甲醛HCHO氣體檢測管171SA FORMALDEHYDE 20-1500ppm
Tube 71SA
1. PERFORMANCE
1) Measuring range :20-1,500 ppm
Number of pump strokes 1(100ml)
2) Sampling time :1.5 minutes /1 pump stroke
3) Detectable limit :5 ppm
4) Shelf life :2 years(Necessary to store in a refrigerated place ; 0~10℃)
5) Operating temperature :0~40℃
6) Temperature compensation :Necessary(See "TEMPERATURE CORRECTION TABLE")
7) Reading :Direct reading from the scale calibrated by 1 pump stroke
8) Colour change :Yellow→Pink
2. RELATIVE STANDARD DEVIATION
RSD-low:10% RSD-mid.:10% RSD-high:10%
3. CHEMICAL REACTION
By reacting with Hydroxylamine phosphate, Phosphoric acid is liberated and PH indicator is discoloured.
HCHO+(NH2OH)3?H3PO4→H3PO4+HCH=NOH+H2O
4. CALIBRATION OF THE TUBE
COLOURIMETRY METHOD
5. INTERFERENCE AND CROSS SENSITIVITY
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GAS To pump
DETECTOR TUBE
(white)
DEHUMIDIFIER TUBE
1500
1000
800
600
400
200
100
50
20
ppm
171SA FORMALDEHYDE
Substance Interference ppm Coexistence
Other Aldehydes Similar stain is produced. Higher readings are given.
Ketones 〃〃
Formal-
Methanol dcoenhcy.de Lower readings are given.
×1/2
TEMPERATURE CORRECTION TABLE
Scale True Concentration (ppm)
Readings 0℃ 10℃ 20℃ 25℃ 30℃ 35℃ 40℃
(ppm) (32°F) (50°F) (68°F) (77°F) (86°F) (95°F) (104°F)
1,500 - - 1,500 900 690 530 410
1,000 - - 1,000 700 550 430 340
800 - 1,300 800 600 490 390 300
600 1,200 900 600 490 410 330 250
400 600 520 400 350 290 230 180
200 240 230 200 180 150 130 100
130 100 100 100 90 80 70 60
50 50 50 50 45 40 35 30
20 20 20 20 20 20 20 20