InfraCal 2 ATR-SP Frequently Asked Questions

Instrument Specifications

What is the LOD of the InfraCal 2 ATR-SP?
The InfraCal 2 ATR-SP has a minimum detection limit of 0.3 ppm for oil in water and 3 ppm for oil in soil.

What is the highest range of measurement for the ATR-SP?
The InfraCal 2 ATR-SP can be calibrated to measure up to 15% oil in water or soil.


How long does the calibration last?
A calibration lasts anywhere between one year and many years depending on frequency of use and environment.
We recommend you do an annual calibration verification and recalibrate when necessary.
Can you make your own standards?
Yes.  Instructions are in the manual, Appendix B, Calibration Standard Preparation

Why do the standards read differently than the value on the label?
If the instrument is calibrated for a 10:1 extraction, the standard will read approximately a factor of 10 lower than the labeled value of the standard.  For example, a standard labeled 500 ppm will read 50 ppm.  For instruments calibrated for a 1:1 extraction, the instrument will read approximately the labeled value of the standard. 

The Analysis

Which solvents can be used with the ATR-SP?
The most common solvents used with the InfraCal 2 ATR-SP are Hexane and Pentane.  However, the ATR-SP can be used with any volatile hydrocarbon solvent with low evaporation residue.

How much solvent do you need for an analysis?
The required amount of solvent is dependent on the measurement range.  For calibrations using a 10:1 extraction ratio the measurement typically requires 10 – 25 ml of solvent depending on the sample size.  For calibrations using a 1:1 extraction ratio the measurement typically requires 25  - 100 ml of solvent depending on the sample size.

How long can you wait in between sample collection and analysis?
You can wait several days after sample collection before measuring the sample.  If the sample is not to be measured within a few hours, you MUST acidify the sample to a pH of 2 using HCl or Sulfuric Acid.

Instrument Features

Can the instrument connect to a printer? 
No.  Results many be transferred to a computer for printing.

Can the instrument connect to LIMS? 
No.  The InfraCal 2 software does not allow for connection to LIMS.

How long does the battery last? 
A new, fully charged battery should last approximately 6 hours.

How many measurements does the instrument store? 
The instrument can store up to 2,000 results.

Instrument Maintenance

Is the instrument sensitive to temperature?
For high precision measurements (below 10 ppm) it is recommended the instrument be used in a temperature controlled environment.  Less precise measurements are not as sensitive to temperature, however, the instrument should not be placed near a heating or cooling source.

Does the Instrument require any special maintenance?
No.  We recommend keeping the instrument clean and dry.  A plastic dust cover is supplied with the instrument.

How do you clean the sample trough?
Using a lint-free, non-abrasive cloth and solvent, wipe in one direction.  Repeat with isopropyl alcohol.  For more specific instructions, refer to the manual.

How long does the source last?
The InfraCal 2 ATR-SP source has a typical life span of 5+ years.  

Do you turn the instrument off when not in use?
If you are continuously using the instrument it is not necessary to turn the instrument off as there is a required minimum 30 minute warm time.  If you are not going to use the instrument regularly we recommend turning the instrument off. 

Instrument Service

How do you run and interpret diagnostics on the instrument?
Refer to the section of the ATR-SP Manual  Accessing Diagnostic Screens for this information.  Please contact our Customer Support Department with the information obtained from your diagnostics.

Can the source be replaced in the field?
Yes.  We can provide you with resources on the process of changing a source, however, once you begin a field repair Spectro Scientific is no longer responsible for further damage to the instrument that may occur during the replacement.  

Can you change the filter location?
The IR filter used in the InfraCal 2 TRANS-SP is centered at approximately 3.44 um and typically detects IR absorption from 3.35 um to 3.55 um. This filter location cannot be changed.


Can I measure the extract if the solvent layer looks cloudy?
If the solvent layer of the extraction looks cloudy or contains significant emulsion, it is recommended that solvent emulsion breaking techniques are applied to the solvent layer before continuing.  Refer to the section in the manual, Appendix C, Emulsion Breaking Techniques

Can I use a syringe different from the one provided?
It is recommended only using the syringe provided with the instrument as it is critical the 60 µl measurement of sample is precise.  Other syringes or pipettes may not provide enough accuracy for this analysis.