Sulphite (Sulfite) Test Kit indicator TK - 14 is a part of  RXSOL-62-5503-001.  This refil pack is very economical and available on 50% discount for our exhisting ustomer.
Role of TK - 14 during sulfite test procedure ::: 
Add  TK - 14 ::: RXSOL-62-5503-003 Powder a dipper at a time, swirling after each dipper, until color changes from red to colorless. Add 2 more dippers. Swirl until dissolved.  ( Note : Use the plastic dipper to add TK - 14 ::: RXSOL-62-5503-003 to the sample. Add only one measure at a time and stir thoroughly between each addition of TK - 14 ::: RXSOL-62-5503-003. All the particle of TK - 14 ::: RXSOL-62-5503-003 may not dissolve and this may create a slight haze in the sample. Continue to add the TK - 14  in this manner until the red color disappears. It is not necessary that the sample solution be exactly neutralized, only that the sample turn colorless. When the sample is colorless, add one additional measure of TK - 14 ::: RXSOL-62-5503-003 and stir. )

RXSOL-62-5503-001  is complete set to DETERMINE Sulfite label in feed Water.

Dose of Sulfite  can be controlled by this method :::  Because it readily reacts with oxygen to form sulfate, sulfite is not usually found in natural water systems. In its most common form, sodium sulfite, it is widely used as an oxygen scavenger in feedwater conditioning to prevent pitting in boilers; as a pulping or pulp-bleaching agent by the paper industry; to neutralize residual chlorine in potable water, sewage, industrial effluents, and textile process waters; and as a reducing agent in still other manufacturing processes. 

Sample water over 100°F will cause a false-high reading; therefore, quickly cool to room temperature before testing. To prevent a false-low reading caused by the reaction between sulfite and ambient air or dissolved oxygen, water samples should be capped while cooling and then tested without delay. An iodometric drop test is the most popular field method for determining sodium sulfite concentrations. 

Reagent packs, containing an instruction and chemicals only, may be purchased for use with buret setups. Note: Sulfide and ferrous iron cause positive interference; copper and nitrite cause negative interference.