Hanna Instruments

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Certificates of Analysis

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HI-50004-02 pH 4.00 Technical Buffer Solution, 25 x 20ml Sachets + / - 0.01 pH & cert

HI-50004-02 pH 4.00 Technical Buffer Solution, 25 x 20ml Sachets + / - 0.01 pH & cert

Hanna HI-50004-02 pH 4.00 Technical Buffer Solution, 25 x 20ml Sachets + / - 0.01 pH & cert

HI-50004-02 pH 4.00 Technical Buffer Solution, 25 x 20ml Sachets + / - 0.01 pH & cert

In Stock
£42.20 (exc. VAT) £50.64 (inc. VAT)

Designed and manufactured for those requiring a greater spectrum, as well as increased accuracy to readings, Hanna manufactures a Technical Buffer solution range that shares the accuracy of standard buffers, +/- 0.01 @ 25◦C, and features 20 pH levels, from pH1.00 through to pH13.00, effectively covering every point on the pH scale.

Technical Buffer Solutions are available in 500ml, 1 litre, 1 Gallon*, and handy 20ml sachets in packs of 10 or 25 for on-site or field use. The sachet single dose is safe, easy to carry and remains fresh.

Technical buffer solutions come with a certificate of analysis on purchase.

*One Gallon, colour-coded bottles are available in pH 4.01, pH7.01 and 10.01.

HI-50004-02 pH 4.00 Technical Buffer Solution, 25 x 20ml Sachets + / - 0.01 pH & cert information

Hanna's extended description

HI-50004-02 pH4.01 Technical Buffer Solution, 25 x 20ml sachets

HI-50004-02 is a premium quality pH 4.01 Technical buffer solution, National Institute of Standards and Technology (NIST) traceable and supplied with a Certificate of Analysis.

One of the most commonly used buffer solutions, it is extremely stable and represents the mid-way point in the acid range of the pH scale - ideal for those requiring an accurate acid reading, particularly those working in water purification plants, the food industry, and wherever the pH is expected to be acidic.

The single dose sachets are really handy with each sealed sachet holding just the right amount of solution. Each time a meter or electrode is calibrated using a Hanna sachet, it is like using a newly opened bottle of solution!

Benefits of individual packaging

  • Ideal for users who do not calibrate frequently
  • Ideal for field use due to portability
  • Every sachet is as fresh as the day it was packaged
  • Light block packaging prevents oxidation from UV light that could alter the buffer value.

Buffer solutions should be stored at 25 C, away from direct sunlight for accurate readings.

To correctly maintain your meter/electrode, we highly recommend use of a Hanna cleaning solution, as well as a buffer, for maximum performance every time.

Hanna buffer solutions are prepared, ready-to-use, according to precise formulas and standardised in accordance with the National Institute of Standards and Technology (NIST) to ensure quality and accuracy. All solutions show a batch number, an expiry date, and the correlation table between pH and temperature. All bottled solutions are sealed with an air tight, tamper-proof seal to prevent any Carbon Dioxide from entering and causing a change in the pH buffer value.

Browse the Hanna complete range of solutions

  • pH buffer solutions
  • Standard solutions for conductivity, Total Dissolved Solids (TDS), turbidity, salinity and Ion-Selective Electrode (ISE) calibration
  • Oxidation Reduction Potential (ORP) test and pre-treatment solutions
  • Reference fill solutions for refillable electrodes
  • General and specific cleaning solutions for electrodes
  • Solutions for electrode maintenance and storage
  • Solutions for sample preparation

Solutions are available in many sizes ranging from 20ml sachets for small users to 3.78L (1 gallon) containers for large quantity usage in laboratories.

For safety and traceability, all Hanna solutions are provided with a label showing the batch number and expiry date. A certificate of analysis is available on request in line with NIST standards.


  • Calibration only counts when using fresh solutions and properly cleaned electrodes every time.
  • Routine maintenance will ensure accurate readings while extending the life of the electrode.

Solutions are available in a variety of sizes. Check whether the solution you require is available in 1 gallon, 500ml, or 230ml bottles, or individual 20ml sachets.


Specifications list


pH value at 25°C 4.01
Code HI-50004-02
Package 20ml x 25
Certificate of Analysis Yes

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