Hydrogen Cyanide

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Hydrogen Cyanide

• THE OTHER SILENT KILLER

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COURSE OBJECTIVES

• The goal of this program is to provide the
  learner with a thorough understanding of Hydrogen
  Cyanide including the following
• Awareness and Recognition
• Prevention
• Protection
• Detection
• Diagnosis Treatment

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COURSE CONTENTS

• Chemical Properties
• HCN and CO The Toxic Twins
• Literature Review
• Case Studies Research
• Columbia Fire Department
• Fort Worth, Texas
• Equipment
• Response Protocol
• Hands-on Training

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Would you work here without SCBA?
Chlorine Gas
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so then why do it here?
Benzopyrine
Ammonia
Methane
Dioxin
Formaldehyde
Ethylene
Chloromethane
Oxides of Nitrogen
Carbonyl Fluoride
Benzene
Phosgene
Carbon Dioxide
Carbon Monoxide
Furfural
Sulfur Dioxide
Bromomethane
PCBs
Hydrogen Cyanide
Hydrogen Sulfide
Acetic Acid
Alcohols
Acrolein
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Chemical Properties

• Physical Properties and Health Effects of
  Hydrogen Cyanide

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Properties of HCN

• Hydrogen cyanide is a chemical compound with
  chemical formula HCN. It is a colourless,
  extremely poisonous liquid that boils slightly
  above room temperature at 26 C (79 F).
• HCN has a faint, bitter, burnt almond-like odour
  that only some people are able to detect owing to
  a genetic trait. The volatile compound has been
  used as inhalation rodenticide and human poison.
  Cyanide ions interfere with iron-containing
  respiratory enzymes.
• http//en.wikipedia.org/wiki/Hydrogen_cyanide

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Properties of HCN Exposure Limits

• IDLH 50ppm (Carbon Monoxide is 1200ppm)
• NIOSH REL 5ppm (Carbon Monoxide is 25ppm)
• OSHA PEL 10ppm
• EPA AEGL 3 (Life threatening effects or death)
• 10 minutes 27ppm
• 30 minutes 21ppm
• EPA AEGL 2 (Long lasting effects or impairment)
• 10 minutes 17ppm
• 30 minutes 10 ppm

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Properties of HCN

• Extremely poisonous, Extremely flammable
• LEL 5.6 - UEL 40
• Vapour Density - 0.93 (slightly lighter than air)
• Vapour Pressure 630mmHg
• Molecular Weight 27.03
• Ionization Potential 13.6eV
• Odour Threshold 0.58ppm

Burnt almond odour. Firefighters will not be
able to smell HCN amongst burning materials. 40
of the population cannot smell HCN.
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Properties of HCN

• NIOSH Physical Dangers
• Hazardous concentrations may develop quickly in
  an enclosed environment or poorly ventilated
  areas
• Mixes well with air, explosive mixtures are
  easily formed
• 24 times more toxic than Carbon Monoxide
• Magnifies the toxicity of HCN when combined with
  CO (Toxic Twins)
• http//en.wikipedia.org/wiki/Hydrogen_cyanide

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Health Effects Signs Symptoms

• MODERATE EXPOSURE

• SERIOUS EXPOSURE

• Headache
• Confusion
• Anxiety
• Blurred vision
• Loss of judgment
• Increased respiratory rate

• Dyspnea
• Cardiac dysrhthmia
• Seizures
• Coma
• Death

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Health Effects

• Potential Symptoms Asphyxia and death at high
  levels, preceded by seizures, coma with abolished
  deep reflexes and dilated pupils, paralysis,
  weakness, dizziness, numbness, tremor, loss of
  visual acuity, headaches, nausea, vomiting, loss
  of appetite, weight loss, increased rate and
  depth of respiration, or slow and gasping
  respiration, eye irritation, rash, chemical burns
  on skin, enlargement of the thyroid gland. NIOSH

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Health Effects

• Long Term Effects/Repeated Exposures
• Respiratory problems
• Weakness
• Heart disease
• Heart attack
• Stroke
• Brain damage
• Thyroid cancer

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Health Effects

• Workers exposed to concentrations of 4-12ppm
  periodically over a period of 7 years showed an
  increase in symptoms of headache, weakness,
  irritation of throat, change in taste and smells,
  and nervous instability ACGIH 1991
• Workers exposed to low concentrations of Hydrogen
  Cyanide have developed enlarged thyroid glands
  NLM 1995

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Health Effects Signs Symptoms

• Exposure to smaller concentrations can initially
  cause respiratory activation (manifested by rapid
  breathing and tachycardia) in an attempt to
  compensate for lack of oxygen. Early
  manifestations include headache, anxiety, blurry
  vision, and loss of judgment. As cyanide
  accumulates further, signs and symptoms of
  poisoning reflect the effects of oxygen
  deprivation on the heart and brain. These include
  cardiac dysrhythmias, seizure, coma, and death.
• The time between exposure and incapacitation or
  death is typically minutes, but varies depending
  on the concentration of cyanide and other
  toxicants.
• OBrien, DJ, Walsh, DW, Cyanide and Smoke
  Inhalation, 2010

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HCN Reference Materials

• UN 1051, Class 6 (Subclass 3)
• ERG Guide 117 Gases Toxic Flammable
  (Extreme Hazard) (Initial Isolation Zone of 60M
  for a small release)
• NIOSH Pocket Guide Page 168
• NFPA 704 Health 4, Flammability 4, Reactivity 2

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Case Studies and Research

• Lets look at some of the current studies and
  stats regarding HCN

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Cyanide Poisoning of Providence RI Firefighters

• March 23rd 2006
• Firefighter Kenneth Baker was confirmed to have
  cyanide poisoning due to a fire call
• He suffered a heart attack and died at a
  structure fire later that same shift
• As a result, all FFs who were at the first call
  were tested
• 8 of 27 firefighters tested had high levels of
  HCN in their systems
• CLICK HERE FOR PROVIDENCE REPORT
• - review pages 2 3 of the report

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Thyroid Testing During Physicals

• Largo (FL) Fire Rescue Ultra Sound
• 8 employees with thyroid nodules, 2 resulted in
  cancer and 1 yet to be determined
• 1 aneurysm
• 1 70 blocked carotid arteries
• Las Vegas Fire Department
• 8 thyroid cancers
• 3 brain cancers

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Columbia Fire Department Study

• Eight month study monitoring CO and HCN at fire
  calls (approximately 40 structure fires)
• Found staggering results with extremely high HCN
  levels at calls
• Found no correlation between CO and HCN
  production
• Worst offenders for HCN production were
• Pot on a stove/cooking fires (average small
  kitchen fire produces 75ppm of HCN)
• Car fires
• Dumpster fires
• Overhaul operations

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Fort Worth Texas Test Burns

• Conducted open-air burn study to capture HCN
  levels off of different materials
• Significant levels obtained in an open-air
  environment
• Highest levels were recorded at incipient stages
  of fire production and during smoldering periods
• This study confirmed what was being readily
  assumed about HCN levels in air during fires
• CLICK HERE FOR THE FORT WORTH STUDY

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Prevention, Protection Detection

• Lets look at how we can protect ourselves from
  HCN exposure

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Prevention and Protection

• Most important prevention tool is AWARENESS we
  need to be educated on HCN
• Recognizing Signs Symptoms of exposure
• PPE (use cleaning)
• Monitoring for HCN
• Establishing action levels
• Reporting levels and exposures
• Decontamination procedures
• HCN Standard Operating Guideline (CLICK HERE FOR
  DRAFT SOG) PLEASE REVIEW

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Detection

• Sensit P100 Single Gas HCN detector
• Located on secondary vehicles
• To be used at all fire related calls
• Can be used to monitor the atmosphere at
  incidents as well as readings off of PPE

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Operational Implementation

• HCN air monitoring shall be conducted at all fire
  occurrences and will help determine
• Scene perimeter and the locations of rehab,
  accountability, other agencies, etc. (extremely
  valuable tool for the ISO)
• The need for on scene gear decontamination
  and/or replacement (worst offenders for HCN
  retention are balaclavas and helmet ear flaps)
• The severity of smoke inhalation cases for
  firefighters and civilians (signs and symptoms)
• When we can operate off-air at an occurrence
  (action levels)
• LETS DISCUSS EACH OF THESE POINTS IN DETAIL

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Review

• HCN is more dangerous than Carbon Monoxide
• The IDLH of CO is 1200 ppm, while the IDLH of HCN
  is 50 ppm
• Low CO levels present a false security to the
  presence of HCN
• HCN has a short half-life, this can make it
  difficult to fully diagnose the level of exposure
• Early detection is imperative to the safety of
  personnel
• HCN symptoms in lower level exposures are similar
  to heat related illness and CO poisoning

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Review cont..

• HCN symptoms in severe or acute cases mirror that
  of a heart attack
• More firefighter and civilian deaths are being
  linked to HCN poisoning
• Poor firefighter PPE usage leads to increased
  exposure of HCN and CO
• Wear your SCBA at all fire calls
• PROTECT YOURSELF!

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Additional Resources Info

• AFTERMATH VIDEO - CLICK HERE TO WATCH
• Very informative video about HCN exposure,
  repsonse and treatment
• 37 minutes long
• Smoke, Dr. David Penney CLICK HERE TO READ
• Cyanide and Modern Fires, EMD Serano
  Pharmaceuticals CLICK HERE TO READ

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Additional Resources Info

• www.firesmoke.org
• Great resource for HCN and smoke related material
• Articles
• Research studies
• Etc.
• Login to access all the available information
• Username joness_at_burlington.ca
• Password firefighter

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Final thought..
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How many of us have been somewhere like this?

• 38 PPM of HCN!
• Actual incident photo and monitoring
• results from Columbia FD Study