Hi @RyanFreeborn Welcome to the forum!
So this has been a topic Ive been following pretty closely. The problem is that Automotive manufactures refuse to release any information or training on the seam construction methods used on airbag seats. The manufactures say to buy new covers from the dealer. But we all know that doesn't solve the problem. Especially when they stop making covers for older cars.
There are lots of opinions on this topic. Some say to use a thinner thread. Some say that airbags are so powerful it doesn't matter it will just rip through the fabric. Ive even heard of some people using cotton thread instead of polyester. These are just things I have read and heard. Most of the things I do are on older cars but this is becoming an unavoidable problem and I have the same concern you do guys do.
My advice is that anyone how wants to do airbags seats... Have a lawyer draft a universal waiver to use for customers that are willing to sign away all liability and understands that the seat has been modified from original specifications. This will cost a few hundred dollars but is money well spent.
Here are 2 articles disusing this. You might be interested in reading.
http://www.thehogring.com/2016/02/10/sh ... ts-either/
http://www.thehogring.com/2012/03/03/wa ... his-cover/
Hope this helps guys!