5. Using Heat to Eliminate Bed Bugs

Heat is the one treatment bed bugs are not resistant to. Used safely, heat kills all life stages quickly.

Bed bugs, like many other arthropods, are unable to withstand high, dry temperatures. This information has been used to develop techniques to rid personal belongings of bed bugs using common household items, such as the clothes dryer, hair dryer, and iron. Although special equipment and expertise is needed to treat entire rooms or houses, individuals can use heat or create heat chambers to kill bed bugs on smaller items. All four strategies will be described.

Killing bed bugs with heat depends on two factors: temperature and time. The higher the temperature, the less time is needed to kill bugs. At lower temperatures, more time will be needed.

Temperature vs. time needed to kill bed bugs

Current research suggests that 122°F is immediately lethal to bed bugs, killing them within one minute of exposure. The eggs are slightly more resilient and require exposure to 122°F, so to be safe, aim for a temperature of 125°F and use the instructions below. Your choice of technique will depend on the types and size of items you wish to treat.

How to Use Heat to Kill Bed Bugs

A. Clothes Dryer

Many fabric, leather, and wool items can be cleared of bed bugs by placing items into a dryer that can heat above 125°F. Washing items first is not recommended because this increases the time needed to bring the items to the proper heat and may even spread bed bugs. Washer water temperatures are usually not enough to kill bed bugs.

i. Test the dryer for the right level of heat:

• Place 3 dry towels into the dryer (Fig. 49).
• Set the dryer on high for 20 minutes.
• Open the hot dryer quickly, place a meat thermometer in the center of the towels, and close the door.
• After five minutes, check the thermometer (Fig. 50). Temperatures of over 125°F are recommended to kill bed bugs using this technique.
• If the temperature is below 125°F, increase the heat level or the length of time in the dryer. Two hours at 115°F will be enough to kill bed bugs and their eggs.
• If 115°F is not possible, use a different dryer or a commercial Laundromat.

ii. Using the Dryer:

• If the dryer achieves the target temperature of 125°F, place infested items into the dryer using the same heat and time settings. This kills and removes bed bugs from your belongings. Do not overfill the dryer. Ensure items are tumbling! All items must reach the target temperature to achieve control.
• Items that you do not wish to tumble, such as shoes, can be placed inside a mesh laundry bag closed inside the door (Fig. 51 and Fig. 52). This exposes the item to heat and warm air circulation, but not the tumbling.

B. Clothes Iron

Some infested clothing items should not be tumble dried. For these items, place a towel over the item and use your iron’s highest steam setting to treat seams and other areas where bed bugs and eggs may be found (Fig. 53). To guard against damage, always test a small portion of the item. This technique can be applied to fabric, leather, and wool, as well as important documents, wallpaper, and window blinds, etc.

C. Hair Dryer

Forced air from a hair dryer (never a heat gun) can reach temperatures that are lethal to bed bugs, and can be used to treat infested cracks and crevices. Hair dryers are a good option when dryers and irons are not practical. This includes treating luggage, headboards, plastic furniture, and other hard items. If the item is small enough to be moved (luggage, plastic furniture), use the hair dryer in a dry bathtub or on top of a white sheet, in case bed bugs are blown off. This precaution allows easy observation. Bed bugs are no longer a threat if they fall off outdoors.

ii. Test the hair dryer for the right level of heat:

• Turn on the hair dryer, preferably on the low speed, high heat setting.
• Place a meat thermometer approximately 2 inches from the end of the dryer (Fig. 54)
• After one minute, check the thermometer. Temperatures over 140°F are recommended to kill bed bugs using this technique (Fig. 55).

iii. Treat an infested item:

• Using a low speed, high heat setting, turn on the hair dryer.
• Slowly direct hot air along the item’s cracks and crevices (Fig. 56). Lift seams and pocket flaps during the process for better access. Keep in mind that the slower you proceed with this treatment, the better.
• Keep an eye out for escaping bugs. They can be squished, vacuumed, or picked up with a lint roller.

D. Space Heater:

Professional pest management companies use expensive equipment capable of sustaining the high temperatures needed to heat entire rooms. Due to the cost of equipment and required expertise, these treatments are not feasible for non-professionals. Attempts to raise the internal temperature of the living space without professional assistance will not reach critical temperatures, and will create a dangerous situation. DO NOT try to heat your own home!!

Whole room treatments by individuals are not advised. However, heat chambers offer an alternative solution to treat medium or small items inside an enclosed area.

Heat chambers can either be purchased as “Portable Heat Chambers”, or made in a Do-It-Yourself fashion. For a discussion on several commonly available Portable Heat Chambers, see References for this chapter at the end of the book. Original instructions on how to make your own heat chamber can be found in the Reference section (Pereira, et al. 2009) but are also described here.

1. Small Capacity heat chambers operate on the same premise as large capacity treatments. See below for more details.
2. Large Capacity

Portable Heat Chambers

Portable heat chambers are available for purchase. Kits include the container to enclose items and the equipment to heat the space. Figure 57 shows a smaller portable heat chamber used for luggage and small items.

Some portable chambers are best suited for situations where large items cannot or should not be moved from their current location. Examples might include furniture in a college dormitory or senior housing location.

Other portable chambers are made for luggage and smaller heat-tolerant home items. They can be purchased for $200-500.

See this article for more information: See this article for more information 

DIY Heat Chambers

Do-It-Yourself chambers offer a cheaper alternative to large portable heat treatments. The concept is the same: build a self-contained space around bed bug-infested items and raise the internal temperature past the thermal death point (122°F). Depending on the location, heat chambers may be permanent or temporary.

Temporary chambers are made with sheets of rigid polystyrene insulation that form a box around infested items, such as beds and other furniture. Researchers evaluating this technique used the following supplies:

• Six polystyrene sheets: 8 foot by 4 foot by 2 inch thick
• 2 inch wide masking tape
• 2 remote indoor/outdoor thermometers
• 2 box fans
• 2 oil-filled space heaters (reduced risk of fire)
• A comforter or thick blanket, that can be placed in the dryer, to cover hard floors
• A white sheet to cover carpeted floors
• Surge protectors and extension cords as needed

The procedure includes the following steps:

1. Place items in a central area on top of a comforter, thick blanket or sheet larger than the heating space. Make sure that the items are positioned to fit inside the 8 by 8-foot (and 4-foot tall) chamber.
2. Place one space heater next to furniture, but not touching. Place the second space heater in the diagonal corner (opposite ends of the chamber). Try to use separate electrical circuits to avoid tripping a fuse.
3. Place box fan facing away from the heater so it will blow hot air through the space. Set up both fans so that the motion of the air will be clockwise within the chamber.
4. Place remote thermometers inside or under materials to be treated. It is important that these are not in exposed areas, but rather in hard to reach places where bed bugs tend to hide.
5. Turn on the heaters, box fans, and thermometers.
6. Create a cube around the items using the foam board and fasten them at the seams with masking tape. Start with the four walls, then add the roof. All joints should be sealed to prevent the escape of warm air.
7. Allow the chamber to heat to 125°F based on readings from both thermometers. This may take several hours. Allow the temperature to hold for a minute or more.
8. Turn off equipment and take apart the cube.
9. The one disadvantage of this less expensive alternative is the reduced portability of the chamber. Large (8’ x 4’) polystyrene boards can be difficult to transport, move up and down stairways and they present a storage challenge.

Dedicated space: Facilities with a high turnover in occupants may wish to invest in a dedicated area used for heat treatments. Homeless shelters, public housing, apartment buildings, hospitals and college dormitories are places where items can be treated on-site upon arrival as part of an intake procedure. In these settings, an individual room, storage closet, basement accessory room or even a shipping container (Fig. 61 and 62) or box truck (Fig. 63) can be fitted with materials described above to create a permanent heat chamber. This approach can save a lot of money and time in the long run.