Military Medical Technology Online

Weeding Out the Waste

By Patrick Chisholm

Proper handling of hazardous medical waste is difficult, time-consuming, expensive and necessary to prevent the spread of contaminates and keep health care workers safe.

The hepatitis B virus (HBV) is the Number one occupational infection among health care workers. Each year, an estimated 12,000 health care workers whose jobs involve exposure to blood are infected with HBV, according to the Centers for Disease Control. Health care workers are also at risk of exposure to other bloodborne pathogens, including the human immunodeficiency virus (HIV), malaria and syphilis. And of course less serious conditions such as the common cold, pinkeye (bacterial conjunctivitis) and the flu are ever-present risks as well.

This is why the proper handling of medical waste is so important. Diseases can be spread through used “sharps” (e.g., hypodermic needles and syringes), items contaminated with blood and human organs. Infection or disease can enter the body through puncture wounds or broken skin. Infectious agents could splash into the eyes or mouth, be inhaled, or be inadvertently swallowed after handling contaminated articles.

Untreated medical waste can put refuse workers at risk as well—at the medical facility, at the landfill, or any place in between. They could be exposed to needles, human blood or other disease-carrying mediums.

Vast regulations govern the proper handling of medical waste. In the Army, there are Medical Department Activities (MEDDAC) regulations. “There are also regulations issued from multiple levels, such as the North Atlantic Regional Medical Center (NARMC) regulations,” said Lieutenant Amber Hayden, chief of environmental health at Keller Army Community Hospital (KACH), West Point, NY. “And there are MEDCOM regulations from our Medical Command. So, it’s similar to federal, state and local regulations.”

In addition, military medical facilities still have to follow actual federal, state and local regulations.

According to the Environmental Protection Agency, medical waste is typically described as any solid waste that is generated in the diagnosis, treatment or immunization of human beings or animals, or in the production or testing of biologicals, including but not limited to:

• blood-soaked bandages
• used culture dishes and other glassware
• discarded surgical gloves
• used surgical instruments, such as scalpels
• needles used to give shots or draw blood
• cultures, stocks and swabs used to inoculate cultures
• removed body organs (e.g. tonsils, appendices, limbs, etc.)
• lancets, the tiny blades used for finger pricks

Medical waste is often separated into infectious medical waste and noninfectious medical waste at its point of origin. This particularly applies to medical facilities on ships, in order to reduce the amount of infectious medical waste that must be processed and stored on board.

Noninfectious medical waste typically can be disposed of in the same way as normal garbage, as municipal solid waste. Examples of noninfectious medical waste include used personal hygiene products, such as facial tissues and sanitary napkins; absorbent materials (not including waste from isolation rooms) containing small amounts of blood or body fluids; disposable products used for routine medical or dental procedures, such as rubber gloves, tubing and catheters; empty pill bottles; intravenous (IV) bags; expired, unused culture tubes and plates; packaging; and overwrap.

Before treatment, regulations stipulate that infectious medical waste or regulated medical waste (RMW) must be placed into sharps containers or plastic bags that are clearly distinguishable from containers of municipal solid waste.

Treating medical waste includes rendering it unidentifiable and non-infectious prior to disposal into the municipal landfill. Devices to achieve this include incinerators, steam sterilizers, plastics waste processors, shredders and pulpers.

There are regulations on the types and colors of containers to be used for medical waste, in order to handle the waste in a safe and efficient manner, said Victor Anderson, president of Solutions Incorporated, a producer of medical waste containers. “For example, a container can’t have a way for the waste to leak out. And there are guidelines in place for the thickness of the container.” He said the guidelines mainly come from the Occupational Safety and Health Administration and the Department of Transportation. “If containers are transported to a treatment facility or some sort, they have to meet DOT requirements.”

He added, “There are colors that differentiate the different types of waste or the different types of medical waste, such as yellow for chemo, gray for path[ological] or red for RMW.”

At KACH as in many other hospitals, there are special containers just for sharps, which are locked to the walls in the hospitals. This is a requirement in order to prevent the possibility of anyone stealing the used syringes. And pathological waste, such as body tissue, often gets put into a specific freezer. The frozen materials are then picked up for disposal.

Personal protective equipment consists of gloves, in order to prevent against anything that might enter into an open wound. Items such as aprons, face masks and goggles are not required for routine handling of RMW but are available at KACH for other uses.

Biomedical material is classified as “hazardous waste” or “hazardous material” for transport. “Hazardous material is anything that could cause unreasonable risk to health, safety, and property when transported,” said Hayden. “Even something that is flammable can be considered as hazardous material.” She said that liquid waste from X-rays and mammography needs to be collected and filtered because the silver in it is toxic.

Items such as expired pharmaceuticals and expired Thin-prep is considered hazardous waste. There are accumulation points throughout the hospital for those. At KACH, explained Hayden, “Most hazardous wastes are picked up by the solid waste management branch, which is under the environmental management division at the installation level, and those are packaged up, labeled and transported out from our site through another contract that the installation handles.”

The incineration process consists of mixing the waste with water, crushing it, and exposing it to extremely high temperatures. “Basically it’s broken down into one uniform consistency and then placed into the landfill, and the water goes to the water treatment plant,” said Hayden.

Some hospitals have waste disposal machines on site, and others rely on contractors to transport the waste and dispose of it off site.

At sea, ships are required to package and label infectious medical waste that is to be transferred for disposal ashore, placing sharps containers in a separate container from other waste (either a puncture-resistant container or impervious plastic bag), according to the Afloat Medical Waste

Management Guide, prepared by the Chief of Naval Operations (CNO) Environmental Readiness Division, a.k.a. N45 (formerly the CNO Environmental Protection, Safety and Occupational Health Division). Rigid or semirigid, leak-proof containers are used for infectious medical waste transport.

But if retention of infectious medical waste endangers the health or safety of personnel on board or compromises combat readiness, the guide states that the commanding officer or master may authorize overboard discharge beyond 50 nautical miles from shore. “Discharged waste must not contain plastic or sharps and must be steam sterilized, rendered unrecognizable, properly packaged and weighted for negative buoyancy,” it advises.

Medical Waste in the Field

Most medical waste among U.S. forces in Iraq and Afghanistan is disposed of through portable incinerators.

In 2003, when Hayden was in Iraq, there was no formal process for handling medical waste. “When we first started on ground, there were no real systems for handling regulated medical waste. But eventually things got squared away, through lining up contractors to bring the waste to incineration sites.”

One of those incinerators is the MediBurn portable incinerator, manufactured by Elastec/American Marine. Currently more than 60 of them are being used in Iraq and Afghanistan, owned by either the U.S. military or contractor Kellogg Brown & Root. It is a small incinerator that runs on diesel fuel and 220 volts of electricity.

Unlike larger incinerators, which may require a concrete pad, piping for the fuel supply, or extensive measures to secure the electrical supply, “this unit can actually be set in place, on level ground, hooked up to a generator and run directly out of the box. It’s one of the key features of the unit,” said Jeremy Pretzsch, sales representative at Elastec/American Marine.

“It can be set in place inside of a building or under a shelter. Of course, you have to have enough room around it for safety, as well as venting for the emissions,” he said.

Approximately 6 feet long, 9 feet high (with stack), and 4 feet wide, the MediBurn has a dual chamber design so that it burns the emissions and smoke in addition to the waste itself.

The incineration process involves placing the medical waste into the bottom chamber. The user selects the amount of time desired for the unit to run—anywhere from 30 minutes to three hours. Then, the unit goes through a four-cycle process. The first 30 seconds are called the purge cycle, where it purges out any potentially combustible gases that may have built up in the unit.

Pretzsch explained, “After the first 30 seconds, the upper burner ignites and preheats the upper chamber to a preset temperature. So when the lower chamber ignites, after a certain amount of time, the upper chamber is already hot. The emissions go through that upper chamber and get burned completely. There’s nothing going out of the stacks; in other words it’s not going through a cold chamber and just rushing straight out.”

The third part of the cycle is the burn time, when the medical waste is actually destroyed. The fourth part of the cycle is called the cool-down stage, when the burners shut down and only the fans continue to run. They cool the unit to about 200 degrees

Generally, there’s about 3 percent ash left when the process is finished. “At that point it’s sterilized, so it’s safe to dispose of in a dumpster or any receptacle,” explained Pretzsch. It burns at a thousand degrees Celsius. “If you don’t maintain a constant temperature, then you’re not going to be able to destroy most pathogens and other types of diseases.”

The weight of the unit is about 1,900 pounds. Shipping weight is 2,400 pounds.

Burn-Free Disposal

Another technology processes regulates medical waste through steam sterilization, without producing toxins or other harmful byproducts that could potentially damage the environment. It is called the SSM-150 system, produced by Red Bag Solutions. It is designed to process about 600,000 pounds a year.

The company has units in Navy and Air Force facilities in Guam, as well as in Veterans Administration (VA) facilities in Baltimore, MD, Hines, IL, and Richmond, VA.

At the Baltimore VA hospital, Red Bag Solutions report that “We’re handling their entire waste stream. It’s not only red bag material, but also regular trash and recyclable materials. The housekeeping staff at the hospital collect the various waste streams and put it in central storage areas on the different floors. Our guys pick it up from the central areas, we segment it, process what’s hazardous, and haul off what can’t be processed as hazardous material.”

Once the waste is collected and segmented, the operator places the red bags inside of the system, and shuts the door. “We began by introducing steam to the cycle, then add water and take the temperature to 270 degrees Celsius under pressure. Then the cutting system cuts the waste up into very small, unrecognizable pieces,” said Chris Tamburo, Red Bag’s regional sales manager.

The SSM-150 system also handles Health Insurance Portability and Accountability Act (HIPAA) materials that are patient-sensitive, such as wrist bands, patient records, pill containers, CD-ROMs, or anything else that contains a patient’s name.

“Between the water, the steam and the cutting, the end product is considered unrecognizable by any current standards,” said Tamburo.

The entire cycle takes about a half-hour, during which time about 100 pounds can be processed (i.e. 200 pounds per hour). “In that half-hour only six minutes are dedicated to the loading of the system. It allows our operators to go and collect more waste from the patient floors, and by the time they get back they are usually ready to run another cycle,” he explained.

Note that there must be an adequate water supply to meet the operational needs, so it may not be suitable to very dry locations such as Iraq and Afghanistan.