Hazcat vs 5-Step – Comparisons
Testing for Cyanides:
• The 5-Step Kit only prompts the user to check for a cyanide compound when the pH of the unknown is 10-14. The Hazcat Kit prompts you to look for the cyanide anion in solids and liquids with a pH of 3-14
o There are several common cyanide salts that are either insoluble in water and/or have a neutral pH. Many of these cyanide salts are still reactive with acids and are still very hazardous. These hazards are not found by the 5-Step system.
These cyanide salts include copper cyanide (pH 7), mercuric cyanide (pH 8), silver cyanide (pH 8), zinc cyanide (pH 7)…
• The Hazcat Kit will look for the cyanide anion in samples that test positive in the Oxidizer Test. The 5-Step Kit states in it’s manual: “Samples that give a positive oxidizer test cannot contain cyanides.” This is not true. Certain oxidizers such as sodium hypochlorite and hydrogen peroxide will convert cyanides to cyanates which removes the “cyanide” hazard”, but there are many more oxidizers on the list of compounds that give a positive oxidizer test that do not have that effect on cyanides. Also, there are compounds such as copper cyanide, that all by itself gives a positive Oxidizer Test. Chromium cyanide also gives a positive Oxidizer Test due to the transition metal.
o Cyanide salts can also be mixed with several types of oxidizers without being oxidized to a cyanate. As such a sample could be positive oxidizer and still contain cyanides.
Compounds that give a positive Oxidizer Test, that can be mixed with a cyanide salt without any noticeable reaction, and whose mixture still gives a positive Oxidizer Test include:
• Sodium Percarbonate
• Potassium Chlorate
• Potassium Chromate
• Copper Sulfate
• The Hazcat Kit’s Cyanide Test 1 has no interferences, no false positives, no false negatives. The 5-Step Kit’s Cyanide Test has interferences that give false positives and false negatives:
o False Positive: Thiocyanates – sodium thiocyanate, potassium thiocyanate, mercury thiocyanate
o False Negative: When a cyanide is mixed with a: bromide, iodide, chromate, permanganate, or a strong reducing agent such as: tin chloride, sodium sulfite, sodium borohydride or zinc metal, a false negative may occur.
o More False Negatives: Copper cyanide, palladium cyanide, mercuric cyanide and silver cyanide can give a false negative.
• The Hazcat Kit’s Cyanide Test 1 will work in any matrix. If the cyanide compound is mixed with a paint or a dye, the test still works, because it looks for hydrogen cyanide gas in the atmosphere above the unknown. The 5-Step Kit relies on a color reaction (the appearance of a violet color) occurring on a strip of test paper that is immersed into the unknown. If the matrix is strongly colored or a paint then this can interfere with the ability to read a color change on the test strip.
• The Hazcat Kit’s Cyanide Test 1 requires only 1ml of a liquid unknown sample or ½ spoonful of a solid unknown sample. The 5-Step Kit requires 5ml of a liquid unknown sample and does not give instructions on how to test an unknown solid.
• The reagents used in Hazcat’s Cyanide Test 1 do not have a shelf life. The 5-Step Kit’s Cyanide Test has a 2½ year shelf life.
Hazcat vs 5-Step – Comparisons