Background:Chlorine-containing disinfectants are widely used for disinfection in various water consumption fields. To inhibit the secondary multiplication of residul bacterium, viruses and other microbes, certain amount of free chlorine shall remain in the water some time after it is treated with chlorine-containing disinfectant, to ensure sustaining sterilization. However, excessive free chlorine content may very likely cause secondary water polution, often generating cancerogens and resulting in hemolytic anemia, a hazard to human health. Therefore, effective control and detection of water free chlorine content is critical to water treatment. As the traditional test method for free chlorine is complicated, the R&D team of Thaile Chemical has successfully developed “Thaile” free chlorine test kit for quick on-spot testing. The new test kit can greatly simplify the operation and significantly lower the testing cost with reliable testing result.
Principle:Testing based on DPD method of national standard.
Purpose:Quick and accurate test of water free chlorine content. On-spot quick test in various water consumption field, including industry, agriculture, aquiculture, healthcare, environment and domestic.
Features:
1.Quick and easy:No special training is required, as long as the user follows the instruction. It takes only 5 minutes to finish a test for one water sample.
2.Accurate and reliable:With test results equivalent to what national standard suggests, it is an alternative of the method introduced in the national standard.
3.Highly sensitive:The reagent is highly sensitive to free chlorine, with precision as high as 0.05mg/L.
4.Affordable: Cost per test is low.
5.Portable:Compact in size, lightweight, and suitable for on-spot quick test.
Operation:
1.Wash the colorimetric tube twice with water sample. Then, measure and take certain amount of water using the colorimetric tube. Adjust the level to the graduation mark of 15ml using a plastic dropper.
2. Ladle 1 flat ladle (use the colorimetric card to cut the powder so that it levels with the rim of the ladle) of Free Chlorine Test Reagent and add it into the colorimetric tube. Agitate the solution to make the powder dissove in the solution.
3. Start colorimetric test, after the powdered reagent dissolves, the process should be finished within 5 minutes. Vertically place the colorimetric tube 1cm above the blank area of the colormetric card and visually compare the colors from above. Read the free chlorine content of the water sample by finding the color code that appear the same color as that of the liquid in the tube.
Notes:
1.This product has a detectable free chlorine content range of 0.05-1.0mg/L. If the free chlorine content of the water sample is higher than the upper limite of the detectable range , dilute the water sample before testing.The actual result is obtained by timing the reading with corresponding dilution ratio.
2.If there are agglomerations in the powder, smash them with the ladle before using it. As the reagent is in excessive amount, small amount variation each time after cutting flat the powder will not affect the test result
3.If the water sample appear turbid, filter the sample , or stand the sample until it is clear, then take sample from the upper part, before testing.
4.The pH of the water sample shall be controlled in the range of 5-8.
5. The existence of other oxidants may interfere with this method.
6.Try to compare the colors in bright light.
7.In case of skin or eye contact of the reagent, just wash it away with water.
8.After use, please tighten the cap to avoid ineffectiveness. 　
Liability:The manufacturer and its authorized agents are free from any liabilities due to accidental intake of children and misunderstanding or misuse of the users. If the results of test are dubious, please present the sample to authoritative laboratory for further test.
Appearance: Free Chlorine Test Reagent: gray powder    
Specifications: Free Chlorine Test Reagent: 5g   (50 times per kit)
Including: Free Chlorine Test Reagent: 1 pc；   Colorimetric Tube: 1pc；   Plastic Dropper: 1 pc；   Ladle : 1pc；  
Colorimetric Card: 1 pc；   Users’Manual: 1 pc
Package:HDPE Bottle, Carton
Standard:QB-TCS-WTR-2011
Validity:1 year
Store:Store in a cool and shady place out of reach of children.
Manufacturer:Ningbo Thaile Chemical Technology Co., Ltd
Website: http://www.thaile.cn     http://nbtlhg.1688.com   

Related knowledge:
The forms in which chlorine exists in water:
Free chlorine : hypochloric acid, hypochlorite ions and dissolved free chlorine.
Combined chlorine: Chloramines and organic chloramines, as part of total chlorine.
Total chlorine: Coexisted free chlorine and combined chlorine.