This was a great concept and for the price of what it promised to do seemed like a good purchase. Tried it for a few minutes then let it charge for a few hours with the wire that was given with the unit. Turned it on and after the initial load screen I get a message "charge battery immediately" which makes no sense. Plug it in and turn it on and the battery indicator says fully charged. Unplug it and it turns off. Try turning it back on same message as before as of the battery is completely drained. Waste of time. Returned.

Las lecturas de PM 2.5, PM 10, PM 1.0, temperatura y humedad no concuerdan con los valores verdaderos. En la calibración manual se puede ajustar la sensibilidad del sensor de PM 2.5 hasta mas menos 33%, pero en el equipo que recibí no fue suficiente. El otro ajuste disponible es básicamente sumar o restar un valor constante y se puede lograr que la lectura concuerde con el valor real, pero al poner una muestra de aire con PM=0 en vez de indicar cero muestra el valor que se sumó o restó. No hay ajuste de sensibilidad para la temperatura y humedad, sólo se puede sumar o restar un valor constante a las lecturas.No tengo medios para verificar si la lectura de concentración de substancias volátiles es exacta.Es posible que se trate de un defecto de fábrica, pero decidí pedir un reembolso en vez de un remplazo

I just did some try outs today. Works perfectly fine, i got kind of concerned from people’s reviews saying the battery sucks or you can’t put out the alarm or change indication of where the alarm should go off. I literally changed those in 1 minute and it’s really easy to go into the menu. The battery life i don’t have any problem with since i use it in specific areas like at work or at home just out of curiousity for a 15 min and i put it off. There’s people complaining about a noise because of the fan. Mine makes zero noise, i’ve put my ear at the device to hear the fan ( because that’s a part of what it uses for measuring the air quality ) and until then i heard the fan. I think this is a good device, if i put it into a smokey area it obviously turns red, if in clean areas like forest it shows green, there’s people that wrote they started comparing with other devices showing different numbers, imho you will always get different numbers that way. I like this one it’s easy to take not too big. I think the only thing i don’t like is that it’s kinda light feeling and the plastic feels cheap, but overall good deal 👌🏼

Firstly, concerning the accuracy, I am uncertain about how it is supposed to function. Each time I power on the machine, it requires calibration, and this process entails leaving the machine outside for a few minutes. If it were a one-time requirement, it would be acceptable, but the initial calibration process takes an unusually long time. The frustrating aspect is that this occurs every time you open the machine. Who has the time to consistently place the machine outside for calibration whenever they wish to check the air quality?Secondly, on their webpage, it is stated that returns are accepted within 30 days. However, when I requested a return on January 1st, it was rejected. After ongoing arguments, they responded on January 7th, claiming that it was already beyond the 30-day return period. Isn't the issue that they consistently rejected my request, prolonging the process until it expired? From the seller's perspective, this is absolutely unreasonable.Moreover, everything is in Chinese, posing a challenge for those who do not understand the language. Additionally, they essentially do not permit returns unless there is a product failure; dissatisfaction with the product is not considered a valid reason for return. Consider this a cautionary note about the product.

There was nothing I disliked about this....Once calibrated, it showed me that I had a big problem with my air quality due to VOCs from an item I had purchased .. I removed the item..I removed the problem...not confused, headache gone, coordination back to normal, asthma clear...if in any doubt as to what you're breathing is safe...GET ONE...I was a novice in these matters...this cleared my mind and also my breathing.. EXCELLENT

I have never bought or used a product like this before, so this review is only relevant to this being my first air quality monitor.Having said that I have no reason to 'disbelieve' the data it's presenting to me.I bought this after being hospitalised due to a rare bacterial infection which, possibly coincidentally, occurred after I had removed some tiles in my bathroom after spotting a leaking toilet seal.For peace of mind, once I had returned home, I thought I'd buy an air quality tester to see the state of the air quality in my flat.I'd already covered the open tile area with pvc sheeting. The air quality in various rooms, including the bathroom area, was of good quality. I placed this monitor inside the pvc sheeting (and re-sealed it) to see what it said about the air there (that had been open prior to my hospitalisation). It came up as 'unsatisfactory' - which may have been the cause of my illness.I would say this gives you peace of mind if you suspect the air in a room is not of acceptable quality, or gives you the evidence to take corrective steps.After replacing the tiles and re-grouting the bathroom that had the missing section, the air quality is reading 'good' again.I would recommend this to give an indication if something may need further investigation.

I purchased a few different models from Amazon and had to send them back because they were so in accurate. This model has a fan which draws air across the sensors making the instrument respond faster to changes in the air. I’m a certified master inspector and use this as part of a preliminary air quality check. I would definitely recommend this product. As with any tool the user needs to understand how to use it and the principles behind what they are measuring.

OK so this device is fantabulous!! OK you MUST calibrate it correctly!! Follow the directions for the first callibration ever - I think that might be 20 minutes outside. Don't ever callibrate it inside. So each time, I set it outside in the clean air and let it do it's countdown in the fresh air. Now, I take it where I want to go and set it in the room for about five minutes. It has helped us SO MANY TIMES!We bought furniture from "The Cannery." It came with quite a smell. I am sensitive to some odors, what was the smell? Was it Mahogany or was it something else? This device told me that the odor was NO PROBLEM at all, so the smell was probably fresh mahogany!!Next, we were kitchen cabinet shopping. Didnt want to spend an arm and a leg. Went to to Kitchen Cabinet store in which the prices are AMAZING. They only sell like five colors of cabinets. The cabinets really looked amazing, even saw that the boxes were made of plywood. The cabinets were shipped in, and then the company would put them together - or you could yourself. We were very close to making an order but before hand, I just had to wonder... Why were they priced so well? I sat out in my car with my device callibrating up through my sunroof on the top of my car in the fresh air. It was time to go in the store... Hiding my device, I went into the store... Only moments later heading over to the cabinet section - "BEEP BEEP BEEP!!!" My device was sounding! Quick, I stuck it in the drawer of the cabinets - it was in the RED!! A little longer and I set it in another cabinet (it doesn't keep beeping) TALK ABOUT TVOC'S!! The formaldahyde was also elevated. OKAY SO YEAH. So just the AIR in that warehouse had elevated TVOC's and formaldahyde, I was concerned for the safety of the workers. They were mostly young and most likely naive to what they were breathing. I did a little research and after speaking with someone knowledgeable on the levels, I learned that the levels in the air shouldn't harm the workers, and that if I bought the cabinets, I'd probably need to air them out or run a fan on them - sound like for weeks or months to help bring those levels down.We've used this multiple times, and let a friend use it... It's fascinating, a great tool to help steer you in what you want to buy.DON'T BE ALARMED and freaked out - understand it's not PPM's - it's a different measurement. Be careful not to freak out and become a "Karen" when something reaches a high number, orange or red color and starts beeping. But, know it's helpful for you to help you make healthier buying deciscions.

Upon my initial observation of the box that this device was shipped in, I was kind of amazed at the quality of the packing and the device itself. I've been using this device for the past couple of days and am fairly impressed with the accuracy and sensitivity of the device. An absolute must for anyone with allergies, or if the household is getting sick for no apparent reason.I highly recommend you follow the directions, especially during the initial unpacking of the device. As recommended, you should leave the device outside in open air for at least 30-60 minutes before turning it on to allow all sensors to vent. Some sensors contain heating elements within it thats necessary for it to function. For best results, let everything air out before applying power.Once I got the device working, I was utilizing it to measure various areas. I took it to work to measure the air quality in one of the datacenter labs and had HCHO of 0.000, TVOC of 0.001, and PM2.5 of 000. The device pretty much provides real time stats because as I was working in the lab, every time I walked by the device, the readings changed very slightly (i.e. TVOC 0.001 increased to 0.005, PM2.5 went from 000 to 002, etc). Numbers all went back to zero after a few moments.This device is so sensitive, as I walked around my home, the measurements showed up in real time. When I walked into the hallway, readings dropped fairly low. Reason is we have a HEPA air filter in the hallway situated near the cat litter.This device is so sensitive, it can tell a difference when I drive down I-280 and I-101 with my windows down. Where I live, I-280 is a freeway completely surrounded by trees, whereas I-101 is mostly industrial. Readings are much lower when driving along I-280. See? Trees are very beneficial to help keeping our air clean!This device is so sensitive, it kinda makes going #2 fun. Because fecal matter releases VOCs due to the sulfurs, and many other chemicals used in your body for digestion, it will register a higher TVOC value on the device. Stinker the poop, higher the TVOC value! You or someone smokes? While smoking, run this device and see how detrimental smoking does to your air quality. Second hand smoke is no joke!Live in California like me? Take this device (rechargeable battery and portable, so convenient!) with you when you go outside to check your air quality due to the many wildfires going on in the state. Although this device will tell you your Air Quality Index (or AQI), it won't be able to do anything more than tell you. Very helpful to allow you to take extra measures to protect yourself (especially if you have asthma, such as myself).Because this device measures the separate AQI values in real time, use this device to check the effectiveness of your air purifier! Bought a new car? Take a reading with this device in your new car's interior. That new car smell, believe it or not, is the emissions of formaldehyde caused by glues and resins curing. Bought new furniture? Use this device to check the HCHO levels that new furniture has the potential of giving off. Most furniture is made of MDF, or particle board. Particle boards are bits of wood bonded by chemicals and glues that emit formaldehyde.What I thought could have made this product cooler:* Ability to save histograms when measurements is started. You have to be on the graphs page and leave it there to get historical graphs. If you leave the page and go back to it, you won't be able to view past measurements.* Ability for the device to save calibration data across power cycles. When you calibrate the device and zero it out, next time you power cycle the device the readings may be a bit different.* Ability to export results over time* Ability to change the user interface color schemaThis product is perfect for taking spot measurements to get a good idea of present environmental conditions. You won't be able to see past readings. I highly recommend getting this product!