I recently had the whole system contaminated by shoddy workmanship on our new gas manifold (see the thread titled "Ghost Peaks"). Set-up: ZB-624, 30m x 0.53mm x 3um. 35cm/min He. Oven: 40C for 10min, 10C/min to 240C for 20min. Inlet @ 160C, FID @ 250C. Headspace: 45min equil. @ 85C, 1 min pressurization @ 10psi, 1mL loop @ 95C, transfer line