Basically, DP Rating measures the strength of a door. This number will tell you how well your door will stand up to high winds. DP ratings represent three performance elements — structural load, water resistance, and air infiltration resistance. The higher the DP Rating the stronger the door. The DP rating is a “pounds per square foot” number
Note, the DP rating does not imply that the door is“impact-resistant”, which is a different test to determine if a door can withstand a direct and forceful impact without breaking.
A typical hurricane has sustained winds of 100 - 150 mph. Winds in some stronger storms may exceed 200 mph.
Hurricane classifications:
- Category 1: 74-95 mph
- Category 2: 96-110 mph
- Category 3: 111-129 mph
- Category 4: 130-156 mph
- Category 5: 157+ mph
To oversimplify it, theoretically, a DP30 rating should survive a Level 3 hurricane, a DP40 a Level 4 hurricane, and DP 50 a Level 5 hurricane.