NEW YORK (CBSNewYork) — As the weather gets colder, restaurant owners are winterizing outdoor dining spaces, but it’s causing concern that they are becoming too enclosed and exposing diners to COVID . On the Upper East Side, Alexandra Boet searched for open and breezy outdoor dining. “I’m sure there’s more ventilation than if you’re inside,” she said. But colder weather brings walls, plywood roofs and tents to outdoor structures. They can reduce fresh air. “Ventilation is critical,” said Dr. Len Horovitz, an internist and pulmonologist at Lenox Hill Hospital. CORONAVIRUS PANDEMIC Health Experts Stress Need To Fight ‘Mask Exhaustion’ Tri-State Area Coronavirus Travel Advisory List CBS2’s Dr. Max Answers Your Health Questions Resources: Unemployment, Hunger, Mental Health & More Remote Learning Tools For Parents Teaching At Home Complete Coronavirus Coverage Horovitz says he worries winterizing threatens to wreck what started out as a good thing. “Outdoor dining was really great over the summer when everything was unenclosed,” he told CBS2’s Dave Carlin. Horovitz says he considers tents and igloos problematic because they may not have proper ventilation. (credit: CBS2) “The problem is when walls are created, when they want to heat the inside and when there may not be sufficient ventilation inside to ensure lack of contamination,” he said. He wants restaurant owners to keep air circulating with open spaces and tells the public to choose outdoor dining areas carefully. “Ideally, you’re at a table outside in something like a parking lot with nothing overhead, and you take your football blanket and put it around you if that keeps you warm enough,” Horovitz said. Remember, heaters do not circulate air, and if the space is noisy, that can be a big problem. “Loud background noise and background music in restaurants makes people talk louder or shout,” Horovitz said. “You’d project farther and that will project your aerosol farther, so yes, that’s a danger.” CORONAVIRUS: NY Health Dept. | NY Call 1-(888)-364-3065 | NYC Health Dept. | NYC Call 311, Text COVID to 692692 | NJ COVID-19 Info Hub | NJ Call 1-(800)-222-1222 or 211, Text NJCOVID to 898211 | CT Health Dept. | CT Call 211 | Centers for Disease Control and Prevention As coronavirus cases surge again, unless you can find properly disinfected open outdoor set-ups, the doctor recommends takeout. “Just pick up the food and take it home,” Horovitz said. To dine with more peace of mind. MORE FROM CBS NEW YORK De Blasio Says NYC Parents Should Be Ready ‘As Early As Monday’ For All-Remote Learning Bicycle Thefts Surging In New York City As Pandemic Causes Nationwide Shortage Of Bikes 2 Killed In Explosion At Veterans Affairs Hospital In West Haven, Conn. You can get the latest news, sports and weather on our brand new CBS New York app. Download here .