View Full Version : How do I determine the number of 1" holes

08-23-2005, 02:12 PM
I need to determine how many 1" holes are 16% of the total surface of a 28" x 19" box.

08-23-2005, 02:23 PM
What is the surface area of the box? (Note: If you mean "box", there needs to be a third dimension. With only two dimensions, you get the "area" of a rectangle.) What is sixteen percent of that amount?


08-23-2005, 02:39 PM
It's an animal (pet) kennel that measures 28" x 18" x 19".

The USDA requires there be ventilation openings located on all four walls of the primary enclusure and the ventilation openings on each of the four walls must be at least 8 % of the total surface areas of each such wall, and the total combined surface areas of the openings must be at least 14% (so I am asking for 16%) of the total combined surface area of all the walls of the primary enclosure. The holes are to be 1" in size.

Thank you for your help. I'm hoping for a simple formula that will help us in the future with all size kennels.


08-23-2005, 03:00 PM
1) What are the dimensions? Which one is HEIGHT?
2) How did you get from 8% to 14%? Whether it is 8% of a pin head or 8% of the Pacific Ocean, it is still only 8%. The percentage doesn't grow with the total surface area. Wait, maybe it just means you can't put all the holes on one side. 14% is really the goal, but you have to spread it around.
3) No hols in top or bottom?

1" diameter circle ==> pi*r<sup>2</sup> = 3.14159*(0.5 in)<sup>2</sup> = 0.785 in<sup>2</sup>

08-23-2005, 03:19 PM
You will have two different size sides: 28x19 and 18X19
If the diameter of 1in then the area is (pi/4) sq. in.
16% of 28x19 is 85.12 or 108.3 holes.
16% of 18x19 is 54.72 or 69.67 holes.

08-23-2005, 03:45 PM
In answer to your questions:

1) The dimensions are 28" Long x 18" wide x 19" high.
2) The holes are on 3 sides actually, as the front of the kennel is a wire gate closure.
3) There are no holes in the top of bottom.

Thanks again for your assistance.

08-23-2005, 04:48 PM
Well, then PKA was right on. I still don't know how he knew which was the height.

That seems like an awful lot of holes. One may need to worry about structural integrity, but that's a chat for another foum.

08-24-2005, 12:29 AM
TK may be right about the structural integrity with all those holes. I'm not sure of proper interpretation, but please consider this: the open front may count as most of the ventialtion rqd to meet the 14% goal. If so, then the remaining three sides need only meet the 8% goal -- half the number of holes PKA stated.

Just a thought...