Can I get some advice on how to perform the Darth Vader test on clothing? And some standards (if possible)?
Am I doing this correctly: I empty my lungs, seal the fabric around my open mouth with my fingers as best I can, then breathe in through the mouth and count seconds until my lungs are full. For some nylon ripstop, this might be 15 seconds. For 100 wt fleece, maybe 3 seconds. For a rain jacket, I get dizzy and pass out before filling my lungs. (Kidding.) Is this more-or-less how the test works?
I suppose lung capacities and sealing ability are so different that no across-persons standards are possible, but has anyone kept track of their Darth Vader numbers for various clothing? Are there certain seconds you consider adequate for, say, light precipitation? Is there a cutoff point for what you consider adequately breathable in a wind shirt? Or too many variables here?
On a related note, someone (Dale? Justin?) was thinking of formalizing the Vader test with a constant air source and a lung capacity monitor. Any advancements on that front?
