Use of ammonia test tubes
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A safety analysis must be conducted during equipment maintenance; ammonia cannot be detected using ammonia test tubes, yet amine detectors indicate the presence of ammonia.
1. Detection limit range 2. Shelf life
Reply to 2# woonty: The detection limit is 200–2000 mg/m3, and the validity period is also good.
1. Try imported test tubes; domestic ones are unreliable. 2. Additionally, under normal circumstances, amine substances will interfere with ammonia test strips. 3. The detection range of the test tube mentioned by the poster is too large.
Reply to 4# lizhaoman: Those with a detection limit of 5–200 mg/m3 were also tried but didn’t work; it’s possible that domestic ones aren’t suitable
Reply to 5# jiaqirumeng2449: Try an even lower value. One model of our company is 0.05-1.0mg/m3.
Reply to 6# lizhaoman: The detector shows 1000PPM; values between 5-200mg/m3 are all too low, but it’s not possible to reduce the value any further. It shouldn’t be a problem with the detection limit.
Conversion between concentration units ppm and mg/m3: mg/m3 = M/22.4·ppm·*(Ba/101325). Here, M is the molecular weight of the gas; ppm is the measured volume concentration; T is the temperature; and Ba is the pressure. The value can be obtained by using this formula
Reply to 7# jiaqirumeng2449: It already smells bad at 1000 ppm. It is very harmful to the human body. Health standards: MAC(NH3) = 30 mg/m3, 44.11 ppm ； STEL(NH3)=35ppm IDLH(NH3)=300PPM Harm at ERPG concentrations (ppm) ERPG1: 25 – causes irritation ERPG2: 200 – can cause permanent damage ERPG3: 1000 – can be fatal
The key point: Did the analyst smell ammonia? 1000 ppm is a very high concentration.