor, ± 5% of reading or
± 20 ppb, whichever is greater (Vendor).
• 4 state ± 10 %
• 1 states ± 20 % (Vendor)
• Depends on the accuracy of your pipet (Vendor).
• As accurate as the calibration technique (i.e. UV absorption, GC-FID, GC-MS)
you use.
9. Are your current sensors:
[ ] Primarily commercial products
[ ] Primarily designs you developed yourself
[ ] A combination of both
Users:
Ninety-five percent (19) of Users primarily used commercial products. No one designed
their own sensors; however, 10% agree that their sensors are a combination of off-the-
shelf sensors and their own design.
Vendors:
Among the Vendors’ only 29% used commercial products primarily while 14% used
technologies designed by themselves and 57% as hybrids of off-the-shelf sensors and
their own designs.