No. Pennsylvania law specifically says a person cannot be forced to take a chemical test. However, you can still be charged with a DUI even if you refused the blood test. The charges can be filed as either Tier I, II, or III depending on the specific circumstances of your case. For a DUI with no special circumstances, you will be charged under a Tier I. If there was an accident the charges will be under Tier II. If your DUI is for driving while having drugs in your system, the charges will be under Tier III.
The police can get a search warrant to draw your blood for testing. If they do, they still cannot force you to give a blood sample. However, if you refuse a blood test after the police get a search warrant you might be charged with obstruction of justice, in addition to a Tier III DUI. There is also a license suspension separate from any suspension you may receive from a DUI conviction just for the refusal to provide the chemical sample for testing.