How can I reduce my medical waste problem?

Two options:

  • Reduce the amount of waste you produce
  • Reduce the hazard of the waste

While it is frequently difficult to reduce hazard at a fundamental level, both quantity and hazard level of bulk waste can often be reduced by judicious segregation. That is why we are always preaching segregation at Malsparo. Keep hazardous and infectious waste separate from non-hazardous waste to prevent contaminating that waste and increasing your total waste costs. Garden-variety waste is pretty easy to dispose of.

Reducing the hazard level

Most establishments that produce waste that must be disposed of ship that waste off-site. However, the generator can sometimes do an initial treatment while the waste is still on site. While this might not be a final solution for disposal, treatment can leave the waste less risky for on-site storage and less costly for further treatment and disposal.

Focus on the Biggest Hazards

The US Centers for Disease Control and Prevention says that the biggest risk, society-wide, of medical waste causing disease comes from microbiological wastes, while sharps offer the greatest risk for injuries.

Disposal Options

  1. No treatment prior to disposal => not acceptable
  2. Minor treatment prior to disposal => change nature or encapsulate

Why is waste management difficult? Because the waste is heterogeneous. That is the biggest factor. Heterogeneity drives costs and red tape. Yes, some waste is dangerous to people and the environment. But a consistent waste stream, even if very hazardous/infectious/radioactive, can be managed. It’s when there is variety that a monkeywrench is thrown in. Variety increases costs for collection, storage, treatment, and disposal.

Surprise: it’s medical waste! Unexpected waste produces headaches and costs, too.

If we consider medical waste overall, 15 to 20 percent is regulated. The rest can be classified as Municipal Solid Waste (MSW) - what we call it in the United States. MSW is heterogeneous, too. Look at what you throw out at your home every week. It's got all manner of material in it. But, if you don't put anything in the garbage you shouldn't, it can all go to the landfill and nobody objects.

Metrics for medical waste management



lb/year, kg/year,.lb/month, kg/month, lb/patient, lb/patient day, lb/dollar orf facility revenue


Number of categories



  • Residence time - how long does the waste stay in storage? Different batches probably have different times, so calculate the average residence time and the longest.
  • Average amount of waste on premises
  • Maximum amount of waste at any time during period of interest (e.g. a year)


  • Have there been any spills or releases?
  • Has anyone been injured because of the stored waste?



  • Mass of waste processed
  • Mass of secondary waste produced
  • Utility demand
  • Effective mass yield
  • Carbon efficiency
  • Reaction mass efficiency



  • Mass of waste disposed (total)
  • Mass of waste disposed by category (e.g. hazardous, etc)

How Hard to Mitigate Hazards

Nature of waste

  • Dry solid
  • Wet solid
  • Slurry
  • Gel
  • Liguid-liquid colloid

Solid waste is the easiest to control and poses less of a spread/distribution risk than liquid or vapor. The disposal risk for a solid largely depends on how friable it is. A piece of metal isn’t likely to split unless great force is applied while a graham cracker will produce crumbs.

If your waste more resembles a graham cracker than a bar of metal, it is more likely to cause a disposal risk.

Liquid waste causes concerns for waste managers because of the risk of aerosols forming.

Liquid waste can splash and run when out of the container, but the biggest risk is if it is converted to tiny droplets that become airborne. An aerosol can travel long distances and can enter the respiratory systems of humans and animals.

Gaseous or vapor waste is usually less of a worry than liquid waste. Gases themselves disperse in the atmosphere and fall to low concentrations quickly. Unless they are toxic, they turn into a low hazard. A mist, however, can be dangerous, as it carries drops of higher density liquid. Further, biohazards can be carried on vapor streams.

Attribute How Hard Method
pH liquid easy Add alkaline or weak acid solution
pH colloid or slurry medium Add alkaline or weak acid solution
Flammable liquid hard Combustion/incineration
Corrosive liquid medium Containment or chemical stabilization
Corrosive slurry/colloid medium Containment or chemical stabilization
biohazard hard Heat or liquid disinfectant
radioactive hard Immobilization. Material will remain
Generates gas when exposed to water or air hard Isolation (short-term). Chemical transformation to less hazardous material.
sharps medium Heat disinfection followed by grinding to eliminate sharp edges