n mid-December President Donald Trump signed an executive order directing the US attorney general to move marijuana from Schedule I to Schedule III, which is the same category for medications such as acetaminophen with codeine. While the executive order does not legalize all cannabis sales and use, the move should allow cannabis businesses to take federal tax deductions and may eventually pave the way for marijuana owners to take advantage of many financial services that are currently unavailable or difficult to obtain, even in states like Alaska that have legalized the leafy green.

The challenge of working in this gray-green area is in part what drove Catalyst Cannabis founder and CEO Will Schneider to start investing in real estate projects; it was a way to securely reinvest capital from his cannabis business. In the architecture and engineering special section, Senior Editor Scott Rhode in “Cash to Cannabis” quotes Schneider saying, “We’ve been focused on making a portfolio that has hard assets in it. The weed industry… could go away… but real estate is here to stay. It’s nice to start putting that in the bank account.”

That whole article is excellent, but another aspect of owning a marijuana business especially stood out as I read it through the first time. Rhode writes, “Air handling was also a major concern on the other side of the building [from Mexican restaurant El Green-Go’s]. Schneider says mechanical design had to carefully collect, filter, and separate cannabis odors from the retail shop. Indeed, the funk on the sales floor is overpowering, but not even a wisp escapes outside the door.”

While national policy is the only answer to some of the cannabis industry’s challenges, engineering is the only fix for others. There’s a joke in the article about taco and weed businesses being a natural match—and for some they undoubtedly are—but there are also those in Alaska who may wish to visit one business without experiencing the other. It’s the HVAC system that allows all members of the public to be comfortable within the building, no matter which business they’re inclined to visit. Politics drive what is and isn’t legal—but it’s a whole other skill set that engineers good neighbors.