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BTMETER · BTMETER BT-5800G Ammonia Gas Detector Sensor, Test for 0~100 PPM Nh3 Monitor Gauge with Temperature Humidity Tester
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The BT-5800G is the ammonia specialist in this group. It reads 0 to 100 ppm of NH3 with 0.1 ppm resolution and a stated accuracy of plus or minus 2 percent, and it adds ambient temperature and humidity because warm, humid air tends to produce ammonia faster. It is not a substitute for the Leakbee RV Propane propane alarm, the Aituzero Refrigerant Leak refrigerant sniffer or the HAOKESITE 0100ppm hydrogen sulfide clip, each of which targets a different gas. If your question is specifically about ammonia in a poultry house, stable or similar space, and you want a number rather than a yes or no, this is the instrument the listing describes.
Where the BT-5800G sits beside the other gas tools on this site
The site already covers three gas instruments that a reader might confuse with this one. The Leakbee RV Propane is a hardwired propane detector for recreational vehicles, built to sit in one place and alarm. The Aituzero Refrigerant Leak is a refrigerant leak detector for HVAC work, built to sweep a joint or a coil and find where a charge is escaping. The HAOKESITE 0100ppm is a clip-on hydrogen sulfide monitor for personal protection. None of them measures ammonia, and the BT-5800G does not measure propane, refrigerant or hydrogen sulfide.
That matters because the word detector is used loosely. The BT-5800G is a meter first: it puts a number on the display, and the alarm is a secondary function with two adjustable thresholds. The Leakbee RV Propane is an alarm first and does not publish a ppm reading. The Aituzero Refrigerant Leak is a search tool and does not publish a range in the supplied data. The HAOKESITE 0100ppm is a personal monitor for a different gas. Choosing between them is choosing which gas you are worried about, not which instrument is better. For the wider picture, see gas detector sensor types.
The 0 to 100 ppm range and what 0.1 ppm resolution buys you
Ammonia in livestock buildings is usually discussed in parts per million, and the BT-5800G is built around that unit. The listing gives a range of 0 to 100 ppm, a resolution of 0.1 ppm and an accuracy of plus or minus 2 percent. Resolution is the smallest change the display will show; accuracy is how close the reading is to the true value. A 0.1 ppm display on a 100 ppm range is a fine step, and it is useful when you are watching a slow rise overnight rather than checking a single moment.
The plus or minus 2 percent figure is stated without a reference point, so it is not clear whether it is two percent of the reading or two percent of full scale. On a 100 ppm range, two percent of full scale would be 2 ppm, which is a different proposition from two percent of a 10 ppm reading. The listing does not resolve this, and a buyer who needs a tight uncertainty budget should ask the manufacturer before relying on the number. What the listing does publish is the sensor type: an electrochemical cell. That is the same family used in many portable toxic-gas meters, and it explains why the instrument is single-gas rather than a four-gas box.
The temperature channel covers -10 to 50 degrees Celsius and switches between Celsius and Fahrenheit. Humidity is listed as a feature but the listing does not publish a humidity range or accuracy. That silence matters if you intend to use the humidity reading as a record rather than a hint.
Why temperature and humidity share the display with the ammonia reading
The listing makes a simple argument: in a warm, humid environment, ammonia is produced faster, so you should track temperature and humidity while you track the gas. That is a reasonable field rule. In a poultry house or a stable, the same litter or bedding that generates ammonia does so faster as temperature and moisture rise, so a ppm reading taken at one temperature is not directly comparable with a reading taken at another. Having all three numbers on one screen lets you note the conditions alongside the gas value.
What the listing does not publish is how the humidity sensor is specified, whether it is capacitive or resistive, or how often the display updates. If you need a calibrated humidity record for a compliance file, a dedicated logger from our temperature and humidity monitors roundup is the better instrument. The BT-5800G’s humidity channel is a context reading, not a reference measurement.
The tripod mount and the continuous-measurement claim
The listing describes a tripod mount port so the meter can be fixed in place and measure ammonia continuously at the same spot. That is the most useful line in the bullet text, because a handheld spot check tells you what the air was like for the few seconds the meter was in your hand. A fixed meter on a tripod tells you what happened overnight, when ventilation is lowest and ammonia tends to peak.
Two cautions follow from the listing itself. First, continuous measurement drains a battery, and the listing offers auto or manual power off to save it. A meter that powers itself off is not a continuous logger unless you disable that behaviour, and the listing does not say whether the auto-off can be turned off entirely or only postponed. Second, the listing does not publish a logging interval, memory capacity or export format. So the tripod mount gives you a stationary display, not necessarily a record you can download. If you need a file, plan to read the screen and write the number down, or pair the meter with a separate logger.
The two alarm limits, the buzzer, and what this device does not do
The BT-5800G has two adjustable alarm limits, AL1 and AL2. A slow flash and buzzer means AL1; a rapid flash and buzzer means AL2. That is a two-stage warning, which is more than a single-threshold beeper gives you. The listing does not publish the factory default values, the adjustment range, or whether the buzzer can be muted. Set the limits deliberately before you rely on them, and check that the values you choose are inside the 0 to 100 ppm range.
It is equally important to say what the instrument is not. It is a single-gas ammonia meter. It does not detect carbon monoxide, combustible gas, hydrogen sulfide or refrigerant. It is not a confined-space entry monitor, and it does not replace a four-gas detector with an oxygen cell. The listing calls it a portable ammonia detector, and that is the correct scope. For the distinction between a meter and an alarm, see what ppm means on a gas detector.
Charging, storage and the maintenance the listing leaves open
The meter is rechargeable through an included USB cable, with a green and red charging indicator and a remaining-power indicator. That is convenient, but electrochemical ammonia sensors have a known behaviour: they can drift and they have a finite life. The listing does not publish a calibration interval, a sensor replacement schedule, or whether the sensor is field-replaceable. Those are the questions to ask before you depend on the number for safety or for a compliance record.
The listing also does not publish an ingress protection rating. Ammonia is often measured in wet, dusty agricultural buildings, so a housing rating would be useful and its absence is a real gap. The storage case is listed, which helps in transit, but it is not a substitute for a stated IP rating. If you plan to use the meter in wash-down areas, treat the missing rating as a limit on where you take it. Our guide to test frequency covers the general routine; the specific interval for this sensor is not in the listing.
The verdict on the BT-5800G
The BT-5800G is a focused instrument: one gas, a fine resolution, two alarm stages and a tripod mount that lets it sit still and watch. It is the right choice when ammonia is the specific question and you want a ppm number rather than an alarm. It is the wrong choice if you need multi-gas protection, a certified confined-space monitor, or a logged data file, because the listing does not publish those capabilities. Buy it for the ammonia channel and the form factor; verify calibration and housing protection with the manufacturer before you make it part of a safety procedure.
Recommended Tools
Products shown because their documented specifications fit this guide. Price and availability are on Amazon and can change.
Frequently Asked Questions
Does the BT-5800G detect any gas other than ammonia?
No. The listing describes an ammonia gas detector with an electrochemical cell sensor for NH3. It does not list carbon monoxide, combustible gas, hydrogen sulfide or refrigerant detection. For those gases, look at the other instruments on this site, such as the Leakbee RV Propane for propane or the HAOKESITE 0100ppm for hydrogen sulfide.
What does the plus or minus 2 percent accuracy actually mean?
The listing states accuracy of plus or minus 2 percent but does not say whether that is of the reading or of full scale. On a 100 ppm range the difference is significant, so ask the manufacturer for the reference condition before you use the number in a report.
Can I leave it on a tripod to record ammonia overnight?
The listing provides a tripod mount for continuous measurement and an auto or manual power off option. It does not publish a logging interval, memory or export, so the tripod gives you a stationary display rather than a downloadable record. Check whether auto-off can be disabled if you need it to stay on.
Is the humidity reading accurate enough to log?
The listing names humidity as a feature but does not publish a humidity range or accuracy. Treat it as a context reading alongside the ammonia value, not as a calibrated humidity record. A dedicated humidity logger is the better tool for that.
What are the factory alarm limits?
Not stated in the listing bullets. The listing says AL1 and AL2 are adjustable and describes the slow flash and buzzer for AL1 and the rapid flash and buzzer for AL2, but it does not give default values or the adjustment range. Set them yourself before use.
Is it safe for confined space entry?
No. A single-gas ammonia meter does not test for oxygen deficiency, combustible gas or other toxic gases, and the listing does not claim a confined-space certification. Use a multi-gas detector designed for entry, and see our confined space detectors page for that category.
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