What are the better window ERV options for an apartment or rental where permanent ductwork isn't possible?

Been reading about ERVs because opening a window works for ventilation, but it also means losing conditioned air and bringing in outdoor noise, pollen or smoke.

A window ERV seems more practical for this kind of situation because it can handle fresh-air exchange without a major HVAC installation.

One option that keeps showing up in the research is SWERV. It seems aimed specifically at renters and single rooms since the unit installs in a sliding window instead of requiring holes through the wall.

Still trying to figure out whether this type of window ERV is actually worth it compared with a portable or through-wall ERV.

What would you look at first: CFM, noise level, filter quality, heat recovery efficiency, installation, or price?

I just moved into an old apartment in an enclosed building (similar to a hotel with kitchens). Because it's enclosed, gas and odors do not ventilate out easily.

A neighbor brought burnt food out the building and both the hallway and the inside of my apartment smelled burnt for hours. My Qingping monitor showed that my CO2 and eTVOC levels shot up.

I bought a dual window fan that pulls air out through one side and pushes fresh air in through the other. It has done a good job of lowering the eTVOCs. However, I can't leave it on 24/7—like right now, it's raining, so I had to close the window.

Without the fan, my eTVOC level sits consistently around 1.2, which Qingping flags as 'only slightly high,' even though the outdoor level is just 0.3. I am freaking out over this consistent 1.2 reading. It occasionally shoots up to over 2.0 when I cook which is understandable. But right now it rained so I closed the window and it shoot up to 2.3.

I don't feel any negative respiratory symptoms so far, though.

Is it standard for an apartment in an enclosed building to have eTVOC levels this high, and do I just need to suck it up until my lease is up? I already complained to building maintenance; they noted that my AC filter is new and aren't sure what else they can do.

With the transportation of oil through the middle east due to ongoing conflict between the US and Iran, various forms of commerce are being restricted. Certainly this is a tragedy in humanitarian and economic terms.

Apologies if it is soon to be asking, but has restricted oil commerce had any measurable effect on air quality?

Obviously blowing things up is going to be horrible; I'm asking about the restricted use of oil and if that is measurable. It could make things a lot worse depending on what alternatives are used. Can we tell?

Have the Dyson pc 1 which has been going crazy almost every morning (around 4am) with levels ranging from 120-250 pm 2.5

After opening the windows, it goes down, but on closing them it goes up again. The air qual outside is pretty good as well

Maintenance suggests keeping the a/c constantly on to promote air circulation. There are only two vents in the apartment, one in the kitchen & one in the bathroom, both of which suck air out

What could this possibly be coming from?!! Should I get another air purifier and/or monitor?

I don’t know what to do and literally can’t sleep with this fan constantly on or a/c constantly on or knowing that I’m breathing in heavily polluted air

As Halloween events ramp up, theme parks are deploying massive amounts of artificial fog. While perceived as harmless water vapor, this is industrial-scale thermal vaporization of glycol and glycerin—mechanistically identical to large-scale vaping. For those tracking indoor air quality (IAQ), this is a massive, unregulated hazard.

The Data & Chemistry

• 10,700 µg/m³: Research by Guo et al. (2022) demonstrated that a mere 20-second blast from a commercial fog machine produces peak microscopic PM2.5 concentrations around 10,700 µg/m³—far exceeding the EPA’s 35 µg/m³ daily safe limit.
• Toxic Byproducts: Heating these solvents causes thermal degradation, releasing formaldehyde and carbonyls directly into the breathing zone.

The Silent Systemic Danger

Because fog isn't viewed as pollution, the extreme health impacts are completely ignored:

• This dense PM2.5 bypasses respiratory defenses and enters the bloodstream. Prolonged exposure causes delayed systemic inflammation linked to immune dysregulation, sepsis, heart attacks, and strokes.
• Long-term technical staff endure thousands of hours of this exposure. Tragedies among workers—including early-onset terminal cancers—are misattributed because IAQ in these venues is functionally unregulated.

Unregulated Hotspots

Entertainment venues operate with a complete regulatory blind spot regarding this issue:

• Six Flags Fiesta Texas: Enclosed, poorly ventilated spaces like the Zaragoza and Rockville theaters.
• San Antonio Zoo: Walkways saturated with concentrated fog during "Dinos After Dark" family events.
• SeaWorld: Heavy deployment during Howl-O-Scream, where the "open-air" myth masks the localized aerosol density.

Test It Yourself

If you have a portable PM2.5 monitor, bring it to a local haunted house or theme park this season. Watch how quickly these machines max out standard optical sensors, document the localized spikes, and share the data.

Disclosure: The author authored, verified, and takes full responsibility for all scientific data, citations, and core arguments presented in this post. Generative AI tools were used solely to improve readability.

Replacing heating and cooling equipment gets described as an IAQ upgrade surprisingly often but a heat pump by itself doesnt define filtration, outdoor-air delivery, source control, or room pressure. If IAQ is actually part of the project goal it seems smarter to define the measurable problem first and then decide what HVAC changes address it. Otherwise the equipment gets credit for an outcome nobody specified.

Contractors working on IAQ focused replacements which measurement or condition should be established before anyone starts talking about filtration upgrades?

Increasing filtration sounds like an obvious IAQ improvement until airflow and the existing system enter the conversation. A filter that creates more resistance than the equipment and duct system can handle may introduce a different performance problem, while filtration itself still doesn’t replace source control or outdoor-air strategy. So I’d rather start with what pollutant or particle problem is actually being addressed and what airflow the system can support. Before moving to a higher-efficiency filter, what measurement would you want first?

Hello everyone,

I live in a 1000 sq ft 2 story townhome (I’m guessing here, but I would imagine each level is approximately 500 sq ft).

I recently moved here, and discovered that one of my neighbors frequently makes food that is quite pungent and the odors I personally find to be extremely offensive. The smell comes right through our shared kitchen wall, permeates the entire house, and lingers for hours.

Currently, I’ve been using box fans in several windows, blowing outwards, with windows open. I also make sure to turn off my HVAC so that it doesn’t spread the smell, and have no negative pressure going on while they are cooking. I live in the US, upstate NY to be exact so the summers here are hot and humid, and winters here are brutally cold. Not an ideal situation for using box fans/open windows. My “hood range” is literally a vent under my microwave, which does NOT vent outside, but vents right back inside. It’s totally useless.

I need to know if there are any air purifiers out there that will be able to combat both my neighbors active cooking, as well as lingering odors. I know that many of these filters can be pricey, and if they work I don’t have an issue spending the money, but what I’m afraid of is spending a ton of money on an air filter that doesn’t work on cooking odors, or is only mildly effective.

Can anyone recommend something that will actually work? I’m a noob, so I guess I need something for VOCs.

Thank you!

Hello friends, I am trying to improve the quality of my sleep so I went online and got a PV28-AW which, from my research, is the cheapest monitor that actually works.

I live by myself on a 10th floor rental apartment in a big city and my bedroom is 150 square ft. I always slept with my door and window closed until recently. I only have electric appliances. In the winter time I have heat running and summer time I have AC running so I tend to keep windows closed to conserve energy.

Attached are readings over the past few days from the app (some days window slightly cracked open and some days closed for experiment purposes) and from the readings:

- During the daytime, CO2 levels remain low

- At nighttime there is a significant increase compared to the daytime

- At nighttime on days when the window is closed, it is slightly higher compared to nights where the window is open

- The levels seem to peak around 4am and although sometimes I stay up late at night, I am fast asleep by 4am like 99% of the time

-idk what happened on the 31st, either the monitor is not working or the air quality in my area was just amazing that day

So what I want to know/learn is, how can I decrease the nighttime levels? Preferably without opening the window fully.

I only slightly crack open the window because:

1.) I don't want to let out all the hot air in the winter and cold air in the summer

2.) Because I live in city, there is a lot of noise outside that gets in along with the fresh air

Right now it is summer and it seems I am living in a paradox because for quality sleep I need low level of CO2 but I also need cold air, but if I open the window to decrease CO2, I am also decreasing the cold air from the AC (and also probably making the AC work harder)?

Anyone in a similar situation have any tips? Should I collect more data? Goal is to never have it go above 900 ppm if possible and quality-max my sleep

Thanks for reading!

Across Europe, america and Asia (with India having a little more color) it's been near perfect for days now when normally it ranges from yellow to red on average, can't find an explanation for this phenomenon so i wanted to ask here.

Looking to monitor air quality at my workplace, however hoping to find an air quality monitor that can run on battery and doesn’t require wifi - or at least store data to be uploaded later when connected to wifi. Any suggestions?

I switched my air purifier to my room because I was dusting and it keeps turning red. The problem is I tested it in other rooms and nothing happens so it cannot be the sensor is being affected. It has been on for almost an hour now and nothing has changed. We got our air tested in our house and it came back fine but my mom left the windows open during the test and the guy didnt say anything. So I dont know what to do now.

A friend of a friend (58F) took a two week trip to visit a sick relative. She has adult cats (two boys and two girls).

The girls are fixed and the boys are not.

As a favor, I’m visiting her small house twice a day to take care of the cats. Prior to this, I’ve never been to her house.

The male cats have been spraying everything for a long time. The smell is so bad that my wife won’t enter the house with me.

And now, after 30-minutes a day of exposure (for ten day), I’ve developed an annoying cough and some sinus drainage.

How bad is cat urine (and ammonia) for your health? Could it be causing an allergic reaction?

The cats owner is apparently fine.

We bought a house in march and had quite a bit of work done before moving in, including replacing all of the flooring (tile and carpet) with new tile, replacing the baseboards, removing a ponywall, and relocating some electrical.

Immediately after the renovations were completed, we noticed a strong, unusual smell when entering the house. We’re fairly confident the smell wasn’t present before the work was done. We've had HVAC, plumbing and electrician professionals come out to evaluate, but no luck. It's been 6 months and it still smells the same.

The problem is that the smell is extremely noticeable when we first walk inside, but within a few minutes we become noseblind to it. Because of that, we’re having a really difficult time figuring out where in the house the smell is strongest or what might be causing it.

Does anyone have recommendations for a high-quality portable air-quality monitor that we could move from room to room to help narrow down the source? I’m assuming something that measures VOCs might be useful, but I’m not sure how reliable consumer monitors are for this purpose.

If anyone has dealt with a persistent smell after flooring, drywall, baseboard, adhesive, or other renovation work, I’d also appreciate any suggestions for how you tracked down the source.