For the Spring 2021 class project of the Engineering 535, Development Technology class at Cal Poly Humboldt, we were tasked with designing, building and testing an affordable and easily replicable wildfire smoke mitigating air filtration system for low income families or individuals. The Do It Yourself (DIY) air filter was deigned to efficiently filter particulate matter in wildfire smoke and PM 2.5 (particulate matter 2.5) from other indoor pollutants. The ease of use for people with physical disabilities was also considered as seen in the inclusion of swivel caster wheels at the bottom of the air filter. The efficiency and cost effectiveness of the DIY air filter was found to be equivalent to that of a typical off the shelf air filter system.
MERV13 filters taped together to create a housing space.
Use duct tape to secure the 4 pieces of the ACE 14*20*1 high performance pleated MERV 13 air filters together to create a four-walled filter housing.
Cutout two cardboard or hard boxes in a square shape, measured to the size of the bottom or top part of the filter housing.
Swivel Caster Wheels glued to the bottom of the hard box cutout.
Secure each swivel caster wheel on each corner of one of the cardboard cutouts using Gorilla Glue. Set it aside and wait until the wheels are firm on the cardboard and the glue completely dry.
One side of the box fan fitted through the hard box cutout.
Measure the diameter of the airway of the box fan to the remaining square cardboard cutout to ensure that the circular middle part of the box fan can tightly fit through the hard box cutout.
Cutting off the extra stand on the fan so it can fit through the hard box cutout.
Use a handsaw to cut off the extra box fan stand length at the bottom, on the air inflow side of the fan to ensure that the fan can fit well in the circular hole on the hard box cutout. This step is only necessary if you are using the same type of fan.
A box fan fitted through the top hard box cut out.
Insert the circular middle part/airway of the fan through the hard box cutout. Make sure it is tight in the circular cutout hole. Make sure the fan is inserted with the air outflow on the outer top and inflow on the inner side of the filter housing. User duct tape to further secure the fan on the card board without blocking the fan airway.
Cover the top part of the filter housing.
Cover the top of the filter housing with the hard box cutout that has the fan inserted in it. Ensuring that the fan switch and the air outflow are on the outer side of the filter housing, use duct tape to secure the cardboard with the fan on top of the housing, leaving no air spaces that are not part of the fan.
Swivel caster wheels secured on the bottom hard box cutout.
Check to see if the Gorilla Glue on the swivel caster wheels is dry and that they are secured on the hard box. If dry, make a one inch (1") slice on the side of hard box that has the wheels, enough to take the fan power cord through from the inside of the housing. Take the power cord through the slice and secure the slice with duct tape if needed.
To block off the bottom part of the filter housing, use duct tape and secure the cardboard with the strollers at the bottom of the filter housing, making sure that the wheels and the fan power cord are on the outer part of the bottom of the filter housing.
Looped fiber string for a handle.
For easy mobility, secure a fiber string with a loop at the bottom of the filter housing using duct tape.
Keep the makeshift break on the side of the filter when moving it and between wheel and the metal to break.
If your wheels don't have breaks, cut a small piece of rubber or styrofoam, tie it to a string, secure it at the bottom of the housing near one of the stroller to create a make shift break such that the filter doesn't keep moving when you don't want it to.