Process Parameters 
===================

	* Reflow (lead‑free, reference):
		* Preheat 120–170 °C / 60–120 s
		* Soak 150–180 °C / 60–120 s
		* Peak 235–250 °C / 10–40 s above liquidus
		* Record actual values per alloy/parts
		
	* Selective/wave:
		* Preheat per machine
		* Solder temp ~260 ± 5 °C
		* Contact time 2–4 s (layout/part dependent)
		
	* ESD environment:
		* 40–60 % RH
		* 20–26 °C
		* Grounding resistance < 1 GΩ
		* test wrist straps daily
	
	* AQL (if applied):
		* Critical 0.65
		* Major 1.0
		* Minor 2.5 (define per project)