Editing 2638: Extended NFPA Hazard Diamond

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The numbers in a normal NFPA 704 diamond do not specify values of substances' properties, but rather broad categories designating characteristics of the substances of greatest interest to {{w|first responders}} and hazardous materials cleanup crews. Randall's expanded diamond breaks with this convention, with several squares (Lilac, Orange, and Black) denoting absolute values, and one square (Green) denoting an economic value. This could very easily lead to documentation update headaches, especially since the Green square is mostly determined by supply and demand, and the Lilac square is linked to political outcomes. See explanation for each field in the extended square below in the [[#Table of extended diamond|table]].
 
The numbers in a normal NFPA 704 diamond do not specify values of substances' properties, but rather broad categories designating characteristics of the substances of greatest interest to {{w|first responders}} and hazardous materials cleanup crews. Randall's expanded diamond breaks with this convention, with several squares (Lilac, Orange, and Black) denoting absolute values, and one square (Green) denoting an economic value. This could very easily lead to documentation update headaches, especially since the Green square is mostly determined by supply and demand, and the Lilac square is linked to political outcomes. See explanation for each field in the extended square below in the [[#Table of extended diamond|table]].
  
The only easily identifiable substance which could likely meet the specific insignia numbers shown in the comic is {{w|thionyl chloride}} (SOCl<sub>2</sub>), a chlorinating reagent and solvent regulated as a chemical weapons precursor and sometimes used in the production of methamphetamine, which would also be represented with the '''<s>W</s>''' symbol inside the white square, indicating reactivity with water.
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The only easily identifiable substance which could likely meet the specific insignia numbers shown in the comic is {{w|thionyl chloride}} (SOCl<sub>2</sub>), a chlorinating reagent and solvent regulated as a chemical weapons precursor and sometimes used in the production of methamphetamine, which would also be represented with the '''<s>W</s>''' symbol inside the white square, indicating reactivity with water. <small>But if '''(Special Hazard)''' is the literal "Special Notice" classification in use then something far more exotic may be involved.</small>
  
 
The title text (which references "scary stories" of the Black square) refers to {{w|dimethylmercury}} and {{w|prions}}. Dimethylmercury, C<sub>2</sub>H<sub>6</sub>Hg, is an organic form of mercury with an NFPA score of 4-4-3 (contact can be fatal, will burn below 73° F (22 °C), will combust if put under pressure). In 1997, an American chemist, {{w|Karen Wetterhahn}}, died 298 days after a few drops of C<sub>2</sub>H<sub>6</sub>Hg on her latex gloves were absorbed into her hand through the gloves, causing fatal mercury poisoning. Despite her having followed all safety protocols of the time, it was not then understood that the chemical was so toxic, nor that latex was so permeable to it. Prions are misfolded proteins that are responsible for a number of neurodegenerative diseases, including {{w|mad cow disease}} and {{w|chronic wasting disease}} in non-human animals and {{w|Creutzfeldt-Jakob disease}} in humans. These would indeed be the kind of substances that would scare those working with them in their labs; if an accident occurred, the results could be calamitous. See for example the case of [https://arstechnica.com/science/2021/07/second-lab-worker-with-deadly-prion-disease-prompts-research-pause-in-france/ Émilie Jaumain], a lab technician who died after accidentally coming into contact with prions in mouse tissue.
 
The title text (which references "scary stories" of the Black square) refers to {{w|dimethylmercury}} and {{w|prions}}. Dimethylmercury, C<sub>2</sub>H<sub>6</sub>Hg, is an organic form of mercury with an NFPA score of 4-4-3 (contact can be fatal, will burn below 73° F (22 °C), will combust if put under pressure). In 1997, an American chemist, {{w|Karen Wetterhahn}}, died 298 days after a few drops of C<sub>2</sub>H<sub>6</sub>Hg on her latex gloves were absorbed into her hand through the gloves, causing fatal mercury poisoning. Despite her having followed all safety protocols of the time, it was not then understood that the chemical was so toxic, nor that latex was so permeable to it. Prions are misfolded proteins that are responsible for a number of neurodegenerative diseases, including {{w|mad cow disease}} and {{w|chronic wasting disease}} in non-human animals and {{w|Creutzfeldt-Jakob disease}} in humans. These would indeed be the kind of substances that would scare those working with them in their labs; if an accident occurred, the results could be calamitous. See for example the case of [https://arstechnica.com/science/2021/07/second-lab-worker-with-deadly-prion-disease-prompts-research-pause-in-france/ Émilie Jaumain], a lab technician who died after accidentally coming into contact with prions in mouse tissue.
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| Top Right || Yellow || Instability (2) || Denotes how stable the substance(s) are when exposed to water, heat, shock, air, or other substances. 2 indicates that "Normally unstable and will readily undergo violent decomposition but does not detonate. Also: may react violently with water or may form potentially explosive mixtures with water."
 
| Top Right || Yellow || Instability (2) || Denotes how stable the substance(s) are when exposed to water, heat, shock, air, or other substances. 2 indicates that "Normally unstable and will readily undergo violent decomposition but does not detonate. Also: may react violently with water or may form potentially explosive mixtures with water."
 
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| Center || White || (Special Hazard) || The standard's "Special Notice" field may contain a symbol denoting additional information about the substance(s), e.g., '''OX''' for {{w|oxidizer}}s, '''SA''' for simple {{w|asphyxiant}} gases such as nitrogen and helium, and <s>'''W'''</s> for substances which react dangerously with water.
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| Center || White || (Special Hazard) || The standard's "Special Notice" field may contain a symbol denoting additional information about the substance(s), e.g., '''OX''' for {{w|oxidizer}}s, '''SA''' for simple {{w|asphyxiant}} gases such as nitrogen and helium, and <s>'''W'''</s> for substances which react dangerously with water. <small>Since the other squares in Randall's diamond contain values instead of descriptions, "'''(Special Hazard)'''" could conceivably be the special notice symbol for the substance depicted, instead of a description of the square's purpose.</small>
 
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!colspan=5| After this point, all squares are made up by Randall.
 
!colspan=5| After this point, all squares are made up by Randall.

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