Wirelessly Integrated Installed
Direct Reading Instruments (DRIs)
A series of wirelessly integrated direct reading instruments (DRIs) are being tested for use at the Hanford Site. DRIs either use the concept of photoionization to detect a broad spectrum of vapors or use electrochemical techniques to detect a specific chemical(1). The photoionization detector (PID) consists of a short-wavelength ultraviolet (UV) lamp shining onto a small cell containing the gas sample. Within the cell is a set of electrodes that have an electrical potential applied. The UV light photoionizes trace organic compounds, but not the air, resulting in electrons being ejected and forming positively charged molecules. The electrons and positive ions are propelled to the electrodes and the resulting current is proportional to the gas or vapor concentration.
These monitors will be placed at various work locations to track any potential exposure to chemicals and locations to immediately respond to hazards. These monitors (shown below) will be wirelessly integrated to ensure continuous communication.
Meshguard Ammonia Sensor
The MeshGuard provides real-time measurements of ammonia (NH3) and optional alarm signals when exposure exceeds preset limits. The MeshGuard provides ammonia monitoring with wireless real-time data availability via wireless communications to the tank farm plant software (Tank Farm Machine Control System ‘TFMCS’and OSI/PI Historian) and plume dispersion software (SAFER Systems).
Gastronics Fixed Instrument Skid
The Gastronics Fixed Instrument Skid (FIS) provides real-time gas measurement for ammonia (NH3), total volatile organic compounds (VOC), nitrous oxide (N2O) and directional wind data. The system is specifically designed for long-term outside use and includes optional alarm signals, solar/battery power and wireless data transmission. The wind information measured by the units will be used to understand dispersion of chemical vapors and improve the accuracy of dispersion models. This data, along with other DRI instrument data, will be transmitted to the VMD data collection/management system, i.e. TFMCS and SAFER Systems.
The HAZSCANNER™ environmental perimeter air station (EPAS) wireless is an ambient air quality monitor capable of measuring and documenting gasses and vapors with up to 11 electrochemical sensors, PIDs, and meteorological data. The Hanford-specific HAZSCANNER™ monitor contains eight sensors that monitor VOCs, sulfur dioxide (SO2), methane (CH4), carbon dioxide (CO2), nitrogen dioxide (NO2), hydrogen sulfide (H2S), carbon monoxide (CO), ammonia (NH3) and contains a suite of meteorological instruments. The EPAS provides direct readings in real time availability to TFMCS and SAFER Systems.
Fixed Forward Looking Infrared Camera (FLIR)
The Fixed Forward Looking Infrared (FLIR) camera is an optical gas imaging (OGI) instrument that visualizes and pinpoints gas or vapor emissions from a distance. The system detects infrared energy (heat) and converts it into an electronic signal which is then processed to produce a thermal image on the unit’s onboard video monitor. The OGI camera provides remote indication that chemical gases/vapors (visible or invisible) are present based on the difference in temperature of the gas from the background temperature.
Area/Stack Automatic Sampler and Cases
The Area/Stack Autosampler is designed to remotely capture samples with whole air samples and on sorbent media for analysis utilizing GC-MS. Seven autosampler units will be located around AP and A Farms, including one sampling directly from the AP exhauster and one from the A-103 passive breather filter.
(1) The PID Handbook Theory and Applications of Direct-Reading Photoionization Detectors, RAE Systems