9. Environmental Transmission Flashcards
Risk from equipment and the environment (4)
High risk (critical) Medium risk (semi-critical) Low risk (non-critical) Minimal risk
Definition of high risk equipment
Items in contact with normally sterile body sites
Definition of medium risk equipment
Items in contact with intact mucous membranes
Definition of low risk equipment (2)
Items in contact with intact skin
Cleaned/chemically disinfected
Definition of minimal risk equipment (2)
Items not normally in contact with intact skin
Cleaned (chemically disinfected in risk assessed circumstances)
Types of non-critical environmental surfaces (2)
Housekeeping surfaces
Clinical contact surfaces
Features of housekeeping surfaces (2)
Not directly touched during dental treatment
Carry the lowest risk of disease transmission
Features of clinical contact surfaces (2)
Contaminated from patient materials either by direct spray or spatter generated during dental procedures
Contaminated by contact with gloved hand of dental healthcare professional
Influenza surface survival time (2)
Steel/plastic - 24-48hrs
Cloth, paper tissue - 8-12hrs
Influenza transmission (3)
Steel to hands over 24hrs
Paper tissue to hands for 15mins
Viruses survives 5mins on hands
Breaking the chain of infection from surfaces - reservoir
Surface design, surface material, cleaning, preventing recontamination, disinfectant/detergent
Breaking the chain of infection from surfaces - portal of exit
Aerosol control
Breaking the chain of infection from surfaces - mode of transmission
Hands, fomites
Breaking the chain of infection from surfaces - portal of entry
PPE
Breaking the chain of infection from surfaces - susceptible host
Vaccinations
Common issues with surface cleaning (3)
Body fluid forms surface films (facilitates pathogen attachment)
Visual assessment of cleanliness (poor measure of invisible soiling)
Cleaning process - potential to re-contaminate surfaces
Definition of detergent (2)
Group of synthetic organic water-soluble agents
Have wetting agent, emulsifying and soil holding properties
Definition of disinfection
Process for the removal or destruction of microbes not usually including bacterial spores
Features of high-level disinfectants
Kill all microbes (including mycobacteria) but not large numbers of bacterial spores
Usually require long contact time (hrs)
Features of low-level disinfectants
Kill most vegetative bacteria, some fungi and some viruses
Practical period of time (<10mins)
Portal of exit - aerosol control (2)
High volume aspiration
Rubber dam
Portal of entry
PPE
Definition of cleaning
Physical removal of contamination
