The Grading System — Choosing The Best Door Hardware For Your Business
The doors on your business require more security and durability than the average residential property. After all, when business is booming, your doors may be opened and closed, grabbed and nudged, and bashed and bumped literally thousands of times in a single day. Your business is also at a higher risk for break-ins than the average residential property. Both durability and security are absolutely vital.
But not every doorknob or lock is created equal. In fact, did you know door hardware like knobs and locks are graded according to a highly developed grading system? The American National Standards Institute or ANSI, in partnership with the Builders Hardware Manufacturers Association (BHMA), has created a standardized grading system for determining the durability and security of door hardware. Their scale puts hardware into grades 1–3. Commercial door hardware should typically fall into the Grade 1 category, the highest achievement for any manufacturer. When determining a grade, ANSI uses the following criteria to determine how much stress and force a lock or knob can take before buckling.
Operational
The most basic test the hardware must undergo is operational. Does it open and close as designed? Does it latch easily when pushed closed? Does the lever retract properly? To achieve any grade, a door must withstand 4.5 pounds of closing force.
Cycles
One important factor is its cycles or how often the knob is turned all the way to fully retract the latch. Grade 1 door hardware has to be able to withstand 1,000,000 cycles. For Grades 2 and 3, it's 800,000 cycles. ANSI uses a mechanically operated test door to conduct the cycle test.
Strike Impact
To achieve Grade 1, door hardware also has to survive two strikes from 60 foot-pounds, then two 90 foot-pound strikes, and finally two strikes from 120 foot-pounds of force. That's a lot of force to withstand.
Strength of the Knob
Additionally, the knob is put under a strength test. To achieve the coveted commercial Grade 1, it has to be able to withstand 300 pound-feet of torque.
Strength of the Lever
The lever is also put to the test. To achieve Grade 1, it must withstand 700 pound-feet of torque.
Finish
The last category in the test concerns the finish of the hardware and how it holds up to environmental exposure. After all, commercial door hardware is often at the mercy of the elements and needs to hold up under some of the harshest conditions. To achieve any ANSI grade, all hardware must withstand 96 hours in a salt spray environment.
For more information, contact a commercial door hardware supplier.