(EHS340) Exam 4

Thermal Stress

What is evaporative cooling?

It is the primary ______ of the body.

What is it affected by?

Evaportaion of sweat to maintain temperature balance 

Cooling mechanism 

Humidity

What is Heat Stress?

Employee exposure to discomfort and dangers caused extreme temperatures.

What are 4 of the 6 common heat disorders workers might be at risk of experiencing?

(1) Heat Stroke

(2) Heat Exhaustion

(3) Heat Cramps

(4) Heat Rash

(5) Heat Fatigue

(6) Heat Collapse (fainting)

What is heat stroke?

What are the 5 symptoms of heat stroke?

When body’s temperature regulation fails, leading to critical increase in body temperature.

(1) Confusion

(2) hot dry skin

(3) irrational behavior

(4) high body temperature (104.5°F+)

(5) loss of sweating

Heat stroke require ______ medical attention.

What are the 3 treatments for heat stroke?

Immediate

(1) cooling with wet skin

(2) air circulation

(3) fluid replacement

What causes heat cramps?

What is are the 3 main symptoms?

What are 2 ways we can prevent heat induced cramping?

Salt and potassium depletion during intense physical labor

Muscle spasms in arms, legs, and abdomen

(1) Gradual acclimatization

(2) Use of electrolyte drinks to replace lost minerals

What is acclimatization?

What are 3 benefits?

Body’s physiological adaptation to heat exposure

(1) Lower cardiovascular strain

(2) efficient sweating

(3) stable body temperature

What is hypothermia?

What happens to core body temperate during hypothermia?

Severe cases of hypothermia are ________.

When body can't produce enough heat to counter environmental heat loss

It drops below normal

Life threatening.

If body heat loss exceeds heat production, hypothermia can occur at temperatures as high as _____?

What are the 4 symptoms of hypothermia?

What’s the body’s defense mechanism?

65°F

(1) Shivering

(2) Confusion

(2) Slurred speech

(4) Drowsiness

Works to maintain core temperature

How does wind chill impact heat loss?

Wind chill increasing risk of _____.

Wind increases the rate of heat loss from exposed skin

Cold stress

What does WBGT stand for?

WGBT is a metric used to access ______.

This assessment is used for the _____ of employees in _____ work conditions.

Wet Bulb Globe Temperature

Environmental heat load

Safety ; hot

What is the 2 goals of WBGT measurements?

(1) Estimate worker metabolic heat load

(2) develop safe work/rest regimens

What are the three temperature sensors used in WGBT measurements?

(1) Dry bulb

(2) wet bulb

(3) globe thermometers

What 3 things do WBGT measure?

(1) Air temperature

(2) Humidity 

(3) Radiant Heat

What organization published TLVs for heat stress?

ACGIH

What are 4 examples of engineering controls to reduce heat stres?

Ventilation

Air Cooling and Conditioning

Local Cooling

Fans

Acclimatization of workers lowers the risk of what two

Heat cramps

Heat fatigue

Heat collapse 

What are the 4 stress factors for cold stress?

Cold temperature

wind

dampness

cold water 

Radiant heat is heat transmitted as _________ without _____ of matter.

Electromagnetic energy

Movement

Conduction is heat transfer via ______

Convection is heat transfer via ______

2 bodies in direct contact

A moving medium such as gas or liquid

Ventilation 

What creates natural ventilation systems?

Pressure differences are caused by _____ and result in _____.

Natural pressure differences causing air to rise and escape

Heat ; Convection currents

What does Industrial Ventilation use? Give an example.

They move air _____ than natural ventilation.

Why is industrial ventilation used?

Mechanical systems ; fans

Faster

Removes contaminants before they reach hazardous level

What is Static Pressure?

Where is it exerted?

Is it positive or negative?

The pressure developed in a duct by a fan

Exerted in all directions

Can be negative or positive

What is Velocity Pressure?

Where is exerted?

Is it positive or negative?

Created as moving air

Exerted only in direction of airflow

Always positive

What causes poor indoor air quality?

What is a plenum?

What is replacement air?

Poor ventilation

Low-velocity chamber for pressure distribution

Air supplied to replace exhausted air

What is Capture Velocity?

What is Coefficient of Entry?

Hood-induced velocity to capture contaminants

A way to measure hood efficiency

Industrial ventilation aims to recreate ________ by managing _______ .

Air moves from ______ to ______ areas, influenced by ______ conditions.

Controlled natural ventilation ; air movement 

high-pressure ; low-pressure ; thermal 

What is dilution ventilation?

What is Local Exhaust Ventilation?

General exhaust to dilute contaminants.

Captures contaminants at the source.

What is Laminar Flow?

What is Turbulent Flow?

Smooth, parallel air flow

Mixing velocities in multiple directions.

Radiation

What are the 4 Ionizing particles? Give an example of each.

(1) Alpha ; Uranium in ceramic glaze coloring

(2) Beta ; Research tracers

(3) Gamma ; Sterilizing medical products 

(4) X-rays ; Radiography 

What is ionization?

What is ionizing Radiation? 

What are the 2 types?

Atoms become ions by gaining or losing electrons

Production of ions by interacting with matter

Direct and indirect

Non-Ionizing Radiation is less ______ and is apart of _____ exposure.

Understood ; everyday 

What is radiological half life?
What is biological half life?

What is effective half life?

Time it takes for half of the atoms in a radioactive sample to decay into a different form

Time required human body to eliminate a substance via metabolism

Time for a radioactive substance to lose half its activity, combining radiological and biological half-lives

What does ALARA stand for?

The inverse square law states that Dose rate _____ rapidly as distance ______.

As Low as Reasonably Achievable

Descreases ; increases 

What can block alpha particles?

What can block beta particles?

What can block gamma rays?

Sheet of paper

Sheet of aluminum

Lead

What is the NRC?

What do they govern?

What is an RSO?

What do they oversee?

Nuclear Regulatory Commission

Radiation protection standards and requirements.

Radiation Safety Officer (RSO)

Compliance and safety practices.

Alpha particles are ______ ionoizing, with _____ penetration.

Gamma rays are ________ ionizing, with ______ penetration

Strongly ; low

weakly ; high

Biological Hazards

What is a zoonotic disease?

What’s an example of zoonotic disease?

An infectious disease of humans caused by a pathogen that can jump from non-humans to humans\

Avian influenza

What are the 4 biosafety levels, and what risk level does each carry, and give an example of each.

BSL-1: Low risk (e.g., non-pathogenic E. coli)

BSL-2: Moderate risk (e.g., HIV)

BSL-3: Serious diseases via aerosols (e.g., anthrax)

BSL-4: High-risk, no treatment (e.g., Ebola)

What are the 3 high risk groups in clinical settings?

Researchers

lab techs

animal handlers

What is a sharps injury?

What are 2 ways can they be prevented?

A penetrating wound from an object like a needle, scalpel, or broken glass, which can risk exposure to blood-borne pathogens

(1) Using and handling sharps carefully

(2) Proper disposal of sharps

What are biosafety cabinets?

What are 4 transmission routes for disease?

Primary barrier against aerosol exposure.

(1) Vector 

(2) Fomite

(3) Droplet 

(4) Vector

What are the two types of personnel needed in an effective biosafety program?

Biosafety officer

Institutional Biosafety Committee (IBC)

What are Biological hazards (biohazards)?

Organisms or by-products that pose health risks