Knockdown Pattern (H2S)
Definition
The scene distribution of multiple H2S victims clustered at the entrance or access point of a confined space, as first responders and would-be rescuers are overcome in sequence. Pathognomonic for a confined-space H2S event.
Related terms
- Bitter-Almond Odour
- The characteristic smell of hydrogen cyanide, detectable at autopsy in approximately 40% of people (a genetically determined anosmia to HCN). Present in...
- Carboxyhaemoglobin (COHb)
- The compound formed when carbon monoxide binds to haemoglobin at the oxygen-binding site, with an affinity 200-250 times greater than oxygen. Produces...
- Cherry-Red Livor Mortis
- Bright pink-red post-mortem lividity produced by the spectral absorption shift of carboxyhaemoglobin; also seen in cyanide poisoning and hypothermia. Distinguished from natural...
- Co-Oximetry
- Spectrophotometric analysis of blood that simultaneously quantifies oxyhaemoglobin, deoxyhaemoglobin, carboxyhaemoglobin, methaemoglobin, sulphhaemoglobin, and total haemoglobin by their distinct absorption wavelengths. The primary...
- Cytochrome C Oxidase (Complex IV)
- The terminal electron acceptor in the mitochondrial respiratory chain, inhibited by both cyanide and hydrogen sulphide. Inhibition prevents oxidative phosphorylation and ATP...
- GC-FID
- Gas chromatography with flame ionisation detection. The standard analytical method for quantifying cyanide and methanol in blood and tissue specimens. Provides both...
- Sulphhaemoglobin (SHb)
- A modified haemoglobin species in which one or more pyrrole rings is sulphonated by reaction with hydrogen sulphide. Produces green-brown blood and...
Explained in
- Chemical Asphyxia: CO, Cyanide and Hydrogen SulphideThe scene distribution of multiple H2S victims clustered at the entrance or access point of a confined space, as first responders and would-be rescuers are ove...