What is a Hand Dryer?
A hand dryer is a device designed to dry hands after washing, using airflow without requiring physical contact. They are commonly installed in public restrooms within commercial facilities, restaurants, and other high-traffic areas. Compared to paper towels, hand dryers are cost-effective and promote quick drying.
Uses of Hand Dryers
Hand dryers are strategically placed in hand washing areas, mainly in restrooms, to enhance cleanliness and user convenience. Unlike paper towels or cloth rolls, hand dryers reduce maintenance costs by eliminating the need for towel replacements and waste disposal. Furthermore, as hand dryers do not produce paper waste, they contribute to environmental sustainability.
Hand dryers are commonly found in:
- Restaurants
- Commercial facilities and department stores
- Office buildings
- Public transportation hubs
- Medical facilities
- Welfare centers
- Food production factories
- School cafeterias
- Kindergartens and nursery schools
Principle of Hand Dryer
Hand dryers operate by using sensors to detect hands and blowing air to dry them. There are two main types of mechanisms: warm air and jet air. Warm-air hand dryers use warm air to gradually evaporate water, typically taking 30-40 seconds to dry hands. Jet-air hand dryers, on the other hand, use high-speed air to blow water off in about 5-9 seconds, making them ideal for busy restrooms with high user turnover.
Within jet-air dryers, there are two varieties: the standard type, which blows air to dry hands, and the suction type, which additionally draws in air to minimize water droplets and airflow scatter. Standard jet dryers require users to move their hands side-to-side through the dryer, while suction dryers have users insert their hands vertically, reducing splash and ensuring a cleaner drying process.
Types of Hand Dryers
Hand dryers come in various designs, sizes, and functionalities, catering to different usage needs and installation environments.
1. Size
Hand dryers are available in standard and slim designs to accommodate different spaces. Slim models are ideal for compact areas, while more powerful models, typically in standard sizes, offer faster drying times. Some models are designed for countertop installation, especially for private or multipurpose restrooms, while commercial units are usually wall-mounted.
2. Functionality
Hand dryers primarily operate on either a warm-air or jet-air mechanism. Jet-air dryers are preferable for locations requiring quick drying times, such as high-traffic restrooms. Among jet dryers, some only blow air, while others have a suction feature to contain water droplets.
In a standard wall-mounted jet dryer, air blows from both sides, enveloping the hands. Compact versions blow from above, directing air across the hand surface for uniform drying. For environments with heightened hygiene requirements, high-performance models may include sterilizing lights or continuous air-cleaning functions to maintain a clean air environment around the unit.