Hydrogen Sulfide Hazard Assessment - PowerPoint PPT Presentation


PPT – Hydrogen Sulfide Hazard Assessment PowerPoint presentation | free to download - id: 6e031b-MDM3N


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation

Hydrogen Sulfide Hazard Assessment


Very brief exposures (seconds) to levels less than 100 ppm are less well understood. What is clear is that brief exposures above the TLV-TWA can be cited. – PowerPoint PPT presentation

Number of Views:27
Avg rating:3.0/5.0
Slides: 12
Provided by: verm47


Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Hydrogen Sulfide Hazard Assessment

Hydrogen Sulfide Hazard Assessment
  • Erik Vermulen
  • MSHA, District 9
  • Coal Safety and Health
  • 303-231-5586

Hydrogen Sulfide Hazard Assessment
  • Introduction
  • Occurrence in Mines, Scenarios
  • Detection
  • Range of Health Effects
  • Emergency Actions
  • Action Levels

Hydrogen Sulfide Hazard Assessment
  • Occurrence in Mines, Scenarios
  • Generated from reduced biomass (coal, natural
    gas, garbage), Geochemical sources in sediments,
    human metabolism
  • Released from pockets in coal, natural gas vents,
    supersaturated water
  • May be wide spread or localized constant or in
    pockets of varying concentration

Hydrogen Sulfide Hazard Assessment
  • Detection
  • Odor lt0.02 ppm none, 0.13 ppm perceptible,
    1.0 ppm - faint, 5 ppm - moderate, 25 ppm
    strong, 100 ppm lose odor in 2-15 minutes
  • Electro chemical sensors calibrated and within
  • Detector tubes and Impregnated Paper Within
  • Absorb air samples with analytical determination
  • Biological exposure methods for expired air and

Hydrogen Sulfide Hazard Assessment
  • Range of Health Effects
  • (Concentration Time Effects)
  • Death due to respiratory failure with brief
    exposures to very high concentrations (seconds at
    gt1000 ppm)
  • Acute intoxication with neurological,
    respiratory, ocular and cardiac symptoms with
    potential recovery (exposures from minutes to
    hours at 250 to 1000 ppm, in animals LC-50 ranges
    from 335 to 587 ppm)
  • Sub-Acute and Chronic toxicity include cardiac
    arrhythmia, neuropathology, respiratory
    lesions/edema, blood-enzymes, ocular, cellular
    effects (exposures from 10 200 ppm for hours to
  • Lifetime exposures Carcinogenic, developmental
    - none

Enforcement Surveys for H2S
  • Chapter 4, Health Inspection Procedures Handbook
  • Pre-inspection Actions Select method,
    pre-calibration, UMF
  • Walk-Through to document process, duration,
    frequency, sketch
  • Select maximally exposed occupation (if refuses
    can sample BZ)
  • Follow normal 8-hour, portal to portal sampling
  • Use Vent Plan method if one is designated, record
  • With instruments, check periodically, follow/note
    Manuf. instructions
  • Place instrument on shirt near breathing zone,
    note location
  • Recommend using a second detection method (stain
    tube, Zefluor tube, OSHA ID141) to verify, record
    sample time
  • Record miners locations, general duties,
    variance from normal
  • Fill out MSHA 2000-187 (MSHA 2000-194 if analysis

Enforcement Surveys for H2S Cont.
  • Out-brief miners/operators and notify that a
    citation may be issued if later data analysis
    indicates an over-exposure
  • If instrument TLV-TWA, 8Hr, exceeds 5 PPM notify
    operator that corrective action may be required
    no citation issued but Vent Plan change.
  • Post Inspection Actions
  • Post calibrate instrument or bump test
  • Download data using manufacturers software, save
  • Evaluated STEL file to see if any 15 minute
    increment gt 20PPM
  • Evaluate TLV file to see if 8 hour gt10 PPM
  • Contact District for assistance in writing the
    Citation, if applicable
  • (Note Instruments not listed by NIOSH or OSHA as
    standard method rationale important)

Hydrogen Sulfide Hazard Assessment
  • Range of Health Effects
  • (Receptor Susceptibility)
  • Health status and pre-existing pathology
  • asthmatics, heart patients
  • Concurrent exposures to organs (dust, CO, low 02)
  • Limited human data and uncertainty in applying
    animal data to human response
  • Small exposure range from no-effect to acute
    toxicity with uncertainty in epidemiological
    exposure levels

Hydrogen Sulfide Hazard Assessment
  • Emergency Actions
  • Explosive 4.3 to 46, Heavier than air
    evacuate and remove ignition sources, ventilate,
    water spray
  • Respiratory Hazard Use approved SCBA to rescue
    victims, if breathing apply 02, if not apply CPR,
    seek medical attention immediately, keep warm and
    calm, test atmosphere for toxic concentrations
  • Eye Irritant irrigate eyes with water if

Hydrogen Sulfide Hazard Assessment
  • Consensus Levels
  • MSHA TLV 10 ppm, Ventilation plan actions
  • 20 ppm for 15 minutes, allowable excursion
  • OSHA 20 ppm (C), 50 ppm _at_ 10 min. peak / 1/shift
  • ACGIH 10 ppm TLV-TWA, 15 STEL (NIC 1/5 ppm)
  • NIOSH IDLH 100 ppm (Imminent Danger)
  • AIHA ERPG3 100 ppm (60 min.) (life threatening)
  • ERPG2 30 ppm (60 min.) (serious /

Hydrogen Sulfide Hazard Assessment
  • Summary
  • Acute Risk Moderate to high respiratory
    failure, cardiac and neurological damage, ocular
  • Small range of significant effects many will
    tolerate 50 ppm some fatalities, many injuries
    at 500 ppm
  • Odor not dependable to detect use meters,
  • Use air supplied respirators for rescue Provide
    O2 / CPR
  • Explosive, may collect in low areas
  • Exposure concentrations may change without
    warning when low ventilation rates exist
  • Stay out Stay alive
About PowerShow.com