Low humidity causes ions in the air and surrounding materials to become more negatively or positively charged. When ions get drawn to each other, they attract, repel or cause sparks. Flammable materials--- including solids, liquids or gases---can collect a huge amount of static electricity in low humidity. Air moisture can be balanced with humidifiers; however, having balanced humidity in a room does not guarantee that excessive static electricity won't build up.
In cold and dry winter months, heaters cause skin and hair to become dry. According to the website School For Champion, dry hair and skin are more prone to generate excessive static electricity. When dry skin or hair gets in contact with other materials capable of storing static electricity, electrical charges react and disperse. Keeping the body moisturized during the winter season can prevent too much static accumulation.
School For Champions also states that a person sitting on an object such as a car seat or computer chair for a long time can collect excessive static from the seat. When he opens the car door or touches something without grounding, the static electricity that accumulated disperses quickly, sometimes causing severe pain. Having antistatic mats or sprays, humidifiers or ionizers can help limit this excessive accumulation of static.
According to the website Electrostatics Net, wearing rubber-soled shoes on woolen carpet causes electrically-charged particles to build up and generate static. Materials, such as plastic, rubber, rayon, and polyester, are also prone to generate excessive static electricity. To avoid excessive static generation, floors and furnishings should be made with non-polymer materials, such as wood, cement, metal, cotton and silk.