A controlled environment that has become a major part of pharmaceutical and battery production is a dry room, which is a vapor tight, moisture reducing environment that controls and eliminates any form of dampness. These specially designed rooms are a controlled environment where manufacturers can create the necessary conditions necessary for their production application.
What is a Dry Room?
A dry room is a technologically controlled and monitored room that is designed to exclude moisture and humidity. The moisture controlling factor is dependent on the manufacturing process for which the room is designed. Computerized tools provide users with the ability to precisely determine the amount of moisture allowable in the room, a factor that is dependent on the amount of moisture and humidity a product can endure before being damaged.
The central component of a dry room is the dehumidifier that removes moisture from the room by taking in air, removing moisture, and sending dried air back into the room. The collected moisture is dripped into a collection tank or absorbed by a chemical process. The method of dehumidifying comes in several forms to meet the needs of the room.
Dry Room Construction
Dry rooms come in sizes that are determined by the size of the product to be manufactured. The floor of the room is sealed and antistatic. Wall panels, which are normally modular, are heavily insulated and fire retardant. Stainless steel or baked galvanized steel are used for the floor, walls, and ceiling.
A major part of a dry room is the filtration system that is designed to keep exterior contaminants and air out. All manufacturers use high efficiency particulate air (HEPA) filters, which remove 99% of any forms of contaminants and particulates. They are the industry standard for production, testing, and experimental rooms.
The door to a dry room has an entry chamber that is placed between the door to the exterior and entry to the room. When workers enter, they do not come directly from the outside but pass through a small, paneled enclosure that is separated from the central room and the exterior.
Types of Dehumidifiers
The type of dehumidifier determines the efficiency and performance of the dry room since it is the device that is designed to remove moisture and keep the room dry. There are several varieties of dehumidifiers as well as some that have been specifically engineered to fit unique and unusual conditions. Three common types are desiccant, thermoelectric, and refrigerated.
The desiccant method for removing humidity and moisture relies on a chemical substance that absorbs moisture in the air. A desiccant wheel made of silica gel pulls air from the room, removes moisture, and sends the dried air back to the room. Approximately 75% of the air re-enters the room leaving 25% of the air for reactivation of the system. The air that is pulled in is heated by heat boosters, which extract the moisture from the silica gel. Unlike other dehumidifiers, desiccant ones do not have a water reservoir since there is no condensation involved.
Thermoelectric dehumidifiers pull in the damp air and pass it through a cool heat sink, which condenses the air. Water from the air is accumulated through condensation and collected in a reservoir. Dry air from the process is released into the room.
Refrigerated coils or compressor dehumidifiers operate like a refrigerator and use a compressor. Hot air is drawn in the mechanism by a fan, which passes through a set of cold coils. The cooling of the air produces droplets of water that fall into a reservoir. The dried air is reheated and released back into the room.
Benefits of Dry Rooms
As products become more technical and require specially controlled manufacturing conditions, technically monitored environments, such as dry rooms, have become a critical part of product production. Many of the components and parts of computers and other technical devices require conditions that are precisely controlled to avoid contamination and damage.
Manufacturers are relying on the special conditions created by dry rooms to ensure the quality and integrity of their products.