Problem: There is no longer a routine call. Recognize that every response is unique and should be treated as such. Always wear proper PPE and SCBA.
Mixing household chemicals to create toxic vapors:
- Look for and recognize containers that may indicate presence of common household chemicals
In most cases, two (or more) chemicals will be mixed to produce vapors.
Analyze the Problem
Recognition/ID and Warning Signs:
- Open containers or a ‘mixing container’. Chemicals may not be properly marked/labeled
- Do NOT rely on suicide notes or placards near the entry pathway for first responders which warn of danger
- Open containers or household chemicals where they would not normally be found (vehicles, bedrooms, etc.)
- Taping of doors, windows, dash vents, openings or other attempts to seal the enclosure
- Locations: Vehicles and Structures:
- If this is a chemical suicide remember it is a crime scene and needs to be treated as such
- Look for indicators in the surrounding area and question occupants. After analysis, vehicles and structures can be ventilated. Do NOT rely on presence or lack of chemical/unusual odors. Be aware of contact with liquids or powders and provide decontamination for occupants and responders.
Plan the Response
Take time to look into the vehicle for signs of a suicide (mixing vessels, residue, containers)
Response Options:
- Rescue/Recovery
- Evacuation/Isolation
- Protective handline
- Decontamination
- Preserve evidence
Selection of PPE:
- Follow FCE FOG for proper PPE and respiratory protection selection
Obtain control of air monitoring equipment
Selection of Decontamination
- Technical decontamination should be established for entry teams conducting control tasks
Plan of Action
- Use a Risk Based Response control plan
- Vehicle vs. Structure
- Compartment size will/can play a role in the levels of concentration, resulting in varying levels
- The smaller the compartment the higher the concentration -> higher toxic levels and potential to reach LEL levels
- Ventilate all occupancies to change the concentration levels of the environment
- Open the doors to vent
Implement the Plan
Fire Department Handline (vapor disbursement or extinguishment)
- Vapor Disbursement – Use water spray to reduce vapors or divert vapor cloud drift. Make sure to control and isolate runoff
- Extinguishment – May form explosive mixtures with air. May be ignited by heat, sparks or flames
Ventilation/Change the Environment – Properly trained and equipped first responders should ventilate after a thorough analysis of potential hazards
Air monitoring – Should be conducted throughout the incident and until evidence has been collected
Decontamination – All entry team members should undergo a technical decon. Beware of potential for occupants and clothing to ‘off-gas’ trapped vapors. EMS and the hospital must be notified in advance in order to avoid contamination of personnel/equipment
Crime scene considerations – Minimize responder exposure while preserving evidence
Evaluate:
- Maintain Situational Awareness – Don’t count on warning signs. Be aware of secondary contamination
Hydrogen Sulfide
Description | Colorless gas | Odor threshold | 0.77 ppm |
Molecular formula | H₂S | Odor description | Rotten egg |
Molecular weight | 34.08 | Exposure route | Inhalation |
Density | 1.19 (≈ 20% heavier than air) | Signs & symptoms | Irritation of respiratory system & eyes, apnea, coma |
Auto ignition temperature | 260°C (500°F) | LEL/UEL | 4%, 44% |
Vapor pressure | 15, 600 mm Hg @ 25°C (77°F) | IDLH | 100 ppm |
Solubility | Soluble in water, hydrocarbon solvents, ether and ethanol |
Detection | PID with 10.6 eV lamp |
Notes | Death by inhalation can occur quickly at low levels |
Hydrogen Cyanide
Description | Bluish-white liquid/colorless gas | Odor threshold | 0.58 ppm |
Molecular formula | HCN | Odor description | Bitter almond (odor may not be detected by smell) |
Molecular weight | 27.03 | Exposure route | Inhalation, absorption |
Density | 0.94 (lighter than air) | Signs & symptoms | Respiration/depth change, confusion, asphyxia |
Auto ignition temperature | 538°C (1000°F) | LEL/UEL | 5.6%, 40% |
Vapor pressure | 630 mm Hg @ 20°C (68°F) | IDLH | 50 ppm |
Solubility | Miscible in water, alcohol, slightly soluble in ether |
Detection | PID with 13.6 eV lamp |
Notes | Death by inhalation can occur quickly at low levels |