Many factors affect the pH of skin, including age, genetics, sweat, and moisture. Skin has a naturally acidic pH, ranging from pH 4 to 6. However, continued effects of alkaline cosmetic products, soaps, and detergents can easily raise the skin’s natural pH. A higher-than-normal pH can lead to adverse skin conditions, so monitoring the biological compatibility between skin and cosmetics and pharmaceuticals is essential.
The HI99181 uses the HI14143/50 amplified pH electrode with glass body. This specialized electrode offers numerous features that improve surface pH testing. An integrated temperature sensor allows for temperature compensated pH measurements without the need for a separate temperature probe. The probe’s flat sensing tip provides optimal surface contact for skin measurement. An integral part of any pH electrode is the reference junction. The reference junction is a part of the electrode that allows for the flow of ions located in the reference cell into the sample being tested. It is vital that this flow occurs in order to complete an electrical circuit, which ultimately determines the pH value. Poor contact between the junction and sample will prevent completion of the circuit, resulting in readings that are erratic or constantly drifting. The flat tip of the HI14143/50 provides optimal surface contact between the sample and the junction. The HI14143/50 features an open junction design which utilizes a viscolene reference electrolyte that comes into direct contact with skin’s surface, providing accurate, stable readings.
Glass Body
The glass body of the HI14143/50 is chemically resistant and quick to reach thermal equilibrium, allowing for a faster, more stable response.
Flat Tip
The flat tip sensing bulb allows for the direct surface measurement of skin. Maximum surface contact is achieved with this specialized tip shape.
Open Junction Reference
The open junction design consists of a solid gel interface (viscolene) between the sample and internal Ag/AgCl reference. This interface not only prevents silver from entering the sample, but also makes it impermeable to clogging, resulting in a fast response and stable reading.
Built-in Temperature Sensor
Errors in calibration and measurement are eliminated with the Automatic Temperature Compensation provided by the integrated temperature sensor.
Features at-a-glance
Waterproof – The HI99181 is a waterproof meter rated IP67 for immersion in up to one meter of water for 30 minutes.
Automatic Calibration – One or two-point calibration is automatic to two selectable buffer sets.
Automatic Temperature Compensation – An integrated temperature sensor allows for automatic temperature compensation of pH measurements.
Sensor Check – Using the pH‐mV range the user can check the sensor status by reading the mV reading in fresh buffers. At room temperature (25 ℃/77℉) the reading should be ±30 mV in pH 7.01 and greater than 150 mV difference between pH 7.01 and 4.01.
Multi-Level LCD Display – The split-level LCD displays both pH and temperature readings, along with indicators for reading stability, battery percentage, and probe condition.
Probe Condition Indicator – The probe condition indicator is based on the offset and slope characteristic of the electrode. There are 5 bars ranging from all 5 indicating the probe is in excellent condition and 1 bar indicating the probe should be cleaned or replaced.
Battery Error Prevention System – The meter will automatically shut off if there isn’t enough power to obtain an accurate measurement.
Battery Life Indicator – The battery percent level is displayed at start up alerting the user to the remaining battery power that is available.
