3.4 Infection Control, Personal Protective Equipment (PPE), and Safety Data Sheets (SDS)

3.4 Infection Control, Personal Protective Equipment (PPE), and Safety Data Sheets (SDS)

Hospital environments are breeding grounds for infectious pathogens. Biomedical equipment technicians (BMETs) frequently work inside patient care units, surgical suites, and laboratory settings, and they handle equipment that has been in direct contact with patients. Consequently, BMETs must follow strict clinical infection control procedures to protect themselves, their colleagues, and subsequent patients from healthcare-associated infections (HAIs). Additionally, technicians must handle hazardous chemicals safely, guided by standard communication sheets and proper material classification.

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Universal Precautions and Hand Hygiene

The foundational concept of clinical infection control is Universal Precautions (often combined with Standard Precautions). Under these guidelines, all human blood, body fluids, secretions, excretions (except sweat), non-intact skin, and mucous membranes must be treated as if they are infectious, regardless of the patient's diagnosed status. Pathogens of primary concern include Bloodborne Pathogens like Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV), and Hepatitis C Virus (HCV).

Hand Hygiene

Hand hygiene is the single most effective way to prevent the spread of infections.

• Alcohol-Based Rubs: Can be used for routine hand hygiene if hands are not visibly soiled.
• Soap and Water: Must be used when hands are visibly dirty or contaminated with proteinaceous material, blood, or other body fluids. It is also mandatory after caring for patients with suspected or confirmed spore-forming pathogens, such as Clostridioides difficile (C. diff) or anthrax, because alcohol is ineffective at destroying bacterial spores; they must be physically washed off the skin.

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Personal Protective Equipment (PPE)

Personal Protective Equipment (PPE) acts as a barrier between the technician and infectious materials or hazardous chemicals. The selection of PPE is determined by the nature of the task and the anticipated level of exposure.

Types of PPE:

• Gloves: Protect hands. Nitrile gloves are preferred over latex in healthcare due to common latex allergies.
• Gowns: Protect clothing and skin from splashes of body fluids or chemical agents.
• Masks and Eye Protection: Surgical masks protect the nose and mouth from splashes or large droplets. Goggles or face shields protect the mucous membranes of the eyes.
• Respirators (N95 or PAPR): Used when entering rooms of patients under airborne precautions (e.g., Tuberculosis, Measles, Varicella). These devices filter out at least 95% of airborne particles.

Donning and Doffing Sequences

To prevent self-contamination, PPE must be put on (donned) and taken off (doffed) in a specific, standardized order:

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Chemical Safety and Safety Data Sheets (SDS)

BMETs frequently use hazardous chemicals, including lubricants, cleaning solvents, adhesives, and sterilizing agents (such as glutaraldehyde or ethylene oxide). OSHA's Hazard Communication Standard (HCS) requires manufacturers to provide a Safety Data Sheet (SDS) for every hazardous chemical.

An SDS is organized into 16 standardized sections under the Globally Harmonized System (GHS) of Classification and Labeling of Chemicals. BMETs should be familiar with the layout, especially the following key sections:

• Section 1: Identification: Product name, manufacturer contact info, and recommended uses.
• Section 2: Hazard(s) Identification: Details the chemical's hazards using GHS pictograms, signal words ('Danger' for severe hazards, 'Warning' for less severe), and precautionary statements.
• Section 4: First-Aid Measures: Describes the initial care that should be given by untrained responders if exposure occurs (e.g., 'flush eyes with water for 15 minutes,' 'move to fresh air').
• Section 7: Handling and Storage: Safe handling practices and storage requirements (e.g., ventilation, temperature, incompatible chemicals).
• Section 8: Exposure Controls/Personal Protection: Lists OSHA Permissible Exposure Limits (PELs) and the specific PPE (such as chemical-resistant gloves or respirators) required to handle the chemical safely.
• Section 10: Stability and Reactivity: Chemical stability information and conditions to avoid (e.g., mixing bleach with ammonia, which produces toxic chloramine gas).

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Cleaning, Disinfection, and Sterilization

Infection control requires processing medical equipment between patient uses. The Spaulding classification system divides medical devices into three categories based on the risk of infection, determining whether a device requires cleaning, disinfection, or sterilization:

Methods of Sterilization:

• Steam Sterilization (Autoclaving): The most common, reliable, and cost-effective method. It uses saturated steam under pressure. Standard cycle parameters are typically 121°C (250°F) at 15 psi for 15 to 30 minutes, or 132°C (270°F) at 27 psi for 4 to 10 minutes.
• Ethylene Oxide (EtO) Gas: Used for heat- and moisture-sensitive devices. EtO is highly effective but is a known carcinogen and mutagen, requiring long aeration times (often 8–12 hours) to safely dissipate residual gas.
• Hydrogen Peroxide Gas Plasma: A low-temperature sterilization method for heat-sensitive items. It is faster than EtO and leaves no toxic residue, as it breaks down into water vapor and oxygen.