Laserfiche WebLink
1 <br /> FIELD MONITORING EQUIPMENT <br /> 1.0 INTRODUCTION <br /> ' Many hazards may be present when working at hazardous wastes sates or responding to <br /> hazardous materials Four conditions can occur oxygen deficient atmospheres, flammable and <br /> ' explosive atmospheres, toxic atmospheres, and radioactive environments Toxic atmospheres includes <br /> harmful gases, vapors, mists, and dusts <br /> 1 <br /> When first approaching a hazardous waste or spill site the potential hazards must be <br /> ' recognized and exposure risks evaluated This can be in the form of a methodical preliminary site <br /> survey Information gained will most likely be limited but will provide enough data to make some <br /> ' initial decisions These might include respirator and protective clothing selection or further definition <br /> of the hazard by qualitative assessment <br /> Once the plan of action, based on the initial survey, is done hazard evaluation is not over <br /> No matter how passive the situation appears, the site is potentially very dynamic Removing <br /> underground storage tanks and drums or excavation may introduce new hazards To ensure a safe <br /> ' working environment, continuous or periodic monitoring of the hazards must be performed <br /> ' To perform initial site surveys and subsequent periodic monitoring, various portable direct- <br /> reading instruments must be available Such instruments range from portable gas chromatographs to <br /> passive dosimeters The variety of instruments and operating principles is wide New instruments <br /> ' are introduced each year incorporating advancements in technology <br /> ' With such a variety of portable instrumentation available, it follows that each serves a specific <br /> purpose Some display an immediate readout upon each manual sample taken Others monitor <br /> ' continuously and have built-in alarms to signal a potential hazard Many instruments are designed to <br /> sample over a time period to determine a time-weighted average exposure These may be active or <br /> passive in design There are instruments that use unique components to determine the concentration <br /> of a hazardous substance <br /> O - 1 <br />