Fluoride is one of the very few chemicals that have been shown to cause significant effects in people through drinking-water. Fluoride has beneficial effects on teeth at low concentrations in drinking-water, but excessive exposure to fluoride in drinking-water, or in combination with exposure to fluoride from other sources, can give rise to a number of adverse effects.
Water fluoridation is the controlled addition of fluoride to a public water supply to reduce tooth decay. Fluoridated water operates on tooth surfaces: in the mouth it creates low levels of fluoride in saliva, which reduces the rate at which tooth enamel demineralizes and increases the rate at which it remineralizes in the early stages of cavities.
A 1994 World Health Organization expert committee suggested a level of fluoride from 0.5 to 1.0 mg/L, depending on climate. Bottled water typically has unknown fluoride levels, and some domestic water filters remove some or all fluoride.
The HI 739 Checker®HC is simple to use. In one vial add 2 ml of Reagent A and 8 ml of Reagent B; gently invert 5 times, and wait 1 minute, then zero the instrument with the vial. After zeroing, remove the vial and add 1 ml of sample, gently invert 5 times, wait 1 minute, then insert the cuvette into the HI 739 Checker®HC and press the read button for results.
Manual: Download
Specification :
| Range | 0.0 to 20.0 ppm | |
| Resolution | 0.1 ppm | |
| Accuracy @ 25°C | ±0.5 ppm ± 5% of reading | |
| Light Source | LED @ 575 nm | |
| Light Detector | silicon photocell | |
| Environment | 0 to 50°C (32 to 122°F); RH max 95% non-condensing | |
| Battery Type | (1) 1.5V AAA | |
| Auto-off | after two minutes of non-use and ten seconds after reading | |
| Dimensions | 81.5 x 61 x 37.5 mm (3.2 x 2.4 x 1.5”) | |
| Weight | 64 g (2.25 oz.) | |
| Method | adaptation of SPADNS method |
เครื่องวัดคลอรีน
น้ำยามาตรฐานสอบเทียบ ค่ามาตรฐานความเค็ม
HI713 Checker HC ® - Phosphate, LR
HI716 Checker HC ® - Bromine
เครื่องวัดปริมาณซิลิกา ช่วงต่ำ ในตัวอย่างน้ำ รุ่น HI705
เครื่องวัดปริมาณคลอรีนรวม รุ่น HI711
FC232D - Foodcare pH-Elektrode für HI 99161, DIN, 1 m Kabel (Fleisch)
HI98128 pH/°C-Tester (0.01 pH resolution) - waterproof
เครื่องวัดปริมาณคลอรีนอิสระ รุ่น HI701
สารละลายมาตรฐานความขุ่น 20 NTU
HI96822 Seawater Analysis (Salinity) - Digital Refractometer Portable
HI3831T CTK Chlorine Total
HI727 Checker HC ® - Color of Water
เซ็นเซอร์วัดออกซิเจนในน้ำสำหรับ HI9829 มัลติพารามิเตอร์
HI708 Checker HC ® - Nitrite, HR
เครื่องควบคุมค่าความนำไฟฟ้า
HI3844 CTK Hydrogen Peroxide
HI764 Checker HC ® - Nitrite, ULR 

