DEN 101 | WEEK 3

What defines a hazardous chemical?

Any chemical that can cause a physical or health hazard (ignite, react/explode, be corrosive, or toxic).

What are the three primary exposure routes to chemicals?

Inhalation, skin contact, and ingestion.

What is a corrosive chemical?

A chemical that can destroy skin tissue.

What distinguishes acute chemical toxicity?

High level of exposure over a short period, causing an immediate reaction.

What distinguishes chronic chemical toxicity?

Many repeated exposures at lower levels over a longer period, with different symptoms.

Name some acute toxicity symptoms.

Dizziness, fainting, headache, nausea, vomiting.

Name some chronic toxicity symptoms.

Liver disease, brain disorders, cancer, infertility.

Why should regular examination gloves be avoided with chemicals?

They degrade quickly and can allow chemical to reach the skin.

What gloves should be used when working with dental chemicals?

Utility gloves.

What eye protection is recommended when handling chemicals?

Snug-fitting goggles for large chemical exposures; safety glasses if goggles are not used.

What protective clothing options are mentioned for chemical handling?

A lab jacket and neoprene or rubber aprons.

What does the SDS indicate about protective clothing?

It tells which protective clothing is ideal for a specific chemical.

What mask characteristics are recommended for inhalation protection with chemicals?

Fluid-resistant or fluid-repellent and provides respiratory protection.

What does the PPE recap require for chemical handling?

Protective clothing per SDS, a fluid-repellent mask, safety glasses or snug goggles, and utility gloves.

What is the purpose of planning for chemical spills?

To ensure safety and prevent hazards from spills.

What is the primary spill hazard in a dental office?

Mercury spills from amalgam.

What is a mercury spill kit used for?

Cleaning up mercury spills and preventing hazards to the dental team.

What safety device is required where chemicals are used?

An eye wash unit.

How should eye wash stations be maintained?

Flushed weekly for three minutes and inspected every three months.

Which areas require good ventilation when using chemicals?

Operatories, sterilization area, and any darkroom if used.

Where should dental chemicals be stored?

In a dry, cool, dark place, away from direct sunlight and excessive heat; follow manufacturer’s instructions.

What should you do with expired chemicals?

Dispose of them appropriately and rotate inventory; never use expired.

Why should you not fill an empty container with a different chemical?

Because certain chemicals react poorly together (e.g., bleach and ammonia).

What should you do with empty containers according to SDS?

Follow the SDS guidance for disposal of empty containers.

How does the EPA categorize dental waste?

As regulated vs non-regulated; hazardous waste is ignitable, corrosive, reactive, toxic, or EPA-listed.

What is general waste in a dental office?

Non-regulated waste discarded in regular covered containers.

What defines contaminated waste?

Waste that has come in contact with blood or bodily fluids.

What is infectious waste?

Contaminated waste capable of transmitting an infectious disease.

Can contaminated waste that is not infectious go in general trash?

Yes, if it is not infectious.

Where should infectious or regulated waste be placed?

In containers labeled with the universal biohazard symbol.

What are sharps containers used for?

Needles, blades, and anesthetic carpules; they are closeable, leak-proof, and puncture-resistant.

Where should the protector sheath for needles go?

In general waste.

What regulates hazardous waste while it is in the office vs after it leaves the office?

OSHA regulates in the office; EPA regulates after it leaves.

What determines disposal methods for infectious material?

The amount of infectious material.

What is a hazard communication program?

OSHA’s hazard communication standard (employee right to know) to inform employees about chemical identities and hazards.

What should employees understand under hazard communication?

Chemical symbols, hazard classification, labeling, and SDS information.

What is the SDS, in brief?

A 16-section document with health/safety info, properties, hazards, exposure routes, handling, first aid, spill control.

Where should SDSs be stored?

In a binder accessible to all employees.

What labeling requirements exist for chemical containers?

Containers must be labeled with required information; transferred containers must be labeled.

What does the NFPA diamond show?

Four colored diamonds with numeric ratings: blue health, red flammability, yellow reactivity, white special hazards.

Which items are exempt from NFPA labeling?

Tobacco, wood products, food, drugs, and cosmetics.

What regulations govern disposal of waste?

Federal, local, or state environmental regulations.

How should sharps be disposed after use?

In closeable, leak-proof, puncture-resistant containers.

What dictates disposal frequency for waste?

State regulations.

How should pharmaceutical waste be managed?

In a leak-proof container collected by a medical waste company.

Where should scrap amalgam be collected?

In a designated dry airtight container.

How should photochemical waste be handled?

According to regulations governing such waste.

What should be done with lead foil from traditional radiography?

Recycle it appropriately.

Can glutaraldehyde disinfectants be dumped down the drain?

Only if permitted by local authorities.

How should non-hazardous waste be managed?

Normally; recyclable materials should be recycled whenever possible.

What is sterilization as defined in the video notes?

A process intended to kill all microorganisms at the highest level, including spores.

How does disinfection differ from sterilization regarding spores?

Disinfection does not kill spores.

How many steps are involved in instrument processing according to the notes?

Seven steps.

What are the three classifications of instruments?

Critical, semi-critical, and non-critical.

What defines a critical instrument?

Instruments used to penetrate soft tissue or bone and have the greatest risk of transmitting infection; require heat sterilization.

Give examples of critical instruments.

Forceps, scalpels, bone chisels, and burrs that go in the handpiece.

What defines a semi-critical instrument?

Instruments that don’t penetrate soft tissue but touch mucous membranes or non-intact skin; may require heat sterilization or high-level disinfection.

If a semi-critical instrument is heat tolerant, what should be used?

Heat sterilization, just like critical instruments.

What defines a non-critical instrument?

Instruments that contact only intact skin and have a low risk of infection transmission; cleaned with EPA-registered intermediate or low-level disinfectant and do not need sterilization.

What is an example of a non-critical item?

A lead apron.

What is the general rule about heat-tolerant items?

If an item can be heat sterilized, it should be.

What PPE is required during sterilization procedures?

Jacket, mask, safety glasses, and puncture-resistant utility gloves; regular exam gloves are not sufficient.

Why are puncture-resistant gloves needed during sterilization procedures?

Because you will be handling sharp instruments and chemicals.

What should you use when transporting instruments to the sterilization area?

A transfer box to minimize handling and prevent percutaneous injuries and splashes.

Where should the instrument processing area be located and how should it relate to other spaces?

centrally located, dedicated to instrument processing, separated from operatories and labs, not part of a common walkway.

What are the two possible workflows for instrument processing?

Linear workflow (contaminated → packaging → sterilization → storage) or a U-shaped workflow.

What are the four basic areas of instrument processing?

Receiving and sorting, preparation and packaging, sterilization, and storage.

What is the purpose of signage in instrument processing?

To differentiate contaminated and clean areas.

What happens in the contaminated area?

Instruments are received, sorted, and pre-cleaned to remove debris and organic material; disposable items are discarded.

What happens in preparation and packaging?

Inspect cleaned instruments, place them in trays, and wrap or package them for sterilization; pre-cleaned instruments are not yet sterile.

Name pre-cleaning methods mentioned.

Holding solutions, ultrasonic cleaners, and instrument washing machines.

What is the purpose of holding solutions?

To prevent blood or debris from drying on instruments.

What do ultrasonic cleaners do?

Loosen and remove debris via cavitation and implosion.

Is hand scrubbing recommended?

No, due to injury risk.

How can you test ultrasonic cavitation effectiveness?

Use aluminum foil to check for even cavitation.

What can replace ultrasonic cleaners in some settings?

Automated washers or disinfectors approved by the FDA.

Why should metal instruments be dried thoroughly after steam sterilization?

To prevent rust; use rust inhibitors if needed.

What is the purpose of packaging after sterilization?

Keeps instruments sterile after sterilization and groups them into procedure sets.

What materials should be used for packaging?

FDA-approved packaging materials.

What is flash sterilization?

Sterilizing unwrapped items for immediate use in emergencies.

What does sterilization destroy?

All microbial forms, including spores.

What are the common heat sterilization methods?

Steam, chemical vapor, and dry heat.

How does a steam autoclave work?

Sterilizes using steam under pressure with four cycles: heat up, sterilize, depressurize, and dry.

What is unsaturated chemical vapor sterilization?

Uses chemicals to create vapor (e.g., alcohol, formaldehyde, ketone, acetone, water).

What are the advantages of chemical vapor sterilization?

No rust, short cycle, fast drying.

What are the disadvantages of chemical vapor sterilization?

Chemical odor, need for ventilation, formaldehyde monitoring.

How is packaging for chemical vapor sterilizers described?

Similar to steam sterilizers.

What is dry heat sterilization and how does it differ from steam?

Transfers heat from air to instruments; reaches higher temperatures and prevents rust if instruments are dry.

What are the two types of dry heat sterilization?

Static air and forced air.

What is ethylene oxide sterilization used for and its typical duration?

Low-temperature sterilization suitable for plastics and rubber; takes 4–12 hours.

What are liquid chemical sterilants used for?

Sterilants for heat-sensitive items.

What are common causes of sterilization failures?

Incorrect time, improper cleaning, packaging errors, or sterilizer malfunctions.

What are the three monitoring categories for sterilization?

Physical, chemical, and biological monitoring.

What is physical monitoring?

Checking machine readouts for time, pressure, and temperature.

What is chemical monitoring?

Indicators outside the package (temperature parameter) and integrators inside the package (pressure, temperature, time).

What is biological monitoring?

Spore testing at least weekly to ensure sterilizers kill spores.

What type of instruments are handpieces classified as?

Semi-critical instruments.

Do handpieces penetrate tissue?

No, but the attached burr does.

What is the sterilization temperature requirement for handpieces?

Below 275°F.

What special step should be taken with handpieces before sterilization?

Flush debris using a handpiece lubricator before sterilization.