Industrial Hygiene Control of Airborne Chemical Hazards

AN INTRODUCTION TO INDUSTRIAL HYGIENE CHEMICAL HAZARD CONTROL An Overview of Industrial Hygiene The Spatial Spectrum of Exposure Scenarios The IH Paradigm of Control Priorities The Approach, Organization, and Philosophy of this Book BASIC GAS AND VAPOR BEHAVIOR Gas and Vapor Definitions Vapor Pressure Changes with Liquid Temperature IH Uses of Dalton's Law IH Uses of the Ideal Gas Law The Effects of T and P on Airborne Concentration The Effects of T and MW on Plume Density Dense Vapors BASIC AEROSOL BEHAVIOR How Aerosols Differ from Gases and Vapors Aerosol Definitions Particle Diameter Distributions Modeling Particle Behavior Stokes and Aerodynamic Diameters Aerosol Diameters and Human Health CHEMICAL EXPOSURE CONTROL CRITERIA Performance and Specification Standards Health Criteria for Chemical Control Safety Criteria for Chemical Control The Oxygen Deficiency Criterion Comparisons among Criteria OSHA Ventilation Standards Open-Surface Tanks Appendix VAPOR GENERATION AND BEHAVIOR Mechanisms of Vapor Generation Mechanisms of Plume Dispersion Four Universal Airborne Chemical Exposure Scenarios Four Settings with Vapor Accumulation Vapors from Incomplete Evaporation with No Ventilation Vapors from Complete Evaporation with No Ventilation Differentiating between Complete from Incomplete Evaporation Vapors from Continuous Evaporation with Ventilation VAPOR PRESSURE IN MIXTURES Mixtures Defining Liquid Mixtures Raoult's Law for Ideal Liquid Mixtures The Need for an Empirical Adjustment to Raoult's Law Methods to Predict an Empirical Adjustment to Raoult's Law Examples of Mixtures Henry's Law Measuring Mixtures Experimentally Applying Predictive Methods to Mixtures CHANGING THE WORKPLACE The Technologic Dimension of Change The Psychologic Dimension of Change The Economic Dimension of Change Implementing the IH Control Paradigm SOURCE CONTROL VIA SUBSTITUTION Alternative Technologies Volatility and Alternative Chemicals Aqueous Solvents Semiaqueous Solvents Organic Solvents Toxicity versus Volatility The Vapor Hazard Ratio Using VHR and Other Indices in Risk Management OTHER SOURCE AND NONVENTILATION PATHWAY CONTROLS Concepts Some Nonvolatile Chemical Source Controls Some Volatile Chemical Source Controls Effects of Modifying Volatile Chemical Source Variables Work Practices as an Exposure Control Automation as an Exposure Control Separation as an Exposure Control Isolation as an Exposure Control Fundamental Nonventilation Control Equations AN OVERVIEW OF LOCAL EXHAUST VENTILATION Local Exhaust Ventilation Definitions Principles of Local Exhaust Ventilation The LEV Design Sequence VENTILATION FLOW RATES AND PRESSURES Applying Conservation of Mass to Ventilation Applying Conservation of Energy to Ventilation Static Pressures (P and SP) Velocity Pressure Total Pressure and Pressure Losses Compilation of the Fundamental Ventilation Control Equations Appendix MEASURING VENTILATION FLOW RATES Qualitative Air Flow Indicators Air Velocity and Manometers Aerodynamic Velocity Meters Thermodynamic Velocity Meters The Boundary Layer Assessing Flow in Ducts Calibrating Anemometers DESIGNING AND SELECTING LOCAL EXHAUST HOODS Local Exhaust Hood Design Principles Selecting a Control Velocity Using the DallaValle Equation Designing a Slotted Collection Hood Designing a Hood Using an ACGIH "VS" Diagram Designing a Hood for an Open Surface Tank Designing a Canopy Hood over an Isothermal Source Designing a Canopy Hood over a Hot Source Designing a Push-Pull Hood System Using an Air Shower Using Commercial and Other Specialty Hoods PREDICTING PRESSURE LOSSES IN VENTILATION SYSTEMS A Primer on Energy and Pressure Losses Energy Losses from Hood or Duct Entry Selecting a Duct Velocity Selecting the Duct Size and Material Energy Losses from Friction in Straight Ducts An Example of Hood Entry and Duct Friction Losses Turbulence in Duct Fittings Losses from Elbows Losses from Duct Contractions Losses from Duct Expansions Comparing Contraction and Expansion Losses Energy Losses in Branched Duct Systems The LEV Design Worksheet EXHAUST AIR CLEANERS AND STACKS Air Cleaning Needs and Options Air Cleaner Selection Criteria Particulate Aerosol Collectors Aerosol and Gas Collectors Gas and Vapor Collectors Exhaust Stacks and Reentrainment VENTILATION FANS Fans have Two Pressures Fan Performance Matching Fan Performance to System Requirements Some Air Mover Terminology Axial Fans Centrifugal Fans The Fan Laws Fan Selection and Installation VENTILATION OPERATING COSTS Fan Efficiency and Power Consumption Electricity Costs for Fans Make-Up Air Heating Costs for Make-Up Air Cooling Costs for Make-Up Air Energy Conservation LEV SYSTEM MANAGEMENT Why Monitor System Performance When to Monitor System Performance Where, What, and How to Monitor System Performance LEV Troubleshooting Postinstallation LEV Adjustments Appendix GENERAL VENTILATION AND TRANSIENT CONDITIONS General Ventilation and Chemical Control Components of the Dilution Ventilation Model The General Solution to the Dilution Ventilation Model Concentrations during a Transient Increase Concentrations during a Transient Decrease Accumulation with No Ventilation GENERAL VENTILATION IN STEADY STATE CONDITIONS The Concentration in Steady State Conditions Normal Building Ventilation Requirements Methods to Estimate a Contaminant Generation Rate General Ventilation (HVAC) Systems Controlling Exposures Via Dilution Ventilation Sources of HVAC and Indoor Air Quality Problems ADMINISTRATIVE CONTROLS AND CHEMICAL PERSONAL PROTECTIVE EQUIPMENT Administrative Controls Personal Protective Equipment Basic PPE Program Management Terms and Concepts Regarding Chemical PPE Recognizing Dermal Hazards Chemical Protective Gloves Chemical Protective Clothing Levels of PPE Ensembles Appendix RESPIRATOR CONTROLS Respirator Terms and Concepts Different Kinds of Protection Factors Variables Affecting Protection Factors Respirator Fit and Seal Testing Respiratory Protection Program Requirements A Respirator Selection Protocol Appendices APPENDICES Index