San Francisco Fire DepartmentHearing Conservation Training

Shawn Holle, Safety AnalystCCSF Department of Public HealthOccupational Safety & Health Section

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Overview

Sound v Noise Ear Anatomy Cal-OSHA Regulations SFFD Hearing Conservation Program Evaluation Medical Surveillance Noise Control

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Sound v Noise

What’s The Difference Between Sound & Noise?

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Sound

Pressure Waves in AirWaves Have:

Physical Size Intensity (Frequency)

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How Do We Measure It?

Decibel (Db) Expresses Intensity of Sound Three Different Scales - A, B, & C

Hertz (Hz) Unit of Measurement for Sound Frequencies Human Hearing Ranges From 20 Hz & 20,000 Hz

High Frequency: Dog Whistle, Siren Low Frequency: Engine Idling, Bass Drum

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Typical Sound Levels

Decibel Level Examples

0 Quietest Sound One Can Hear

30 Whisper: Quiet Library

60 Normal Converstation, Sewing Machine, Typewriter

90 Lawnmower, Shop Tools, Truck Traffic (8 Hours Per Day Maximum Exposure)

100 Chain Saw, Pneumatic Drill, Snow Mobile (2 Hours Per Day Maximum Exposure)

115 Sandblasting, Rock Concert, Air Horn (15 Minute Per Day Maximum Exposure)

140 Shotgun, Jet Engine (Noise Causes Pain & Possible Exposure Injury)

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Fire Department Sound LevelsApproximate Decibel

Level Examples

73-120 Test Box

134 Air Horn (Morning Test)

112-117 Air Tank Bleed (4 Feet from Truck)

75-95 Engine Idling (Measured in Cab)

80-99 Engine Accelerating (Measured in Cab)

92-109 Air Horn (Measured in Cab)

104-108 Jaws of Life

93-104 Cement Cutter

103-105 Chainsaw

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Time Weighted Average (TWA)

Average Noise Level During 8-hour Period

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Hearing Loss TypesWhat Are Threshold Shifts?

Temporary Threshold Shift (TTS) Permanent Threshold Shift (PTS)

Change in Hearing Threshold Compared toBaseline Audiogram: Average of 10 Db or More inEither Ear At:

2000 Hz 3000 Hz 4000 Hz

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Indicative of noise exposure

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Human Ear:Anatomy & Mechanics

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Cochlea Contains Hair Cells Cells Can Be DestroyedDestroyed Cells Don’t GROW BACK

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Human Ear: Hair Cells

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Human Ear: Healthy Hair Cells

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Human Ear: Damaged Hair Cells

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Hearing Loss

Cumulative - Over Time Permanent Totally Preventable

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Hearing Loss:Important Factors

Genetics / Heredity Illness (Measles) Medications Trauma Pressure Changes Age Lifestyle

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Hearing Loss: Not Just At WorkNon-Occupational Noise

MusicGunsMotorcyclesMuscle CarsEtc.

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Hearing Loss: Important Factors

Hearing Can’t Be Turned On & Off Hearing Must Be Protected At All Times Workplace Standards

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Can I Toughen Up My Ears?

NO

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Firefighter Hearing Losses

8%

15%

22%

55%

Normal Hearing Mild High Frequency Hearing Loss

Moderate High Frequency Hearing Loss Severe High Frequency Hearing Loss

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Cal-OSHATitle 8: 5097 Hearing Conservation Standard

Noise Exposure Greater than 8 Hour TWA of 85 dBA to be Covered

Responsibilities Evaluation & Surveillance of Work Environment Medical Surveillance - Annual Tests Noise Control Methods Training Program Evaluation Recordkeeping

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Evaluation & SurveillanceWork Environment

Monitoring Results of Fire Stations Indicate Noise Levels on the Job Exceed 85 dBA Over 8 Hours

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Medical Surveillance

Annually Audiogram Results Available on Request

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Audiometric Test Results

Fire Fighters Notified of Standard Threshold Shift >10 dBA 25 dBA Loss Requires Doctor’s First Report (Work Comp) STS >10 dBA & Loss of 25 dBA Requires Retest OHS Keeps Permanent Records Abnormal Tests Submitted to Department Physician & Entered In

Medical Record

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Controlling Noise

Engineering, Administrative, PPENoise Reduction Rating (NRR)AttenuationFitting & Using Hearing ProtectionHearing Protection Maintenance

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Hearing Protection: PPEPlugs Baby

Noise Reduction Rating (NRR) Rates Noise Reduction Amount Provided by

Hearing ProtectionAttenuation

Estimated Sound Reduction Provided by Hearing Protection

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Demonstration: Wearing Hearing Protection

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Inspecting Hearing Protection

Small Holes (Let In High Frequency Noise) Cracks On Earmuff Covers Reduce Insulation

Effectiveness Oils, Dirt, Soot Degrade Protection Clean Regularly: Manufacturer Specifications Use Mild Soap & Water Solution

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Hearing Protection Mandatory

On All Department Vehicles Engines Running Fireboat Jaws of Life Jack Hammers Cement Cutters Outboard Motors Equipment Tested Outside Siren & Air Horn Testing Prohibited in Stations Officers Accountable for General Order

Compliance

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SFFD Hearing Protection

Earmuffs Canal Caps When Overhauling, Testing, Using

Equipment Disposal Plugs

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Personal Protective EquipmentHearing Protection

Supplemental Hearing Protection OK Lost Equipment Replaced at Employee Expense Firefighters Responsible for Hearing Protection

Maintenance

Heat Stress

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Overview

What Is Heat Stress? Normal Cooling Mechanisms First Aid Risk Factors & Evaluating Risk Prevention & Management Your Responsibility

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What Is Heat Stress?

Heat Buildup in Body Generated by Muscles During Work Coming From Hot & Warm Environments Happens When Heat Load Too High

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Normal Cooling Mechanisms

When Body Core Temperature Rises Increased Blood Flow to Skin Surfaces Increased Sweating Increased Heart Rate Increases

When This Works Well Core Temperature Drops or Stabilizes

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Body Core v Peripherals

Core: Heart, Lungs, & Other Vital Organs

Periphery: Extremities Core & Periphery Compete With

Each Other for Blood Supply

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When Cooling Mechanism Fails

Dehydration Results Body Cannot Cool Itself Core Temperature Rises Salt Loss Causes Heat Cramps Blood Flows to Periphery…Organs Shut Down

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Environmental / Task Factors Contributing to Heat Stress

Ambient Temperature > 75ºF ^Relative Humidity Sources of Heat (Fire) Clothing (Heat Entrapment / Weight) Workload Microenvironment Physical Fitness

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Heat Stress Categories

Categories: Heat Rash Sunburn Heat Strain / Cramps Heat Stress / Exhaustion Heat Stroke

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Heat Rash

Skin Irritation or EruptionsRed Clusters of Pimples or BlistersOccurs in Skin Creases

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Sun Burn

Premature Aging of Skin Skin Cancer (Melanoma) Symptoms Include:

Red Skin (Discomfort) Blisters (Infection) Fever (Thermo-Regulation) Pain (2º or 3º Burns)

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Heat Strain / Cramps

Involuntary Muscle Contractions Caused by Not Replacing Fluids or Electrolytes

Occurs Usually in the Legs or Abdomen, Which Warn That Heat Stress Is Developing

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Imbalance Between Heat Gain & Body Heat Loss Environmental & Workload Conditions Place

Excessive Demand on Temperature Regulation

Heat Stress / Exhaustion

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Heavy Sweating Pale Nausea & Vomiting Headache Blurred Vision Dizziness & Fainting More Susceptible

Heat Stress / Exhaustion Symptoms

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Heat Stroke

Body Unable to Control Temperature Oral Temperature Above 105 F in 10 to 15 Minutes Death or Permanent Damage If Untreated Heat Stroke Kills 4,000 Americans Annually

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Heat Stroke Symptoms

Oral Temperature Over 105FNo SweatingRed, Hot, Dry SkinThrobbing HeadacheDizzinessNauseaUnconsciousness

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Sunburn Treatment

Apply Cold Compresses to Burned Areas Apply Moisturizing Lotions to Affected Areas No Butter, Ointment, or Lard Do Not Break Blisters

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Heat Rash Treatment

Provide Cooler, Less Humid, Environment Keep Affected Areas Dry Apply Powder Avoid Ointments & Creams

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Heat StressFirst Aid

Cool Victim Rest in Cool Place Drink Cool Water Loosen Clothing Remove Unnecessary Clothing Shower or Sponge With Cool Water

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Heat StrokeFirst Aid

Immediate , Aggressive, Effective Cooling Immerse Victim in Tub of Cool Water Place in Cool Shower Spray With Cool Water From a Hose Wrap in Cool, Wet Sheet & Fan Rapidly

Nothing by Mouth – It Won’t Stay Down Transport to Hospital

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Risk Factors

Overweight Small Body Size Poor Nutrition Poor Physical Condition Previous Heat Illnesses

Lack of Acclimatization Over 40 Heart Disease High Blood Pressure Diabetes

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Risk Factors for Individuals

Recent Immunization Alcohol During Previous 24 Hours Medications That Limit Sweating Excessive Caffeine Intake Low-Salt Diet

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Weather

Temperatures Above 70F During the Day, 80F at Night

Direct Sunlight Can Equal an Increase up to 130F in Air Temperature

High Humidity Little Air Movement

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Job Risk Factors

Heavy Work Prolonged Shifts Heavy Clothing Protective Gear & Respirators Exposure to Any Toxic Agent

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Prevention & Management

Traditional Controls Clothing & Personal

Protective Equipment (PPE) Work Assignments, Work

Cycles Acclimatization Additional Controls

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Clothing & PPE

The More Clothing Worn, the Longer It Takes Evaporation to Cool the Skin

Coated & Non-woven Personal Protective Garments Block Evaporation of Sweat

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PPE Selection

Use Lightweight Garments & Respirators Light-Colored Garments Absorb Less

Heat From Sun Cooling Vests

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Work Rest Cycles

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Acclimatization

Increases the Amount of Sweat Produced Speeds Up Onset of Sweating Resets Internal Thermostat Regulates Content of Sweat to Conserve Electrolytes Increases Blood Flow to Extremities Reduces Heart Rate Burns Fat Conserves Carbohydrates Reduces Core & External Temperatures 7 to 10 Days to Achieve Lost in 2 to 3 Days

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Worker’s Responsibilities

Hydration Being Alert for Symptoms in Themselves & Others Getting Adequate Rest & Sleep Carrying Out Instructions & Training for

Controlling Heat Stress