Hazcat’s Cyanide Test –
• FINDS cyanide in substances with a pH of 0-14 (a cyanide mixed with a non-metallic acid precursor such as phosphorous pentoxide will have a pH of 0-1 but not release the cyanide until mixed with water)
– Some cyanide salts are insoluble in water or have a neutral pH. These cyanides still react with acids & are hazardous:
Copper-CN pH 7, mercuric-CN pH 8, silver-CN pH 8, zinc-CN pH 7
• FINDS cyanide in samples that test +ve as Oxidizers
– Other tests state: “Samples that test +ve oxidizer cannot contain “CN”. Not true. Oxidizers such as sodium hypochlorite & hydrogen peroxide convert cyanide to cyanate removing the “CN hazard” but many other oxidizers do not have that effect on cyanides.
– Oxidizers that can be mixed with CN salts without converting them to cyanates; whose mixtures are +ve Oxidizer include:
Sodium Percarbonate, Potassium Chlorate, Potassium Chromate & Copper Sulfate. Compounds such as copper-CN & chromium-CN give a +ve Oxidizer Test due to the metal
• HAS NO interferences, no false +ves, no false -ves
– Other tests have:
False +ves: Thiocyanates – sodium thiocyanate, potassium thiocyanate, mercury thiocyanate
False -ves: When cyanides are mixed with: bromide, iodide, chromate, permanganate, or strong reducing agent: tin chloride, sodium sulfite, sodium borohydride or zinc metal, a false -ve occurs
More False -ves: Copper cyanide, palladium cyanide, mercuric cyanide & silver cyanide give false -ves
• WORKS IN any matrix. If the cyanide is mixed with a paint, the test still works – it looks for hydrogen cyanide gas in the atmosphere above the sample. Other tests rely on color changes to strips of test paper immersed in the sample. If the matrix has a color, this can interfere with reading the test strip
• REQUIRES ONLY 1ml of liquid sample or ½ spoonful of solid sample. Other tests require 5ml of liquid sample & do not give instruction for solids
• HAZCAT’s reagents do not have a shelf life. Other tests use papers/reagents with expiration dates
Hazcat’s Sulfide Test –
• not dependent on matrix being tested
– finds H2S gas in the atmosphere above the sample
• gives a positive with a wide range of sulfide types
– will give a +ve with Acid-volatile sulfides: iron sulfides; FeS, Fe3S4, pyrrhotite, & monosulfides of other metals
– Copper & silver sulfides are so insoluble they don’t respond in other test methods; Hazcat’s sulfide test gives a +ve with these substances