What can Delhiites do to reduce the city's horrific levels of air pollution?

Start with the smaller things. Plant a tree and take care of it. Stop using petrol/diesel vehicles whenever you can. Opt for public transports/car pools or even CNG is better. Make sure your vehicle is always under pollution control measurements.

What You Can do to reduce air pollution: *Encourage your family to walk to the neighbourhood market by walk. * Use public transport more ( metro etc.) * Reduce use of aerosols .( Deodrants etc.) * Plant a tree around your locality with friends. * Reduce the Use of Air Conditioners. These maybe some ways you can give your part towards this noble cause. Be The Change. Cheers.

In order to eliminate a problem or find a logical workable solution to a problem, first we need to deeply know/understand the major cause/root cause & some facts regarding it.In 2014, WHO declared New Delhi as the "most polluted city" in the world. Not just complex, but this is a very critical threat to the lives of 10 million residents of Delhi-NCR. As many as 10,000 people a year may die prematurely in Delhi as a result of air pollution - wikipedia. Knowing this point alone gives us an idea about how critical the present situation of residents of Delhi is.Major factors contributing to the air pollution in Delhi :• Particulate Matter : 80%• Other : 20%Note : These are estimated amounts, could be more or less by 1-2%.              Lets jump to the top cause - "Particulate Matter". What is it & how does it affect our health. Atmospheric particulate matter or simply particulate matter (PM) is "microscopic" solid or liquid particles suspended in air (aerosol). PM is the deadliest form of air pollution due to their ability to penetrate deep into lungs & blood stream of our body causing permanent DNA mutations, heart attacks lung cancer & premature deaths -wikipedia. Considering this, asthama & other less fatal chronic respiratory disease are just a common thing for the majority of residents in Delhi. Sources of PM in Delhi :• Road Dust (dust from soil erosion, deforestation & uncovered construction of buildings) : 50% • Industries (Industrial wate) : 23% • Vehicles (exhaust emission) : 7%PM also affects flora adversly by blocking the pores of green plants & hence their ability to produce Oxygen & their own food by photosynthesis is reduced to critical levels. The flora dies, becomes dysfunctional, or less functional eventually, depending on the amount of exposure to PM.Now lets jump to the Other (20%) factors :     • Crop residue burning in & around NCR accounts for 75% other pollution, while remaining 25% of other pollution is caused by household activities of the residents. Thinking about it, its natural & can't be avoided. But the crop residue burning can & should be avoided to decrease this other (20%) pollution to 6%.So, these were the facts we needed to understand the reason "how". Now the basic question comes - "why". The reason is quite obvious - OVERPOPULATION. Overpopulation leads to overuse of industrial resources & further resultant issues/problems that we've already discussed above.Solution(s) :• Population control : Reducing population influx into Delhi from other states. Efficiently implementing 1-child policy. And most importantly - Creating same or even better opportunities & facilities in other states/cities as well so majority of people don't have to rush into the Capital. Simply, India need more & more planned cities. Chandigarh is a fine example of that.• Relocation of Industries : Just shift at least 70% of the existing industries to the less populated open areas. Its not easy to implement but we should think about innovations & inventions in order to eliminate the need to some Industries & their products.• Heavy & extensive plantation of flora : Leave no land bare. Either it should be brick or grass. Cover the land totally so there will be no circulation of dust into air during storms & winds. Removal of the extra dust from everywhere, every inch & dump it into river Yamuna, easy-peasy.• Vehicular enission only accounts for 7% of particulate matter & air pollution. I don't think there is a need to stress out our brains on this.Nonetheless, such solutions should be implemented by the governments honestly & effectively. And thats not gonna happen very soon, cuz India critically lack such governments & people who can implement things in real other than fighting each other like cheapsticks for votes & shit.So, lets just jump to the Prevention :)• Surgical Masks : No matter what the idiots think or how people stare at you - Always keep your nostrills covered with a surgical mask while travelling or hanging out in open. It is "The Necessary" thing on the list. Don't wanna do it? Then you could be wearing an oxygen mask instead of surgical mask in a hospital fighting with lung cancer or a heart attack.• Indoor Therapy : Forget jogging/walking in fresh morning breeze of toxic air. Forget that Yoga you're peacefully doing in so called fresh air of your balcony. Your lungs works with twice the normal efficacy while exercising so thats how more & more PM will penetrate your lungs in a very short time. So, better just hold your horses & emotions & stay inside & workout on a treadmill, it'll burn more calories & you don't have to inhale that toxic air. Of course you can't stop travelling to & from from your woekplace to your home but still, try to stay indoors as much as you can. Air conditioned air filters some amount of PM & its a better air for your health.• A healthy routine : You can't do much but you can still control what you eat to stay healthy. Drink lots of water & comsume all those foods that are better for your overall health. Just google it up, my fingers are now tired of writing :DMaybe I've missed some points. If I ever come across anything good that can prolong one's health in Delhi, I'll surely update this answer. Till then Take Care!Take a deep breath, oh sorry, take a stretch & get back to work!

# What the doctor ordered:* Avoid travelling during peak traffic hours* Avoid using insect and mosquito repellents* Switch off the car ignition when it’s not in use (even at traffic signals)* Don’t burn waste, leaves, paper and plastic* Use masks whenever there is excessive dust in the air* Close windows if construction work is underway nearby* Participate in awareness programmes on air pollution* Undergo lung function tests on a regular basis~Medical advice from Dr Sanjeev Mehta, pulmonologist (chest specialist), Lilavati Hospital in Bandra--> Ways to reduce air pollution# At home* Turn off electrical and electronic appliances when they are not in use. Also, recycle paper, plastic, glass bottles, cardboard and aluminium cans. This helps conserve energy and reduce emission from coal-based power plants* Plant trees, as they improve the air quality. Trees provide shade and filter, absorb and block pollutants* Use solar lighting, or connect your outdoor lights to a timer*Test your home for high levels of radon, a dangerous radioactive gas that is odourless and tasteless* Do not smoke indoors# Buy smart:* Buy energy efficient appliances* Choose efficient, low-polluting models of vehicles* Choose products with less packaging, or packaging that is reusable* Shop with a cloth bag instead of taking paper and plastic bags from shopkeepers* Buy rechargeable batteries for devices that are used frequently# Drive wise:* While travelling long distances, plan your trips so as to save fuel* Keep tyres fully inflated and aligned* During summers, fill up the fuel tank during cooler evening hours, to cut down on evaporation. Avoid spilling petrol or diesel* When possible, use public transport, walk, or ride a cycle* Regularly tune the car engine and carry out maintenance checks* Report smoking vehicles in your vicinity* Join a car pool or van pool to get to workAdapted From : http://www.hindustantimes.com/mumbai/pollution-check-for-mumbai-what-you-can-do-to-clear-the-air-around-you/story-yMHaYFrW3qPpPK8Fmw6zIM.html

As you said the level of air pollution in Delhi is horrific  . Therfore I won't agree on the solutions given by other friends . Switching of car engine on signals and controlled use of mosquito repellants will not help the people of Delhi as it is very late to adopt these measures. The people of Delhi haven't really deciphered the problems they have created for themselves. Before it becomes too late for even the state to Interfere, the centre and the state governments must bring in legislations to do so.Odd even scheme is one of those ideas. Compulsory car pooling should be introduced in the city in phased manner.  At least each car should have three passengers else people should be forced to use Public transport or Battery operated bikes .Metro , and CNG busses should be able to cover almost the entire region so that the dependence on private vehicle reduces.As a long term measure hybrid and non polluting   fuel engines  should be encouraged. Government should work together with the private sector to come up with successful models of electric bike and cars.Strict actions should be taken against the defaulters. In January 2016, an idea was put forward to  operate a luxury bus in Delhi .This bus would have the best of the facilities and ticket reservations would be done online. This bus will cater to upper middle class and upper class people who are uncomfortable with the other public transport such as DTC bus and metro. In this way a well developed public transport system that runs on zero emission will be very beneficial to control airpollution in Delhi.