The boy started a chronic cough and nasal congestion when he was 3 years old.
This winter, when smog in northern China hit record levels, his symptoms worsened.
Now he needs to clear his sinus every night with salt water through the tube of the machine.
Zhang Zixuan, the boy's mother, says she almost never lets him out, and she usually puts him on a mask when she goes out.
The difference between Britain and China, she says, is "heaven and hell ".
Beijing and other cities are up to 40 times the recommended exposure limit to deadly contaminants that scare parents and lead them to take steps to fundamentally change the nature of their children's urban life.
Parents keep their children at home, even if it means keeping them away from their friends.
The school canceled outdoor activities and field trips.
Parents who have the means are choosing schools according to the air
Some international schools have built huge, futuristic filtration systems.
Look for the dome on the playground to ensure a healthy breath.
"I hope we will move to a foreign country in the future . "
Lawyer Zhang said her sick son, Wu Xiaotian, was playing on the mat in their apartment next to a new air purifier.
"Otherwise we will suffocate.
She is not the only one who wants to leave. Some middle-and upper-
Chinese parents and expats have begun to leave China, and executives say the trend could lead to a huge loss of talent and experience.
On the grounds of pollution, foreign parents have also rejected prestigious jobs or negotiated hard wages for employers.
There is no statistics on the flight, and many are still eager to come to Beijing to work, but discussions about leaving are becoming increasingly urgent around the capital as well as on China's Weibo and parenting forums.
The Chinese are also discussing what they call a "clean holiday"
Aviation destinations in Tibet, Hainan and Fujian.
"I 've been here for six years and I 've never seen a level of anxiety like this," the doctor said . "
Richard Saint Cyr is a new father and family health doctor at Beijing United Family Hospital. half of his patients are Chinese and half are foreigners.
"Even for me, I have never been as anxious as I am now.
The situation is very bad.
He added: "Many mothers, especially the second child.
Guess their life in Beijing.
I think many mothers are tired of leaving their children at home.
"Few developments have eroded trust in the Communist Party as quickly as leaders have failed to control threats to children's health and safety.
In 2008, when more than 5,000 children were killed when the school collapsed during the earthquake, thousands of children were ill and six babies were killed in pollution, causing outrage across the country --Formula scandal
Officials try to suppress angry parents, sometimes by force or money.
But anger at air pollution is more widespread and is just beginning to gain momentum.
"I don't believe in the pollution measures of the Beijing government," she said . "
Zhang's father, Zhang Xiaochuan, is a retired newspaper administrator.
Scientific research proves that long-term fear is reasonable.
Long-term injury to children and the fetus
A study published in the New England Journal of Medicine suggests that children exposed to high levels of air pollution may suffer permanent lung damage.
The study was conducted in more than 1990 cities in Los Angeles, where pollution levels are much lower than in today's Chinese cities.
A study published last month by California researchers showed that children with autism and pregnant women are exposed to traffic --
Researchers at Columbia University found in a study conducted in New York that prenatal exposure to air pollutants could lead to anxiety, depression and concentration in children --span problems.
Some of the same researchers found in an earlier study that children in Chongqing, China, were exposed to high levels of air pollutants in coal before birth.
The laid-off plants had small head circumference at birth, slower growth, and poor performance in cognitive development tests at the age of 2.
The closure of the factory resulted in children with less birth difficulties.
The analysis shows that if China does not change its growth policy and strengthen environmental regulation, there will be no mitigation in the future.
A report released by Deutsche Bank in February said that the current trend in coal use and car emissions means that air pollution is expected to deteriorate by 70% by 2025.
When air pollution soared this winter, some children's hospitals in northern China reported a large number of patients with respiratory diseases.
In a bad week in January, Beijing Children's Hospital treated up to 9,000 patients a day for emergency visits, half of them due to respiratory problems, the state news agency reported.
Parents rushed to buy air purifiers.
The purifiers produced by Swiss IQAir are priced at up to $3,000 and are on display in shiny showrooms.
IQAir China chief executive Mike Murphy said sales in the first three months of 2013 tripled from a year earlier.
Masks are now part of the city's dress code. Ms.
Zhang put six masks on her table and gave a mask with a photo of a teddy bear suitable for the little day.
The school is taking urgent measures.
Private kindergartens in ODA used to take their children on a field trip once a week, but most of them were canceled this year.
In the prestigious Beijing
Four high schools that have long trained Chinese leaders and their children, when the pollution index is high, outdoor physical education classes are now canceled.
"The days of blue sky and seemingly clean air are precious, and I usually go out to exercise," said Dong Yifu, a senior who has just been admitted to Yale University.
Elite schools are investing in infrastructure to keep children active.
Among them are the Beijing Dewei International School and the Beijing International School, which completed two large white synthetic fabric sports domes covering sports fields and tennis courts in January.
Student Activity Director Jeff Johansson said that the construction of the dome and annex buildings began a year ago, providing 1,900 students with a place to exercise in harsh weather and high pollution.
The project cost $5.
7 million, including hospitals-grade air-
The teacher checks the US embassy's hourly air rating to determine if the child should play outside or below the dome.
"Primary school students no longer miss the break between classes," said Mr. Johanson said.
Tara Duffy, an American mother, said she chose a pre-kindergarten school for her daughter, in part because there are air filters in the school's classrooms.
The school, known as 3e International School, also invited doctors to discuss pollution and banned children from playing outdoors during the smog.
She said: "In the past six months, there have been more" red flags "and they have locked the children in . "
Writer and former foundation consultant Duffy. Ms.
Duffy said she also checked the daily air quality index to decide whether to take her daughter to an outdoor picnic or to play indoors.
Now, after nine years here
Duffy, who is leaving China soon, lists pollution and traffic as a major factor.
The calculation is working for expats across Beijing, even foreigners outside China.
An American couple and a young child discussed pollution when considering a prestigious foundation job in Beijing, which is one of the reasons why they rejected the proposal.
James McGregor, a senior consultant at the APCO world Beijing office, said he had heard of an American diplomat with young children refusing to post here.
Despite the fact that the State Council has given Beijing a 15% wage bonus, partly because of pollution.
Other cities in China are also suffering from bad air, with difficulties ranging from 20% to 30% bonuses in addition to 10% of Shanghai.
"I have lived in Beijing for 23 years and my children have grown up here, but if I have young children, I have to leave . "McGregor said.
"A lot of people have begun to withdraw from the plan.