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Substitution and Engineering Controls

Substitution: Replace the Hazard

Substitution is replacing something that produces a hazard (similar to elimination) with something that does not produce a hazard.

Examples include:

  • Using non-toxic or less toxic chemicals
  • Upgrading aging equipment and devices with newer equipment or devices
  • Replacing latex gloves with non-latex gloves
Hospital sharps container with lid open.

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Engineering Controls: Isolate People from the Hazard

Engineering controls are designed to control the hazard at the source before it comes in contact with the worker through isolation or enclosure of the process. They are often an integral part of the device or equipment (built-in feature).

Examples include:

  • General dilution ventilation and local exhaust ventilation
  • Safety engineered devices: needleless device systems, scalpels, lancets
  • Equipment guards/shields/lids
  • Rubber dam/sheath placed around tooth/teeth to minimize droplet and aerosols in dentistry; high volume evacuations
  • Sharps containers
  • Closed-system drug transfer devices (CSTDs)
  • Replacing manual cleaning of instruments with automated cleaning washers
  • Scavenging systems, fume hoods, biological safety cabinets (BSC) for hazardous drug preparation and transfer, air purification
  • Anesthetic gas scavenger systems
  • Patient lifts