Optical Remote Sensing Devices - Some Manufacturers and Consulting Firms - facegis.com
Optical Remote Sensing Devices - Some Manufacturers and Consulting Firms

On this page you will find adresses and links to the companies who manufacture open-path monitoring equipment and to environmental consulting firms who have experience in operating this equipment.

We have attempted to include all the companies in this field, not just those which have been involoved in the Tosco/Unocal project. If you know of a manufacturer or enironmental firm who should be on this list, please contact us.

Optical Remote Sensing Devices - facegis.comPerspectUV

SCI-TEC Instruments Inc.

1526 Fletcher Rd. Saskatoon, SK

Canada S7M 5M1 (306) 934-0101


Sci-Tec was awarded the contract to provide the UV monitors for the Tosco SFAR fenceline system. Theirs is a bi-static system, consisting of separate transmitter and reciever units. This UV system employs a unique design featuring a dedicated solid-state interferometer for each compound monitored. With complete systems starting around $50K, these units are considerably less expensive than some of their competition.

Optical Remote Sensing Devices - facegis.comAIR SENTRY FTIR

Environmental Technologies Group

1400 Taylor Avenue P.O. Box 9840

Baltimore, MD. 21284-9840

(800) 635-4598


ETG was awarded the contract to provide Infrared (FTIR) monitors for the Tosco system. These are the most widely used open-path monitors in the United States. U.S. EPA has made extensive use of these devices, mostly monitoring downwind of Superfund cleanup sites. Like many of these manufacturers, ETG is primarily a defense contractor. These FTIR units have been used at different times by various branches of the U.S. military, although the details of much of this work remain classified.

Communities for a Better Environment in San Franciso has been able to procure one of ETG's older FTIR units, and has undertaken monitoring projects in a number of industrial communties in and around the Bay Area. It was through this "hands-on" use of this instrument, and training provided by ETG, that CBE and SEA members were able to gain the expertise necessary to perform our own analysis of the raw FTIR spectral data provided to us by the refinery. 


Optical Remote Sensing Devices - facegis.comGasfinder TDLAS

Boreal Laser Inc. (403) 987-4382

#13, 51127 R.R. 255

Spruce Grove, Alberta, Canada T74 1A8


Boreal was awarded the contract to provide Tunable Laser monitors for the Tosco system. Each indidual monitor is designed to monitor for one specific gas. At Tosco SFAR, these units are used to monitor hydrogen sulfide and ammonia.

These lightweight and portable units are uni-static in design, and utilize the same type of "retroreflector" as pictured above with the ETG FTIR system. At the Tosco site, these TDLAS monitors share retroreflectors with the FTIR units.

The maximum one-way pathlength for these units is rated at an impressive 2 kilometers. When these units were installed at Tosco, they had to be intentionally (mis)aligned off-center of the retroreflectors,( to avoid over-saturation caused by too much return signal) even at 920 meters! 


Optical Remote Sensing Devices - facegis.comRemote Molecular Monitor

AIL Systems Inc.

Commack Road

Deer Park, NY 11729 (800) 264-7477

AIL Web Site


AIL's "Remote Molecular Monitor" is another FTIR-type open-path monitor. This unit is direct competition for the ETG "Air Sentry". At the time we were ready to start our 6-month test program AIL's device was still in the prototype stage, and was not considered for that reason. Apparently, this unit is now ready for market, and AIL has at least one deployed in the field that we know of.

If you visit AIL's website, you will see that AIL is primarily a defense contractor. 


Optical Remote Sensing Devices - facegis.comOpsis

Current U.S. distributor unknown. Web link below is for their distributor in the U.K.



The Swedish-made Opsis system has been around for several years, and these units are used in several Western European cities to measure smog levels. Despite their sucess in Europe, this company has not had any success marketing their product in the U.S., and to our knowledge, still do not have a single commercial installation here.

The opsis device has acheived "equivalency status" with EPA standard reference (canister) methods for three compounds: NO2, SO2 and Ozone. To date, no other manufacturer of open-path monitoring equipment has applied to EPA for equivalency status. EPA does have one of the opsis units which they have been using for researching smog levels in urban areas in the South and East. 


Optical Remote Sensing Devices - facegis.comSANOA

Groupe Environnement S.A.

111 Bd Robespierre,

78300 POISSY, France Tel 33-1-39 22 38 00


We don't know that much about this French-made Ultraviolet monitor, although we have heard some positive feedback from consultants who have worked with them in the field. This unit was not considered for the Tosco installation, mostly because its advertised specifications indicated that it could not meet the requirement to cover a one-kilometer path with one instrument. We did see this unit at an AWMA trade show in 1995. Definetly the coolest looking of any of the monitors. 


Optical Remote Sensing Devices - facegis.comRadian International

Radian International LLC, an international environmental, engineering, and technical services firm based in Austin, Texas is a joint venture of Radian Corporation and Dow Environmental Inc.


Radian is not a typical equipment manufacturer, in the sense that they don't have a piece of hardware to sell. Instead, they build site-specific instruments to meet a clients needs . . . and then see the project all the way through, handling all of the data analysis and other related consulting services.

The web link above will take you to a page where they briefly outline an open-path FTIR system which they installed, and are operating, for a client in Texas.

Robert Spellicy Ph.D. with Radian is recognized as one of the foremost experts on open-path monitoring in the United States. He is widely published in this field, and has worked extensively with U.S. EPA in developing standards for open-path monitoring systems 

Optical Remote Sensing Devices - facegis.comInfrared Analysis Inc.

1334 North Knollwood Circle

Anaheim, CA 92801 (714) 236-8900


Infrared Analysis Inc. has long been a leading supplier of products and services relating to Infrared Gas Analysis. Their "library" of infrared reference spectra has become the industry standard, and is utilized by all the manufacuters of FTIR open-path instruments listed on this page. SEA uses this library in our own analysis of the infrared spectra from the Tosco site.

Infrared Analysis Inc. also just introduced a new product which is designed to allow open-path measurement when coupled with a standard laboratory spectrometer. This new (multi-pass) device is probablly not well suited for fenceline monitoring applications, but does mark another step forward in the field of open-path FTIR spectroscopy.

Optical Remote Sensing Devices - facegis.com

The Air & Waste Management Association

One Gateway Center, Third Floor

Pittsburgh, PA 15222 - (412) 232-3444 http://www.awma.org/

If you really decide to get into this stuff, sooner or later you'll find yourself at one of the conferences hosted by the AWMA. The attendees at these conferences tend to include an interesting mix of equipment manufacturers, environmental consultants, regulators, and heavy industry representatives.

These conferences, held at venues all over the U.S., are where most of the key technical papers on optical remote sensing are presented. The AWMA has a number of very good publications regarding optical remote sensing which are available to the public. 


Optical Remote Sensing Devices - facegis.comRemote Sensing Air, Inc.

8147 Delmar Blvd., Suite 219

St. Louis, MO. 63130

(314) 863-9801

RSA is one of the few environmental firms in the country who specialize in the field of optical remote sensing. RSA was the contractor during the "interim" phase of the fenceline montioring project, while the refinery was still owned and operated by Unocal.  

Optical Remote Sensing Devices - facegis.comTerra Air Services

2950 N. Loop W., #1050

Houston, TX 77092

(713) 956-2185 - http://www.Terra-air.com/

Terra is the firm that eventually won the contract to develop and administer the permanent fenceline monitoring system at the refinery. The monthly reports which we recieve on the system are prepared by Terra. The raw spectral data and database files which we also recieve come directly form Terra. 

Optical Remote Sensing Devices - facegis.comCarala Air Associates, Inc.

2551 Rt. 130

Cranbury, NJ 08512-9575 (609) 395-1110

Carala is another extremely capable environmental firm with a great deal of experience in optical remote sensing. The Carala group were involved with the original 6-month test phase of the (Unocal) fenceline monitoring system as subcontractors.

Sorce: http://www.fenceline.net