Horizon Engineering uses a fleet of four stand-up vans for almost all emission testing work. Air-conditioned, finished, clean space is allocated for sample recovery, analyzers, "manual" trains, gear that goes up on stacks, support equipment, and personnel. Three of the trucks are heavy duty diesels with air suspension for protecting sensitive equipment. Power can be supplied by either 120V or 480V, three phase. The trucks' layouts are designed to keep noisy pumps and bulky equipment in compartments outside.

Each is equipped with a set of basic analyzers (CO2, O2, CO, and NOx) with space for other analyzers (VOC, SO2, or duals of the same type) needed for specific work. Data is logged with a PC based data acquisition system utilizing custom software designed for emission testing. All trucks also utilize strip-chart recorders for backup along with uninterruptible power supplies for the data systems.

A dedicated trailer is used for jobs that require on-site GC analysis. The GC is an H-P 5890 Plus with Chemstation Software setup exclusively for air sampling and analysis. FID and FPD detectors and an assortment of columns are utilized to analyze many organic and sulfur gases. The all-heated system can take samples from bags or use a direct interface. Sampling can be automated for around-the-clock sampling and analysis.
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