INDUSTRIAL HYGIENE

1. INDUSTRIAL HYGIENE Respiratory System

2. ENTRY INTO BODY • The approximate order of descending effectiveness for • Intravenous administration • Inhalation route • Intraperitoneal • Subcutaneous • Intramuscular • Intradermal • Oral • Topical

3. ENTRY INTO BODY • Industrial exposure to toxic agents is most frequently a result of • Inhalation • Topical

4. Macrostructure • Surface area – 100 m2, 1 m2 per kilogram of body weight • Lung • Lung structure • Chest cavity • Diaphragm

5. Respiratory System

6. RESPIRATORY SYSTEM • Anatomy • Nose • Contains Two Methods of Trapping Particles • Mucus • Cilia • Pharynx • Throat Contains the Epiglottis • Larynx • Voice Box (Vocal Cords) • Serves As a Passageway for Air Between the Pharynx and the Trachea -

7. RESPIRATORY SYSTEM • Anatomy • Trachea Windpipe Divides Into Two Bronchi • Bronchi Enter Lungs • Bronchi Divide Into Smaller Tubes (Bronchioles) • Tree Like Structure of 25 -100 Million Branches -

8. RESPIRATORY SYSTEM • Pulmonary Characteristics • Gas Exchange • Metabolic Organ • Immunologically competent • Secretory organ • Barrier to inhaled toxins • Excretion organ

9. Lungs • Target organ • Exposure by Inhalation • Systemic Exposure • Portal of Entry

10. Physiology • Gas exchange • Perfusion • Flow of blood to the lungs • 70-80 cm3 per heartbeat • Diffusion • Moving gases over blood barriers • Limiting point, minimize , perfusion limited • Ventilation • Flow of air into the lungs

11. Physiology • Gas exchange • TLC • Total lung capacity • 5700 cm3 • RV • Residual volume • 1200 cm3 • VC • Vital capacity • 4500 cm3 • TV • Tidal volume • 500 cm3 • Moved with each breath while resting

12. Factors that Influence Toxicity of Inhaled Substances • Physical properties • Physical state • Size and density of particles, mist, aerosol • Shape and penetrability • Solubility • Hygroscopicity • Electric charge

13. Microstructure • The size particle which has the greatest retention in the lung is 1 to 5 microns • For particles to gain access to the alveolar regions of the lung, the particles must have aerodynamic particle sizes less than 5.0 microns • Particles in the size range of 1 to 5 microns penetrate the lungs into the alveolar area where they have less chance of being cleared from the lung • Particles less than 1 micron tend to stay in the airstream and are breathed back out, while particles greater than 5 microns are captured in the upper respiratory tract and do not get to the lower portions of the lungs

14. Factors that Influence Toxicity of Inhaled Substances • Chemical properties • Acidity and alkalinity • Propensity to combine with substances in lung and tissues • Fibrogenicity • Antigenicity

15. Respiratory Protection Program • Requirements • Medical questionnaire • Training • Fit testing • Respirator selection • Inspection • Cleaning • Storage

16. Steps In Choosing Respiratory Equipment • Identification of hazard • Evaluation of hazard • Selection of proper respiratory • equipment by a qualified • professional

17. Respiratory Equipment • Negative Pressure • Positive Pressure • Tight Fitting Facepiece • Loose Fitting Facepiece + + _ + _ + _ + _ + _ _ _

18. Tight Fitting Facepieces • If the respirator has a tight fitting facepiece, • the wearer must be clean shaven

19. Protection Factors Maximum Protection Permissible Exposure = Factor X Exposure Concentration {PF} Limit {PEL} Protection Factor Respirator Type • Dust Mask • Quarter Face APR • Half Face APR • Full Face APR • PAPR • SCBA/Pressure Demand 1 2.5 5 25 50 5,000

20. Types Of Respiratory Equipment • Air Purifying {APR} • Air Supplying

21. Air Purifying Respirators • Requirements For Use • Contaminant Must Be Known • Concentration Of Contaminant Must Be Known • Contaminant Must Have Adequate Warning Properties WARNING Respiratory Protection Needed!!

22. Air Purifying Respirators • Limitations • Protection Only For Hazards Listed On Cartridge • Do Not Protect Against Temperature Extremes • Do Not Protect Against Oxygen Deficiency

23. CARTRIDGE COLORS Color Assigned: Contaminant: White White With Green Stripe White With Yellow Stripe Black Green Green With White Stripe Acid Gases Hydrocyanic Acid Gas Chlorine Gas Organic Vapors Ammonia Gas Acid Gases + Ammonia Gases

24. CARTRIDGE COLORS Color Assigned: Contaminant: Yellow Yellow With Blue Stripe Brown Purple {Magenta} Canister Color For The Containment With Gray Stripe Red With Gray Stripe Acid Gases +Organic Vapors Hydrocyanic + Chloropirin Acid/Ammonia Gas + Organic Radioactive Materials {HEPA} Particulates {Dusts, Fumes, Mists, Fog Or Smoke} All Of The Above Listed Atmospheric Contaminants

25. Air Purifying Respirators • Types • Disposable • Quarter Face • Half Face • Full Face • Powered Air Purifying {PAPR}

26. Disposable Respirators • Simple Filtering Devices • Snug Fit Is Required

27. Powered Air Purifying Respirators • Same Limitations As Other Air Purifying Respirators • Provide A Higher Protection Factor Due To Positive Pressure In The Facepiece

28. Supplied Air Respirators • Types • Airline • Self Contained Breathing Apparatus {SCBA }

29. Supplied Air Respirators • Cannot provide protection against every type of hazard • Inspect before every use • Clean after every use • Store properly

30. Fit Test • Types • Qualitative • Quantitative

31. Legionnaires Disease • Caused by • Poorly maintained cooling towers • Bacteria • Inhalation of an aerosol • Humidifiers

32. Pneumoconiosis • Group of diseases of the lung that are caused by inhalation of dusts • Asbestos • Cotton dust • Coal dust • Crystalline silica