We need phosphine detector for our grain silo, how to choose the right model of phosphine detector, please recommend!

Phosphine is a colorless, highly toxic gas, national standard: 0.3mg/m3, inhalation of phosphine will affect the heart, respiratory system, kidneys, stomach and intestines, nervous system and liver.

Selection of phosphine detector:

1, fixed phosphine alarm AP-G-PH3:

Fixed installation online monitoring, explosion-proof

Detection principle: electrochemical,

Range: 0-1,5,10,100,1000,4000ppm

Power supply: 24VDC, Output: 4-20MA,RS-485+2 groups of relays

Large screen display, infrared remote control operation

Explosion-proof audible and visual alarm, 2 levels of audible and visual alarm

Detection mode: diffusion, pipeline, flow-through

2, handheld phosphine detector AP-S-PH3:

Handheld Pump Suction detection

Detection principle: electrochemical,

Range: 0-1,5,10,100,1000,4000ppm

Large-screen display, large-capacity battery power supply

Storage function (can store 30 data)

Two levels of audible and visual alarm

3, Portable Phosphine detector AP- B-PH3:

Portable pump suction detection, handle type, high power air pump

Detection principle: electrochemical,

Range: 0-1,5,10,100,1000,4000ppm

Large screen display, large capacity battery power supply

Memory function (can store 30 pieces of data)

Two-stage audible and visual alarm