Industrial Laundry - Stages of Operation

Stages of Operation

When linen is sent to be laundered, it goes through six stages. The first three stages are called "soiled side" operations, since they occur before the linen is actually washed. The last three are called "clean side" operations, since they involve the handling of clean linen.

1. Soiled Retrieval

In this step, the institution's linens are collected by laundry personnel and returned to the laundry facility. Members of the institution's housekeeping staff will place the soiled linen at a collection point, usually by dropping it down a laundry chute. Laundry workers will then collect the soiled linen, place it in carts reserved for soiled linen and transport it to the laundry facility.

Linen retrieval poses a problem, especially in health care institutions. Soiled linen can be contaminated with bloodborne and airborne pathogens. For this reason, employees who retrieve soiled linen are required to use personal protective gear and standard safety precautions. This problem is especially prevalent in hospitals. Prior to sorting, the linen must be covered to prevent the spread of airborne germs.

2. Soil Sorting

At this stage, the retrieved linen is unloaded and sorted according to item type. Different items often require different washing formulas. Also, later stages in the process require the linen to be pre-sorted, since it is handled batch by batch. Heavy or biohazardous stains such as blood and feces may require longer wash times and stronger formulas. Thus it is inadvisable to mix different items of linen in the same wash batch. Large institutions often use a production-line method for soil sorting, with several full-time employees assigned to the task.

Since soiled linen may be contaminated with biohazards or sharp objects, employees involved in the sorting process are required to use personal protective equipment and standard safety precautions.

Smaller items tend to "hide" among larger items. For this reason, some sorting goes on during the washing, processing and packaging stages.

3. Washing

This is the stage in which the laundry is actually washed. The sorted linen is weighed according to the washing machine's load limit. Large washing machines are used, usually operated by a certified washer operator. The washer operator loads and unloads the washer, decides what is to be washed according to the laundry's schedule, and monitors the chemical levels in the water. Since modern tunnel washers monitor their own chemical levels and unload linen directly into the laundry's "clean area", the operator is required only to load the linen.

Proper washing depends on five factors: Water quality, mechanical Agitation, Time, Chemical concentration and Heat. Washer operators use the acronym WATCH. These five factors work together. The purer the water and the fresher the chemicals, the cleaner the laundry will be. Mechanical action exposes the surface area of the linen to the water and chemicals, ensuring that the item is thoroughly soaked. Mechanical also tends to dislodge stains. Heat helps the chemicals to react with the stains. The longer the item is exposed to heat, chemicals and mechanical action, the cleaner it will be.

Over the past twenty years, many industrial laundries have switched from conventional washers to tunnel washers, also called continuous-batch washers. Since tunnel washers don't have to be stopped for loading and unloading of linen, they provide a more continuous flow of clean laundry. Higher-volume facilities, which may process over 15,000 pounds of linen per day, often rely heavily on tunnel washers.

4. Processing

In this stage, the clean linen is dried, ironed and folded. Some items, such as towels and blankets, are put through a dryer until they are no longer damp, then sent to mechanical folders. "Wetwork" items, such as sheets, are sent through steam-powered ironers which dry, press and fold them.

Dryers use hot air and mechanical action to evaporate the moisture and chemicals from the linen prior to folding. Heated air is forced through pores into a spinning central cylinder called the drum. As the cylinder constantly spins, the linen inside tumbles, exposing the surface area to heat which evaporates the moisture. The air temperature must be carefully controlled. If it isn't hot enough, the linen won't be thoroughly dried. If it is too hot, the linen may overdry, damaging the product and creating a fire hazard.

Ironers use heavy steam-heated rollers to dry the linen while pressing out wrinkles.

Folders use mechanical action to fold the linen into shapes that are easily stored and handled. Folders come in two varieties: large-piece for blankets and other large items, and small-piece for smaller items such as towels or pads. The more compact the shape into which the item is folded, the greater the amount of linen that can be packed into a limited storage space.

Some items, such as wash cloths, may be too small to be handled mechanically. These items must be packaged by hand.

5. Packaging

In this step, the processed linen is prepared for delivery. Individual orders are filled, based on the needs and requests of the laundry's customers, then sent to the laundry's main distribution points and storage areas. Linen not used for orders is placed in storage areas, giving the facility a reserve of clean laundry.

6. Distribution

In this step, trained delivery people transport the clean linen back to the customers. This is a skilled position, since the delivery person must have a thorough knowledge of both laundry operation and the principles of good customer service. In hospitals, delivery people must be familiar with patient relations, confidentiality policies and hospice. Large institutions will usually employ several full-time delivery people.