Palintest Photometer Tablets 250s – DPD3

Description

Test Instructions

1. Rinse the test tube with the sample leaving a few drops of the sample in the tube.
2. Add and then crush, the DPD No 1 tablet in the few drops of the water sample until the tablet is thoroughly crushed.
3. Add the 10ml test solution, mix and seal the tube with the cap.
4. Select Photo 7 on Photometer.
5. Take the Photometer reading in the usual manner – see Photometer instructions.
6. The result represents the free chlorine residual in milligrams per litre (mg/l). Stop the test at this stage if only free chlorine determination is required.
7. If it is desired to measure combined or total chlorine residual continue the test on the same test portion. Select the ‘Follow On’ from the screen options to continue the
   test program.
8. If shock treatment chemicals are present in the pool, add one DPD Oxystop tablet, crush and mix to dissolve. Stand for one minute before proceeding.
9. Add one DPD No 3 tablet, crush and mix to dissolve.
10. Stand for two minutes to allow full-colour development.
11. Take photometer readings in the usual manner.
12. The result represents the total chlorine residual as milligrams per litre(mg/l).
13. The combined chlorine residual is obtained by subtracting the free chlorine from the residual result from the total chlorine residual result:- ie Combined Chlorine = Total Chlorine – Free Chlorine