BTEX Monitoring

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PetroSense® (FCI Environmental, Inc.) has been a leader in Total Petroleum Hydrocarbon (TPH) and BTEX monitoring systems for almost twenty years. PetroSentry is the only commercially available system that can detect both the presence and concentration of TPH and BTEX in vapor and dissolved in water on a real time basis in field applications.

We offer both a portable version for on site spot testing PHA 100 Plus and a continuous monitoring version CMS 100 that allows users to monitor remote sites via the internet. The CMS 100 allow one to view all tests sites from any security enabled computer connected to the internet; this system also has the capability to send alarms via text or emails when an incident occurs. PetroSense systems have been used extensively in the by the Above Ground and Underground storage industries for leak detection, the Offshore production industry for monitoring produced water, and the industrial community for monitoring hydrocarbon intrusions in process water.

In addition, we have numerous ground water, aquifer and harbor monitors applications, designed to provide early warning alerts. And more recently, we have installed systems to monitor the impact of fracturing on the underground water sources. If you have a reason to be concerned about hydrocarbon contamination and you are looking for a proven cost effective solution, we would welcome the opportunity to visit with you about your requirements and how PetroSense fits into your solution.

PetroSense sensors operate in air (vapor), water and soil.

PetroSense sensors are non-specific detectors for TPH, semi-volatile hydrocarbons (e.g., diesel fuel, heating fuels, etc.), trichloroethylene/perchloroethylene and many other related compounds. The detection capability of these sensors is unaffected by high humidity, or by naturally occurring methane. PetroSense sensors have been used in a variety of applications:

Although these sensors are non-specific, there is a relative response characteristic for the different compounds that are detected. The PetroSense sensors have a very strong response for aromatic and other large hydrocarbon compounds. This makes these sensors very useful for the detection of BTEX (benzene, toluene, ethyl benzene and xylenes), which is used as a tracer for TPH leaks/contamination. The characteristic relative response factors (RRF's) can be determined for specific sites. The sensors can be calibrated for specific compounds expected at a given site, or the non-specific readings can be converted to the concentrations of these specific compounds by use of the appropriate RRF's.

Word From An Independent Study:

Fiber Optical Sensor (FOCSTM) System – used to directly and quickly monitor concentration of total petroleum hydrocarbons in the air, at the air/water interface, and dissolved in water. FCI's hydrocarbon sensor is designed to monitor the concentration of dissolved BTEX in water, liquid product at the air/water interface , and BTEX in vapor.

PetroSense sensors are very sensitive to BTEX and its individual components dissolved in water. The Sensors are capable of detecting low concentrations of BTEX with a high degree of accuracy. FCI’s sensors match readings taken via the gas chromatograph with at least a 98% correlation." Based on a comparison with EPA Method 8020.



The PetroSense sensors begin to respond immediately to the presence of BTEX hydrocarbons dissolved in water. They provide quantitative results in ppm of the compound used to calibrate the system. When measuring blind samples of p-xylene the probes correlate with the GC at the 99% level. The blind samples run with benzene (RRF of 6.233) showed a quantitative correlationof 97% with the GC and UV. Toluene (RRF of 2.857) gave similar results with a correlation of 98%. Ethyl benzene (RRF of 1.034) had a correlation of 98%. And when run with a 1:1:1:1 mixture of BTEX the average RRF is 1.730 and the correlation was 98%.



And Quick In the presence of product, the sensors achieve a 95% detection level in approximately 5 minutes. When the sensors are removed from contaminated water containing a product and placed in chemical-free water, the fall back time to a baseline reading occurs in approximately 2 minutes.


Ken Wilcox Associates, Inc.