What AQI Is Safe to Walk My Dog? The Band Table a Vet School Published, and the Number Nobody Publishes

No agency or veterinary group publishes a safe AQI number or a number of outdoor minutes for dogs. What exists is guidance written as actions. EPA tells owners to use the human Air Quality Index for their pets the way they would use it on themselves, and Colorado State University’s veterinary college published band-by-band actions for dogs in July 2026. CSU’s chart has owners shorten and slow walks above AQI 100 and limit unusually sensitive dogs sooner, from AQI 51. Ask your veterinarian where your own dog’s line sits.

The wildfire smoke playbook for pets covers the rest of the hazard: signs of exposure, ash, the evacuation trigger, and what to do when the fire itself gets close. This page does one narrow thing: it sets out the published bands and instructions on air quality and animals in one place, attributed, and says plainly which cells are empty.

What EPA and Colorado State Published

EPA maps the human number onto your animal by analogy. Its Wildfire Smoke Guide fact sheet, “Protect Your Pets From Wildfire Smoke” (EPA-452/F-26-007), says: “Reduce your pet’s exposure to smoke as you would reduce your own by using the Air Quality Index at the Fire and Smoke Map to inform decisions.” EPA does not publish an animal AQI. It tells you to use the human one, at a named source, the way you would use it on yourself.

One veterinary institution has published band-level actions for dogs. Colorado State University’s College of Veterinary Medicine and Biomedical Sciences published “How poor air quality can impact dogs” on July 21, 2026, with a chart of recommendations by AQI band. CSU describes it as an adaptation of the Air Quality Index by its own doctors. It is not an EPA product, an AVMA policy or a regulatory standard, and it is the closest thing to a published answer that exists.

The Dog Table CSU Published

The right-hand column below paraphrases CSU’s July 21, 2026 page.

AQI band (CSU’s headings)	What CSU published for that band
Green (0 to 50)	No changes needed.
Yellow (51 to 100)	Most dogs continue as normal; watch for coughing or breathing changes. Unusually sensitive dogs should have outdoor exercise limited.
Orange (101 to 150)	All dogs get shorter, lower-intensity outdoor time: walks instead of runs, and outings during better-air windows. Sensitive and unusually sensitive dogs are limited to bathroom breaks. Manage indoor air: close windows, run AC on recirculate, use a HEPA purifier if available.
Red (151 to 200)	Limit outdoor time and restrict exercise to low intensity (walks, not running or intense play). Monitor the AQI and go out when it improves. Optimize indoor air: close windows and doors, use an HVAC system with an up-to-date filter, run AC on recirculate, add a portable HEPA purifier or a DIY box fan and filter setup, remove candles, incense, diffusers and aerosols, and keep surfaces dust free. Monitor sensitive and unusually sensitive dogs closely.
Purple / maroon (201 and above)	Keep dogs indoors as much as possible and go out when the AQI improves. Optimize indoor air, and consider relocating sensitive or unusually sensitive dogs to cleaner air if indoor air quality cannot be maintained. Watch for changes in behavior or symptoms and contact a veterinarian if anything abnormal appears.

Source: Colorado State University Veterinary Health System, “How poor air quality can impact dogs”, July 21, 2026. The band numbers are EPA’s AQI categories, which CSU adopted unchanged.

The chart’s DIY box fan carries a safety condition that CSU does not state, but EPA does. EPA’s cleaner air room fact sheet (EPA-452/F-26-005) says to use a newer box fan (made since 2012) with a UL or ETL logo, because those fans have thermal safety fuses that reduce the risk of fires or burns. It also says: “If you must use an older fan, never leave the fan running unattended while you are away or sleeping.”

Three points about the table.

It is written in verbs, not durations. Shorten, limit, restrict, monitor. Not one cell says how long, and the other sources on this page are written the same way.

It escalates a band earlier than the human categories do. For an at-risk dog, caution starts in the 51 to 100 row. AirNow describes that band for people as acceptable air, and it is where CSU tells owners of unusually sensitive dogs to start limiting exercise.

It ends in a phone call. CSU’s top band closes with contacting a veterinarian if anything abnormal appears, which is where every other source on this page also lands.

CSU’s Two Sensitivity Categories

Most of the table’s instructions apply to a category rather than to all dogs. Per CSU’s July 21, 2026 page:

• Unusually sensitive: brachycephalic (short-nosed) breeds such as bulldogs and pugs; puppies; geriatric dogs; pregnant dogs; dogs with a known heart, lung or airway condition; dogs with advanced metastatic cancer; and dogs on chemotherapy or immune-suppressing medications.
• Sensitive: all of those dogs, plus dogs that are overweight or obese; senior dogs; dogs with mild or intermittent heart, lung or eye conditions; dogs with allergies; dogs with an endocrine disorder such as diabetes or hypothyroidism; breeding male dogs; and dogs with an immune-mediated disease.

The lists are broad. Between allergies, overweight, senior age and endocrine disease, many household dogs sit in one category, so the more conservative column applies to more readers than expect it. CSU attaches no number to either category: no multiplier, no percentage reduction, no separate breakpoint for a pug. The categories change which instruction applies, not by how much. No source cited here publishes a numeric adjustment for a flat-faced or senior dog.

No Source Publishes Minutes per AQI Band

No agency, veterinary association or veterinary college cited on this page publishes a number of allowed outdoor minutes per AQI band, for a dog or any other animal. The guidance is written as actions and conditions:

• AVMA’s “Wildfire smoke and animals” page says: “Let dogs and cats outside only for brief bathroom breaks if air quality alerts are in effect.” It does not define brief. It also says to avoid intense outdoor exercise during poor air quality and to exercise pets when dust and smoke have settled, which is a condition, not a clock.
• Cornell’s Riney Canine Health Center (page last updated December 23, 2025) says the best protection is staying indoors with windows and doors closed and “limiting outdoor time to only bathroom breaks.” It advises avoiding running or hiking until air quality improves and considering indoor air purifiers or filters.
• EPA’s pet fact sheet says to keep pets indoors as much as you can, with doors and windows closed if you can stay cool, and to keep outdoor bathroom breaks short. It also says to bring outdoor pets into a less smoky, cooler place such as a utility room, garage or bathroom, and to move potentially dangerous products, such as pesticides, out of their reach. The conditional matters: closing windows is tied to being able to keep the animal cool.

Minute figures for AQI bands circulate online, but none of these sources publishes one, so this page does not offer one. What replaces it is reading the number correctly and getting a duration from your veterinarian.

The Index Was Written About People

AirNow’s AQI Basics page defines six categories. They are human health categories, and they mention animals nowhere.

AQI category	Values	AirNow’s description for people
Good	0 to 50	Air quality is satisfactory and pollution poses little or no risk.
Moderate	51 to 100	Air quality is acceptable, but there may be a risk for some people, particularly those unusually sensitive to air pollution.
Unhealthy for Sensitive Groups	101 to 150	Members of sensitive groups may experience health effects; the general public is less likely to be affected.
Unhealthy	151 to 200	Some members of the general public may experience health effects; sensitive groups may experience more serious effects.
Very Unhealthy	201 to 300	A health alert: the risk of health effects is increased for everyone.
Hazardous	301 and higher	A health warning of emergency conditions: everyone is more likely to be affected.

Source: AirNow.gov, “Air Quality Index (AQI) Basics”.

Two consequences follow, and they run in opposite directions.

The sensitive groups are human sensitive groups. EPA’s Technical Assistance Document for the AQI (EPA-403/B-26-003, May 2026) names them for particle pollution as people with heart or lung disease, older adults, and children including teenagers. It adds that during a smoke event EPA recommends including pregnant people as an at-risk group. EPA’s pet fact sheet names pregnant animals in its own at-risk list, and CSU’s unusually sensitive category names pregnant dogs. Still, no animal appears in the AQI’s definition of a sensitive group. That is why CSU had to write a separate list.

The index does not include heat. The same document says: “The AQI does not apply to hazardous air pollutants, extreme heat, and other aspects of outdoor air.” A green reading on a very hot afternoon says nothing about heat risk. Heat is a separate hazard. Our heat and hot-car page covers it, and the cooling gear comparison for flat-faced breeds covers equipment for the breeds EPA singles out for extra caution in smoke or heat.

Effort Matters More Than Minutes

Published guidance rarely restricts being outdoors. It restricts effort. EPA’s pet fact sheet says to spend less time outdoors and limit physical activity when it is smoky, noting that it is not a good time to go for a run with your pet, and that cutting activity matters most when it is also hot. CSU’s orange band says shorter, lower intensity, walks instead of runs. Its red band restricts exercise to low intensity. Cornell says to avoid running or hiking.

AVMA’s livestock guidance states the mechanism: do not require animals to perform activities that substantively increase airflow into and out of the lungs. Our reading of that sentence: the smoke an animal breathes in depends on how hard it is breathing, not only on how long it is outside. So the doorway question is not only how many minutes. It is whether the outing is a sniffing walk on a leash or a run at the park.

A high-drive dog still needs somewhere for its energy to go. Cornell notes that indoor enrichment such as long-lasting treats or puzzle feeders may help prevent boredom or unwanted behaviors, and our snuffle mat, slow feeder and lick mat comparison covers which tool suits which dog.

Smoke Plus Heat

EPA’s pet fact sheet says evidence in humans indicates that smoke and heat together are much worse than smoke alone, then adds: “This is also likely true for your pets.” The word likely is EPA’s. The human evidence is described as evidence and the extension to pets as likely, so do not upgrade it.

The next EPA sentence matters most for a specific animal: older, younger or pregnant animals, and animals with heart or lung disease, are especially at risk from smoke or heat and should be closely watched during all periods of poor air quality. AVMA agrees that animals with cardiovascular or respiratory disease should be watched closely whenever air quality is poor. Neither ties that caution to a threshold. For a dog or cat with existing heart or lung disease, no band is described as clear.

Reading the Number Correctly

Two apps can show two different numbers for the same afternoon and both can be right. Settle three questions first.

1. Is it a forecast or a reading right now? AirNow reports both. The current value is the NowCast AQI, which EPA’s technical document describes as the latest information on air quality where you are. It changes during the day. EPA also notes that even on days when the daily forecast is not good, there may be times when air quality is fine for outdoor activity. A bad forecast is not a closed day, which is the same idea as CSU’s advice to monitor the AQI and go out when it improves.

2. Is it a regulatory monitor or a low-cost sensor? The AirNow Fire and Smoke Map, run by EPA with the U.S. Forest Service, shows both permanent and temporary monitors run by air quality agencies and sensors, most owned and operated by the public. EPA says: “EPA does not use air sensor data for regulatory purposes.” Its Q&A lists the limits of sensors: they may occasionally report questionable data, they have a bias (regularly reporting higher or lower than the actual air), and most are not run by air monitoring experts. EPA also says that despite these limitations, sensors are valuable for general information, and that EPA and the Forest Service apply quality control steps and a correction equation before showing sensor data. Use the reading, and know which kind it is when you write it down.

3. Which pollutant is the number about? The AQI covers five major regulated pollutants and is the highest value calculated for any of them. The Fire and Smoke Map shows only fine particle pollution (PM2.5), the main pollutant in wildfire smoke. EPA’s Q&A says it does not show other types of pollution, including ozone (smog). So a high AQI driven by ozone will not appear on the map EPA’s pet fact sheet points to, and an ozone day is not a smoke day. This page covers particles. Our ozone action days and pets page covers what EPA publishes about ozone timing and where it differs from the smoke advice.

A reading shows conditions at one monitor or sensor at the moment you view it. Your air is likelier to match it when concentrations are stable, winds are light and no pollution sources lie between. It is likelier to differ when concentrations change frequently, smoke plumes are in the area, sources are nearby, or terrain such as mountains, hills and valleys intervenes. EPA says you may see differences even between two sensors that are near each other.

The Trend Line

EPA’s Fire and Smoke Map Q&A says the dashboard for a monitor or sensor shows how particle pollution has changed in the last 30 minutes, and: “You can use that information to guide short-term activities, such as opening or closing windows, or going outside to walk the dog.” That is the only place in the federal documents cited here that names walking the dog. It hands you a direction of travel, not a threshold. A reading that has fallen for half an hour as a plume clears and the identical reading climbing hard as a new plume arrives are the same number and two different decisions.

What the Bands Are Made Of

Each AQI category corresponds to a concentration range for each pollutant. For fine particles, EPA’s Technical Assistance Document for the AQI (EPA-403/B-26-003, May 2026) publishes these 24-hour PM2.5 breakpoints:

PM2.5, 24-hour, micrograms per cubic meter	AQI	Category
0.0 to 9.0	0 to 50	Good
9.1 to 35.4	51 to 100	Moderate
35.5 to 55.4	101 to 150	Unhealthy for Sensitive Groups
55.5 to 125.4	151 to 200	Unhealthy
125.5 to 225.4	201 to 300	Very Unhealthy
225.5 and above	301 and above	Hazardous

Source: Table 6, “Breakpoints for the AQI”, in EPA-403/B-26-003.

The top of the Good band is 9.0 because EPA revised the particulate matter standards in a rule published March 6, 2024 (89 FR 16202), effective May 6, 2024. Older reference material may still show the previous ceiling.

The bands are concentration cut points derived from the human health standard. EPA’s document says an AQI value of 100 generally corresponds to a concentration equal to the level of the short-term national standard for protection of public health. Nothing in that derivation involved a dog. The bands describe the air well. They do not describe the animal breathing it, and every layer between the two, CSU’s included, is an adaptation with a name attached.

When It Stays Bad for Days

Multi-day smoke changes the problem from timing an outing to managing a house, and this is where the human safety limit matters most.

EPA’s pet fact sheet adds the indoor-source side: avoid cooking, especially frying or broiling, and do not vacuum, burn candles, use a fireplace or woodstove, or smoke or vape, because these add particles to your home. For homes without air conditioning, it suggests closing blinds and shades before it gets hot, opening windows and using fans at night when it is cooler to exhaust hot air or draw in cooler air, then closing the windows and using a portable air cleaner to remove smoke.

EPA’s “How to Create a Cleaner Air Room at Home” fact sheet (EPA-452/F-26-005) has a clause that must not be trimmed: “Prevent smoke from entering the room. Close windows and doors, but do not do anything that makes it hard to leave the room in an emergency.” It also says to stay cool by running fans, window air conditioners or central air, and, if your air conditioner has a fresh air option, to turn it off or close the intake and run it in recirculation mode.

The same fact sheet says a cleaner air room may not be the best option if you cannot stay cool at home, the power goes out, or too much smoke is still getting in after you have followed the steps above. It suggests staying with friends or family, going to a public cleaner air shelter, or finding another location with air conditioning and good air filtration. EPA’s AQI technical document carries the heat warning too: “If you don’t have an air conditioner, staying indoors with the windows closed may be dangerous in extremely hot weather.” It adds that if you are hot, you should go somewhere with air conditioning or check with your local government about cooling centers.

The cost is real. Following that advice can mean leaving a house where your animals are, or moving them somewhere that may not take them. Neither EPA passage is written about animals, and neither says whether a public cleaner air shelter or cooling center admits animals, so do not assume it does. Confirm by phone before you need it. Our pet emergency playbooks hub can help you build that call list. What you should not do is seal a house you cannot cool: EPA’s warning about closed windows in extremely hot weather applies to the people in it too.

On filtration, EPA’s “Indoor Air Filtration” fact sheet (EPA-452/F-26-006) says portable and DIY air cleaners deliver cleaner air to a single room, HVAC filters can serve the whole home, and two or more well-placed portable or DIY cleaners can be as effective as running a central system continuously with a high-efficiency filter, at possibly lower cost. It says electronic air cleaners are not recommended for smoke removal because they may not remove smoke particles effectively and may produce ozone, and points to California Air Resources Board certified cleaners because they produce little or no ozone. Buy against EPA’s criteria and the manufacturer’s room-size rating, not against a claim about pets.

Other Animals in the Household

Cats. No source cited here publishes an AQI band table for cats. AVMA covers cats alongside dogs in its brief-bathroom-breaks instruction above. EPA’s pet fact sheet lists signs to watch for in any animal and adds that cats may act restless, search for a cool spot, pant, drool and have sweaty paws. Excessive panting is on EPA’s list of signs to consult a veterinarian about.

Birds. This is the one place two sources come close to an absolute, and neither attaches a number. AVMA says birds “are particularly susceptible and should not be allowed outside when smoke or particulate matter are present.” EPA says pet birds are particularly susceptible and should be kept inside, in a cleaner air room if possible, when smoke is present. The trigger is smoke, not an index value. Our bird and parrot emergency preparedness guide covers enclosures and transport.

Horses and livestock. EPA’s “Protect Your Large Animals and Livestock From Wildfire Smoke” fact sheet (EPA-452/F-26-008) uses the same analogy as the pet sheet: reduce exposure to smoke and heat the way you reduce your own, with less time in smoky air, more time in cooler or shady areas, plenty of water, and limited physical activity. It says to avoid riding, training or forced walks for horses, and to avoid running cattle through chutes. It gives livestock four to six weeks to recover fully before strenuous activity, and AVMA gives the same interval counted from when air quality returns to normal, and says handling, moving or transporting livestock in that window may delay healing. Our horse and livestock evacuation basics covers transport. That recovery window is published for livestock only. Neither source publishes one for dogs or cats, and you should not assume one.

Water, for every species. EPA’s pet fact sheet says: “Make water available at all times.”

What About Something Over the Dog’s Face?

Cornell’s canine health center notes that people can wear masks outdoors while pets cannot, which may put pets at greater risk. EPA’s pet fact sheet and AVMA’s pet page do not mention pet masks. EPA’s human-facing “Prepare for Wildfire Smoke” fact sheet (EPA-452/F-26-001) tells people to use NIOSH Approved N95 respirators and not to rely on dust masks or bandanas. Our review of dog smoke masks works through the manufacturer claims and the seal problem. No filtration figure for a pet product appears in the federal or veterinary material cited here, so nothing supports relaxing a band because a dog is wearing one.

Ask Your Veterinarian for the Duration

Everything on this page converges on the same handoff. EPA says pet owners should consult their veterinarian to manage pets during a smoke event or a combined smoke and heat event, and to make an evacuation plan. AVMA says to consult your veterinarian if any animal shows signs of smoke exposure. Cornell says to contact your veterinarian with concerns about exposure risk or symptoms. CSU’s top band says the same.

Owners do not always start there. A study in the Journal of the American Veterinary Medical Association (Scott and colleagues, February 2026) surveyed 836 dog owners in the western United States. Few actively monitored air quality: less than one-fifth reported knowing the AQI well, and only one-quarter said they check it frequently. Essentially all (99%) relied on veterinary professionals for pet health information, and 91% considered them the most trustworthy source.

Use one appointment you already have, before smoke season rather than during it, and ask:

• Which of CSU’s two categories does this animal fall into, sensitive or unusually sensitive, and why?
• Given its airway, heart and lungs, at what point on the AQI scale do you want outdoor time cut to bathroom breaks?
• Is there a duration you want me to hold to at that point, and does it change if it is also hot?
• What symptom means call you, and what symptom means come in now?
• If we relocate for cleaner air, what should travel with this animal, and what medication supply should I carry?

Write the answers on the same card as the clinic’s after-hours number. That card is the only version of the threshold that is really about your animal.

The Doorway Checklist

• Check a reading before the leash comes off the hook. EPA’s instruction is to use the AQI at the Fire and Smoke Map to inform decisions.
• Note which source the number came from: a regulatory monitor, a corrected low-cost sensor, or a daily forecast.
• Look at the trend, not just the value. The map dashboard shows the last 30 minutes.
• Check the temperature separately. The AQI does not apply to extreme heat.
• Decide the intensity, not only the length. A sniffing walk on a leash is a different exposure from a run.
• Know which of CSU’s categories your dog is in before you are standing in the doorway.
• Keep birds inside when smoke is present.
• If it will be days, move to the indoor plan: cleaner air room, filtration, and no indoor particle sources. Stop at the human limit: a house you cannot cool is a hazard to the people in it.
• Confirm by phone whether any cooling center or cleaner air shelter you might use admits animals.
• Watch for the signs EPA lists and call your veterinarian rather than waiting: excessive coughing or gagging, trouble breathing, red or watery eyes, nasal discharge, inflammation of the throat or mouth, reluctance to eat hard foods, excessive panting, fatigue or weakness, disorientation, uneven gait, stumbling, reduced appetite or thirst.

Where to Go Next

This page is the threshold spoke of our pet emergency playbooks hub.

• When the fire itself is the problem: the wildfire hazard playbook for pets covers the evacuation trigger and recovery, and the ash and hot-debris paw protection guide covers the ground your dog walks on after the smoke clears.
• When the answer is stay in: the indoor mental-work gear comparison and the review of dog smoke masks.
• When smoke and heat arrive together: the heat and hot-car page, the cooling gear comparison for flat-faced breeds, and the wildfire alert app comparison for pet owners.
• When the alert is not about smoke: ozone does not appear on the Fire and Smoke Map, and EPA’s timing advice for it points at the morning. Our ozone action days and pets page carries that material.

Then ask your veterinarian, at your next appointment, where your animal’s line sits. No source publishes that number.