My adorable son is now four months old, still a tiny bundle of joy. I look forward to us venturing outside for summer fun, but what if the pollution is bad that day? I desperately hope we don’t have another January-ish “airpocalypse” of extreme air pollution keeping our kids inside. I hope everyone is taking long summer breaks amid cleaner and greener pastures. But for us staying here in Beijing, what pollution guidelines should we follow when kids are at camp or playing outside?

One major debate is choosing when to keep your children inside. I think a good baseline is to follow the action plans that most international schools use, with a usual AQI cutoff of 200 triggering cancellation of all outdoor sports — assuming no protective masks would be worn. We use these cutoffs because children’s lungs are still developing until around age 18, and as they exercise they breathe much deeper than usual, thus potentially causing more damage.

What about air pollution masks? Since I last wrote about air pollution for BeijingKids, there was a very interesting new study published which provided the best evidence so far that wearing an N95 mask does indeed help to reduce air pollution’s unhealthy effects. They tested people walking around major roads in Beijing and had half of the group wear a 3M N95 mask. Those who wore this mask had improved blood pressure as well as heart rate variability, both of which are signs of damage from pollution.

I think this and other studies should convince parents to consider buying masks for their children, especially when air pollution levels are over 200 AQI. The key is to use a real N95-rated mask. N95 literally means that mask is certified (in the USA) to filter out 95% of particles (PM) smaller than 2.5 microns — usually much smaller, at PM0.3. This means if the AQI is a crazy-bad 500, your mask is filtering 95% of that, and your actual breathed air is much healthier. But you must find a mask that is rated N95, not just a cotton mask or even just a blue surgical mask.

The other major issue here is fit: even a small amount of air leaking around the corners makes any mask basically worthless. Unfortunately, there is no easy answer as to the best brand and model for kids.  The 3M N95 rated masks are always considered the first choice “gold standard” in research tests. April Gourmet, Jenny Lou’s and many other places sell them, as do all of our clinic pharmacies. The 3M company has an 1860S child size, but I have only seen this in the USA. Many parents have tried Totobobo masks down to toddler years as they can be cut down to children’s faces, and they also aren’t as scary looking as a standard mask. Others have tried Respro, but their own blog doesn’t recommend any of their models for children under 11. Others seem to like the Vogmask series as they are comfortable for smaller faces. However, many parents report varying degrees of success for all of these. But don’t fret, as I am personally aware of at least two companies feverishly working on children’s masks. Even as we go to press, there may be at least one company making them. (UPDATE: starting next month, Vogmask will be selling the first consumer line of masks designed for children of all ages, officially tested over 95% protection. Stay tuned for a review…)

If your child is planning any overnight trips or camping adventures, I think it’s wise to give them a good air pollution mask just in case. And if their day trip plans come into question because the air is bad, you don’t always have to cancel their fun — consider wearing a mask while they play. I know this entire idea of wearing masks is very tiresome and even controversial, and it certainly puts a damper on outdoor play. But as parents it’s our moral responsibility to safeguard our children’s health while living here in China.

(This article was originally printed in the current edition of Beijing Kids magazine, where I am a contributing editor. You can click here to read the rest of my BeijingKids “The Doc Is In” columns.)