Even torque sticks shouldn't be trusted, but at least they're better than hoping the psi they've got their air supply set at limits their air wrench. I always insist on hand torqued, but even then you can't trust the word to get to the tire tech or that the tire tech will have the time and inclination to do it by hand.

I've had a couple of occasions where a tire shop said they used a torque stick, but I suspected they didn't or at least it wasn't correct. Instead of the typically spec'd 65 ft-lbs for my 900s (front and rear, same for most 700s, but for your 240 is typically 85 ft-lbs front and 70-100 rear -check your year and wheel/rim type), which I noted for them both inside the wheel covers and which Volvo also has stamped on the front hubs (which are the most critical), I variously measured they'd torqued them from 85 to over 125 ft-lbs. I was not amused, and later told them so. Their excuse was that the torque sticks may not have been recently checked for calibration and replaced as needed (yeah, like some tech is going to spend his own money buying new tools he doesn't think he needs).

The way to accurately check what a shop has done is with a bar torque wrench. Carefully note the original wrench position when tensioned forward then back off the wheel nut a bit and re-tighten, noting the torque reading you reach at the precise original angle, while keeping the wrench in motion as you move just past that point. Repeat and average if you're a purist. As noted, I was mildly shocked how far off they were, well at least disappointed as I expected better of them. None were even close to correct. Worse still was the variability around the wheel.

Torque sticks usually come in 10 nm increments, normally starting at 90 nm (65 ft-lbs), which is the 700/900 spec and not an overly common torque compared to many other vehicles. If their kit doesn't have the smallest stick or if they're too lazy to look for it (or look it up in a chart) then they may use the next size up, or worse guessing. Also, if it's well used, it's quite likely out of calibration, which a good tech is supposed to occasionally check, but I suspect rarely happens.

Torque sticks also have to be used correctly. If the wheel nut is driven in at full speed and full air pressure all at once without pausing as you go, momentum and other factors will result in overtorquing, which may be significant as I and others have observed.

For our RWD rotors, being evenly torqued around the rotor is more important than the actual torque in terms of minimizing rotor warping as long as the nuts can't come loose. Wheel nuts likely won't come loose for anything above 50 ft-lbs, depending on whether they're steel or alloy rims and how clean the threads and sockets are. I'll also note here that a clean and dry thread is required for proper torquing. Having rusty rims, leaving grunge on the threads or hitting the threads with something like WD-40 to loosen grunge without wiping it off, can all result in significant overtorquing or uneven torquing.

Even a click torque wrench should occasionally be double checked against a bar or other torque wrench, also leaving the tension spring completely relaxed when stored. For bar torque wrenches, make sure the pointer is at zero when you start out. Bending the pointer to zero is an acceptable re-calibration if you don't have to bend it too much

Anyway, that's my full two-bits on the subject.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now