Handwashing is defined as washing hands with plain soap (esterified fatty acids and sodium or potassium hydroxide) and water, i.e., a detergent that does not contain an antimicrobial agent or contains low concentrations of antimicrobial agents that are effective solely as preservatives. The cleaning activity of plain soap is attributed to its detergent properties, which result in removal of dirt, soil, and various organic substances from the hands.

Handwashing (Figure 1) removes loosely adherent transient microorganisms.1,25 It is indicated when (1) hands are visible dirty or contaminated with proteinaceous material, or are visibly soiled with blood or other potentially infectious material, (2) before eating, (3) after using a restroom, (4) after caring for patients colonized with Clostridium difficile, (5) following suspected or proven exposure to Bacillus anthraces (the physical action of washing and rinsing hands under such circumstances is recommended because alcohols and other antiseptic agents have poor activity against spoors), and (6) as part of two-stage surgical hand antisepsis, i.e., handwashing followed by the application of an alcohol-based hand scrub.1,25

Figure 1. How to Handwash when hands are visibly soiled?
Image: How to Handwash

Antimicrobial-impregnated wipes (i.e., towelettes) may be considered as an acceptable alternative to handwashing. However, the use of towelettes is not an acceptable alternative to hand antisepsis or surgical hand antisepsis. When done with handwashing, dry hands thoroughly with a single use towel. Organisms are transferred in much larger numbers (i.e., >104 cell) from wet hands than from hands that are thoroughly dried.18 Multiple-use cloth towels of the hanging or roll type are not recommended for use in healthcare settings.

The frequent use of plain soap and hot water can cause considerable skin irritation and dryness (irritant contact dermatitis). When performing handwashing, wet hands with warm water. Follow the manufacturer’s recommendations regarding the volume of soap use. Bar, liquid, leaflet, or powdered forms of plain soap are acceptable. When bar soap is used, soap racks that facilitate drainage and small bars of soap should be used. Occasionally, plain soaps have become contaminated with gram-negative bacilli and have caused outbreaks of nosocomial infections.26