If anything, these sweaters tend to run a little longer in the torso and shorter in the sleeves that "standard", but not by much. You can probably use the same size men's t-shirt and be fine.
Chest size is around the fullest part of your chest. Body length is from the neck to the waist. Sleeve length is from the center of your back, over your slightly bent elbow, and down to your wrist.
| Size | Chest | Body Length | Sleeve Length |
|---|---|---|---|
| X-Small | 20.50" | 27.50" | 33.50" |
| Small | 21.00" | 28.50" | 34.50" |
| Medium | 23.00" | 29.50" | 35.50" |
| Large | 24.50" | 30.50" | 36.50" |
| X-Large | 26.50" | 32.00" | 37.50" |
| XX-Large | 27.50" | 32.50" | 38.50" |
| 3X-Large | 28.50" | 33.50" | 39.50" |