Replenish the complete chlorine dioxide method.
Keep a working HI97738 chlorine dioxide setup supplied with its coordinated A/B/C/D reagent set. Choose HI93738-01 for 100 tests or HI93738-03 for 300. These refills are for chlorine dioxide measurement—not free chlorine, total chlorine or the separate rapid-method chlorine dioxide chemistry.
Official Hanna bottle reference photograph for HI93738. It does not show the full A/B/C/D set or imply that the set contains only one bottle.
Fit for the HI97738 method
Use the HI93738 family with the HI97738 chlorine dioxide photometer and its chlorophenol red method, covering 0.00 to 2.00 mg/L as ClO₂. Match both the parameter and method before ordering: the name chlorine alone is not a compatibility check.
What the refill supplies
Each selected pack supplies the coordinated chlorine dioxide reagent A, B, C and D chemistry for 100 or 300 completed tests. The test capacity is not a bottle count. The manufacturer’s bottle photograph is reference packaging, not a picture of every component in the full set.
How the chemistry is used
The chlorophenol red method uses a prepared blank and a separately reacted sample. A complete determination consumes 1 mL each of HI93738A-0, HI93738C-0 and HI93738D-0 across the two preparations, plus one packet of HI93738B-0 in the blank only. The powder is not added to both cylinders.
Choose a pack for your testing schedule
Choose 100 tests for a smaller replenishment or 300 for an established routine. Plan around prompt sample analysis and the supplied reagents’ expiration dates. Keep the blank and reacted-sample vessels clearly identified: swapping them changes the measurement, regardless of pack size.
Prepare the equipment separately
Have the HI97738 meter, two graduated mixing cylinders, a suitable 1 mL syringe and two clean cuvettes with caps and stoppers ready separately. The refill does not include these items or CAL Check standards. Do not replace the prepared blank with plain sample or add an extra pretreatment that is not part of the HI97738 A/B/C/D procedure.
Work through the measurement sequence
Prepare two mixing cylinders with 25 mL of sample each. Add 0.5 mL of A to each and invert to mix; add one B packet to cylinder 1 only and dissolve it to make the blank. Add 0.5 mL of C to each cylinder and mix, then 0.5 mL of D to each and mix again. Transfer 10 mL of the blank to cuvette 1 and zero; transfer 10 mL from cylinder 2 to a second cuvette and read. Follow the HI97738 manual or tutorial for the complete sequence.
Protect the sample and the result
Use water samples appropriate for the HI97738 method; strong oxidants may interfere. Analyze chlorine dioxide samples immediately after collection. If storage is necessary, the manual specifies a sealed dark glass bottle with minimal headspace and avoiding excessive heat above 25 °C, agitation and light. These instructions do not establish universal seawater suitability.
Frequently Asked Questions
What does a selected pack supply?
HI93738-01 supplies the A/B/C/D chlorine dioxide reagent chemistry for 100 tests; HI93738-03 supplies it for 300 tests. Both are complete method reagent refills, not meters, cuvette kits or individual component bottles.
Is this a free- or total-chlorine reagent?
No. It measures chlorine dioxide with the HI97738 chlorophenol red method. Do not substitute free chlorine, total chlorine or HI96779 rapid-method reagents merely because their parameter names contain chlorine.
What range and reporting basis does HI97738 use?
The HI97738 method covers 0.00 to 2.00 mg/L as ClO₂. The larger pack changes test capacity, not the instrument’s measuring range.
Why are two sample preparations needed?
Both cylinders start with 25 mL of sample and receive 0.5 mL each of A, C and D in the specified sequence. Only cylinder 1 receives the B powder packet, making the blank. Zero with 10 mL of that blank, then read 10 mL from cylinder 2.
Do I add a separate glycine pretreatment?
The linked HI97738 chlorophenol red procedure specifies HI93738A-0, HI93738B-0, HI93738C-0 and HI93738D-0; it does not specify a separate glycine addition. Follow that exact A/B/C/D procedure rather than borrowing pretreatment steps from another chlorine dioxide method.
How should I collect and hold a sample?
Use water samples appropriate for the HI97738 method; strong oxidants may interfere. Analyze chlorine dioxide samples immediately after collection. If storage is necessary, the manual specifies a sealed dark glass bottle with minimal headspace and avoiding excessive heat above 25 °C, agitation and light. These instructions do not establish universal seawater suitability.
What must I have separately?
Have the HI97738 meter, two graduated mixing cylinders, a suitable 1 mL syringe and two clean cuvettes with caps and stoppers ready separately. The refill does not include these items or CAL Check standards. Do not replace the prepared blank with plain sample or add an extra pretreatment that is not part of the HI97738 A/B/C/D procedure.
Which other meters list this chemistry?
Hanna exact-model manuals also list HI93738 packs for HI83300, HI83305, HI83326 and HI83399. Use the chlorine dioxide method in the manual for that instrument. Review the four component-specific US Safety Data Sheets before handling the set.
