No, you cannot release freon into the air in any situation.
You have to have an EPA certification to
- Operate freon recovery equipment
- Purchase or exchange freon and/or freon recovery tanks with certified reclaimers.
- Evacuate and recycle freon from appliances and/or vehicles of any kind.
You are only allowed to release extremely minute amounts of freon into the air, typically the inevitable release of freon when briefly connecting and disconnecting your fittings and hoses.
To make it clear, releasing freon into the air can lead to a $10,000 fine or more (last time I checked) and possible jail time, whether you have an EPA certification or not.
If caught releasing freon into the air after acquiring your EPA certification, your license will be REVOKED and you will be unable to obtain one again in the future.
Note that there are 3 different types of EPA certifications for evacuating freon. One for small and medium size appliances, one for large pressurized systems such as the ones you see on rooftops and central a/c, and one for vehicles.