DIY Guide: How to Create Your Own Air Filter

Get a 20 in × 20 in (51 cm × 51 cm) box fan and a MERV 13 filter. Purchase these items online or from a hardware store. While any MERV 13 filter will suffice, consider upgrading to a HEPA filter for superior air quality. If you don't have a standard box fan, any flat-faced fan will work as long as you can place a filter over the blades.

• For non-box fans, the filter doesn't need to fit perfectly over the blades.
• If you're using a round table fan or one with a rounded cover, remove the casing to expose the blades. If there's a central peg, use a handsaw to remove it and keep the fan flat.

Position the filter behind the fan with arrows pointing towards it. Place the filter at the rear of the fan so that when the fan is switched on, it draws air through the filter. Use the arrow on the filter to determine airflow direction.

Secure the filter to the fan using duct tape. Apply duct tape or a strong adhesive around the edges of the filter and fan to ensure a tight seal. Use additional tape if needed for round or irregular-shaped fans.

Place the filter-equipped fan in a closed room and activate it. Ideal for smaller rooms like bedrooms, turn on the fan to initiate air filtration, removing harmful particles. Replace the filter every 90 days for continued effectiveness.

Acquire a 20 by 20 in (51 by 51 cm) box fan

and 4 MERV 13 air filters. Purchase the necessary materials to construct a standalone air purifying box, including a 20 by 20 inch box fan and four MERV 13 air filters, available online or at a hardware store.

Prepare a 20 by 20-inch cardboard sheet. Use corrugated cardboard or poster board if necessary. Trace and cut out the cardboard based on the size of an air filter.

Securely assemble the 4 air filters and cardboard. Arrange the filters in a square, ensuring the arrows on each filter point inward. Tape the cardboard to the filters to form the base.

Attach the box fan and secure it with tape. Position the box upside down, place the fan on the open side, and tape it in place. Cover any gaps between the fan and filters with tape.

Place the air purifier in a central, poorly ventilated area. Position the fan on top, plug it in, and let it clean the air. Replace the filters every 6 months for continued effectiveness.

Create a small groove at the top edge of the bucket to accommodate the fan cord. Use a utility knife or wire cutters to make a notch approximately 1/4 inch by 1/2 inch (0.64 cm x 1.27 cm) in size. Test the notch by attempting to pass the fan's electrical cord through it.

• Ensure the cord remains securely in the notch, away from the lid.

Install the fan into the lid and the bucket. Insert the fan through the lid with its blades facing upward. Position the top section of the fan's case on the bucket's surface so that the fan blows air back into the room. Lower the fan's base into the bucket, keeping the cord in the previously cut notch. Plug the fan into the nearest electrical outlet to initiate air purification in the room.

• Replace the filter every 3 months to maintain clean air.