The Volvo 700-900-850 Pocket Data Book doesn't have a torque spec for the B230F oil pan (aka. oil sump) bolts, neither does the 240 Pocket Data Book. Many will just hand tighten to what feels right. If you badly overtighten you could warp the flange. Haynes 700/900 doesn't have it, but Haynes 240 says 8 ft.lbs for all red block engines, including the B230F. Chilton's also says 11 Nm or 8 ft.lbs for the B230F engines. Edit: I just found a green manual and it also says 11 Nm, 8 ft.lbs., no other notes or procedures, just clean the surfaces and install a new gasket, lift up and tighten to spec.

I consider 8 ft/lbs a bit too light and would lean closer to 10 ft.lbs., especially if you are snugging it up when it's been weeping oil. The Volvo specs are based on using the Volvo gasket, which may be thicker than some of the aftermarket gaskets, so again, leaning to the tighter side would perhaps be advisable with an aftermarket gasket.

Gasket sealer is not called for, but if you choose to use it, only a thin and even wipe using a non-drying, oil proof sealer. If you use a sealer, again, lean to the tighter side on tightening the bolts to make sure it's squeezed out.

To help prevent the bolts from working themselves loose over time due to thermal expansion and engine vibration, many recommend using a bit of RTV on the threads (wipe any oily threads dry first). Some say it's better to use a drop or two of blue (light) thread locker, but defintely not red (semi-permanent high strength) thread locker.

Another trick to prevent future weaping is to tighten any inaccessible bolts a little extra so you can come back later after the engine has been fully warmed a few times to re-torque the rest. That's what I do with the transmission pan gasket where I tend to add a wipe of gasket sealer on both faces.

The tightening sequence with long gaskets is basically from the middle bolts out to the ends to spread the gasket evenly. I usually do a two step torque. If you use a thin coat of gasket cement it often takes a couple of passes to get the excess gasket sealer to ooze out and get the same torque all around.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now