Keep ISO medium-range COD work on the right scale.
Refill your established chemical oxygen demand workflow with 25 pre-dosed HI93754G-25 reagent vials. The exact ISO reagent instructions and HI97106, HI83314 and HI83399 methods specify 0–1000 mg/L as O₂ for this formulation—not the higher range used by other medium-range COD reagents.
Official Hanna HI93754G-25 reference pack. Printed lot and expiration information illustrate packaging, not a guarantee for supplied stock.
Check the exact catalog number and method
Use the exact HI93754G-25 ISO 15705:2002 method on HI97106, HI83314 or HI83399. Confirm the instrument method, required vial adapter and digestion equipment before ordering; a generic COD MR label is not enough to establish reagent interchangeability.
What one pack supplies
One sellable pack contains 25 ready-to-use, pre-dosed reagent vials. Each initial determination workflow needs a sample vial and a reagent blank vial. This is a nominal vial count, not a promise of 25 reportable sample results: blanks, QC, repeats and any extra measurement sets consume additional vials.
Plan the digestion before starting
The documented procedure uses 2.0 mL sample and 2.0 mL deionized water in separate reagent vials, followed by digestion at 150 °C for 120 minutes. Follow the complete model-specific instructions for mixing, heating, cooling and optical reading. Use the required adapter for your exact instrument, and never insert hot vials into it.
Make the blank part of your method
Prepare blank and sample from the same reagent lot. The manuals allow reuse of an appropriately prepared same-lot blank and recommend a fresh blank for each measurement set for improved accuracy. Keep its identity and preparation records; do not treat an old blank from another lot as an interchangeable zero.
Check the sample matrix and reporting requirement
The ISO instructions specify chloride below 2000 mg/L; follow their dilution instructions for higher concentrations and account for dilution when reporting the sample. Homogenize samples with settling solids as instructed. Method fit does not establish universal EPA approval or acceptance for every permit or reporting program.
Handle, store and ship as hazardous chemistry
The US HI93754G-0 component SDS identifies sulfuric acid, dichromate, silver sulfate and mercury(II) sulfate. This is not a mercury-free refill. Use the prescribed PPE and handling controls, keep unused vials in their packaging in a cool, dark place, and arrange compliant spent-reagent disposal. The US product is classified as Dangerous Goods and ships by ground only; no delivery date is promised.
Frequently Asked Questions
What is the correct HI93754G-25 range?
0–1000 mg/L as O₂. The exact ISO instructions and all three referenced instrument methods take priority over conflicting generic retailer prose or comparison tables.
Does 25 vials mean 25 reportable samples?
No. A reagent blank consumes a vial, and additional blanks, QC and repeats use more. Plan your sample throughput from the complete method rather than the nominal pack count.
Which photometers have a documented method?
HI97106, HI83314 and HI83399 have specific HI93754G-25 procedures. Confirm the exact COD program and required adapter in your model manual; this is not a universal photometer refill.
What sample and digestion steps must I plan for?
The method calls for 2.0 mL sample, a separate 2.0 mL deionized-water reagent blank, and digestion at 150 °C for 120 minutes. Use the full instructions for safe mixing, cooling and reading.
Can I reuse a blank from another reagent lot?
No. Blank and sample must use the same reagent lot. Follow the manual’s blank reuse conditions and run a blank for each measurement set for improved accuracy.
Is this mercury-free or universally EPA approved?
Neither claim is appropriate. The actual component SDS lists mercury(II) sulfate; this is the ISO 15705:2002 formulation. Confirm acceptance for your own reporting program.
Can I test a high-chloride or settling sample directly?
Check the exact method first. ISO instructions require chloride below 2000 mg/L and direct dilution when higher. Homogenize settling solids as instructed; include dilution factors and validated QC.
How should I order and store this pack?
Order HI93754G-25 as one pack of 25 vials, not individual tests. Ground-only Dangerous Goods handling applies. Keep unused vials cool and dark in their packaging and use supplied-lot expiry information; the reference photo does not establish shelf life.
