You would think it fairly easy to set up multiple containers with different gas concentrations and similar incident radiation. (dotearth.blogs.nytimes.com)
I had been using multiple containers and lids for each of my daughter's lunches — and getting stuck with a load of dishes at the end of every school day. (copyblogger.com)
Wish I had those when my girls were little, I packed lunches everyday in multiple containers. (copyblogger.com)