study guide need by tomorrow afternoon

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 4 Types of Health Hazards

 Physical

 Noise, vibration, extreme temperature, extreme

pressure, illumination, radiation

 Chemical

 Gases, vapors, particulates, liquids

 Biological

 Bacteria, viruses, fungi, parasites, organic aerosols,

plants, animals

 Ergonomic

 Repetitive motion, forceful motion

 Awkward posture, static posture

 Vibration and cold

EHST 3700/3701:

Industrial Hygiene

 To recognize the basic structure and functions of the human respiratory tract

 To list the major classifications of airborne hazards

 To identify airborne hazards and their source processes

 To describe occupational diseases associated with exposure to airborne contaminants

 To understand how spirometry is used to evaluate lung function and detect patterns of lung damage

 To recognize situations where oxygen-deficient atmospheres might exist

 To explain the difference between simple and chemical asphyxiants

 To explain the mechanisms leading to hypoxia

 Anatomy and function of the respiratory

system

 Airborne hazardous materials

 Occupational diseases associated with

airborne particulates

 Oxygen-deficient atmospheres

N a so

p h a ry

n g e a l

re g io

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T ra

c h e o b ro

n c h ia

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re g io

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D is

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Cilia lining the mucous membrane

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Bifurcation of Airways The Alveoli

pneumocytes

 Removal of large particles (10 um) in the

nose and upper airways

 Bifurcation of respiratory tract

 Cough reflex

 Macrophages

 Mucociliary elevator

The Mucociliary Elevator

Sizes of Various

Airborne Particles

Micron (micrometer) –

one one-thousandth of a

millimeter (0.001 mm)

1 millimeter = 1/10 cm

 Used to compare particles with irregular shapes (i.e. dusts and fibers) to those with regular shapes (i.e. droplets and mists)

 Equal to the diameter of a reference spherical material with a unit density of one that has the same settling velocity as the contaminant particle

 To compare masses that have very different sizes, shapes and density

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 Gases and vapors

 Particulates or aerosols

 Dusts

 Mists

 Fumes

 Oxygen-deficient atmospheres

 Gas

 In gaseous state

at standard

temperature

(25C) and

pressure (760

mmHg)

 Vapor

 In solid or liquid

state at standard

temperature

(25C) and

pressure (760

mmHg)

Toxicant Pulmonary Damage

Ammonia, NH3 Irritation

Coke oven emissions Lung cancer

Hydrogen fluoride, HF Irritation, edema

Nickel carbonyl, NiCO Nasal and lung

cancer; acute edema

Nitrogen oxides: NO, NO2, HNO3 Emphysema

Ozone, O3 Emphysema

Phosgene, COCl2 Edema

Perchloroethylene, C2Cl4 Edema

Sulfur dioxide, SO2 Irritation

Toluene 2,4-diisocyanate Sensitizer, edema

Xylene Edema

Composed of usually dry particles

Produced by some physical processes

(i.e. crushing, polishing, grinding)

Adverse health effects

 Irritation

 Allergic responses

 Systemic diseases

 Cancer

 Airborne droplets

 Generated by any operation involving

liquids

 Created when air or another gas is

introduced into a liquid, causing the

liquid to aerosolize

 Health effect

 Irritation

 Inflammation

 Pulmonary edema

 Allergic responses

 Produced when materials (i.e. metal) are

heated to the point where they become a

gas or vapor

 Condenses to form small particles

 Diameters from 0.1 to 100 um

 Sources: welding, torch cutting, buffing

or grinding

Fumes are NOT

gases or vapors.

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http://www.deseretnews.com/article/635160379/Floor-solvent-fumes-send-10-employees-to-hospital.html http://www.nhs.uk/chq/Pages/2531.aspx?CategoryID=54&SubCategoryID=131

 Sampling for a particular size range of

particles

Size

Fraction

Particle

Aerodynamic

Diameter, um

Site/ Region of

Deposition

Inhalable >10 Nasopharyngeal

region

Thoracic 5 – 10 Thoracic region

Respirable 0.5 - 4 Alveolar region

 Pneumoconiosis

 “Dust in the lungs”

 Reaction of the lung tissue to the presence

of dust

 Examples:

 Silicosis

 Asbestosis

 Byssinosis

 Coal worker’s

 Scarring of the lungs due to breathing of dust

containing crystalline silica

 Characterized by the development of nodules

that form in response to the dust

 Complications: hypertension, cor pulmonale

 Crystallized silicon dioxide (SiO2)

 Most commonly occurs as sand

 Widely distributed in hard rocks and minerals

 Tridymite and cristobalite are more potent

than quartz in causing silicosis.

Tridymite Cristobalite Quartz

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 Non-crystalline silica

 Diatomaceous silica

 Diatomaceous earth

Form 2010 ACGIH

TLV

Equation to Calculate

OSHA PEL

Amorphous (non-

crystalline) silica

--- 80 mg/m3

% SiO2 + 2

Crystalline silica –

quartz (respirable)

0.025 mg/m3 10 mg/m3

% SiO2 + 2

Crystalline silica –

quartz (total)

--- 30 mg/m3

% SiO2 + 2

Crystalline silica –

cristobalite (resp)

0.025 mg/m3 ½ (10 mg/m3)

% SiO2 + 2

Crystalline silica –

tridymite (resp)

--- ½ (10 mg/m3)

% SiO2 + 2

SCENARIO 1

 % Quartz in sample = 5.1

 PEL = 10 mg/m3 = ?

% SiO2 + 2

SCENARIO 2

 % Quartz in sample = 8.3

 PEL = 10 mg/m3 = ?

% SiO2 + 2

 PEL = 10 mg/m3 _

% Quartz + 2 (%Crystobalite)

+ 2 (%Tridymite) + 2

 Percentage in sample

 % quartz = 5.2

 % crystobalite = 2.3

 % tridymite = 0.9

 PEL = ?

 Characterized by lesions forming around

inhaled coal particles  Asbestos fibers

 Glass fibers

 Ceramic fibers

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 A chronic condition marked by scarring of the

lungs that is caused by prior occupational

exposure to asbestos

 Group of naturally

occurring minerals that

are resistant to heat and

corrosion

 Commonly used in

construction before 1975

 Have been used in

insulation for pipes, floor

tiles, building materials,

and in vehicle brakes and

clutches

Amphibole Serpentine

 Bronchogenic

carcinoma

 Mesothelioma

 Rare form of cancer

that develops from

the protective lining

that covers many of

the body's internal

organs

(mesothelium)

 Occupational exposure:

 Asbestos mining and milling

 Construction

 Ship repair

 Fireproofing

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 The respiratory tract is a significant and

efficient route for airborne hazards to enter

the body.

 The respiratory tract has protective

mechanisms against airborne hazards.

 Examples of airborne hazards are gases,

vapors and particulates (dust, mist and

fumes).

 Size-selective sampling is used to measure

the amount of specific sizes of airborne

particulates, considering that particle size is

associated with the site of deposition.