Fume Hood

Fume Hood

A fume hood is a type of ventilation system designed to limit exposure to hazardous or toxic fumes, vapors, and dusts in laboratory settings. It functions as a critical safety device by containing and exhausting harmful substances, thereby protecting the user and the environment.

Key Components and Functions:
  1. Work Surface: The area inside the fume hood where experiments or procedures are conducted.
  2. Sash: A movable glass window that can be raised or lowered to open or close the front of the hood, allowing access to the workspace while still providing a barrier.
  3. Exhaust System: A fan and ductwork that pull air from inside the hood, filter it (if needed), and expel it outside the building.
  4. Airflow: The fume hood draws air away from the user and into the hood, reducing the risk of inhalation of hazardous substances.

Types of Fume Hoods:
  • Ducted Fume Hoods: These are connected to an external exhaust system and are typically used for applications that involve volatile chemicals.
  • Ductless Fume Hoods: These filter the air and recirculate it back into the laboratory, and are suitable for less hazardous materials.

Applications:
Fume hoods are commonly used in laboratories that handle chemicals, biological materials, or radioactive substances. They are essential for ensuring safe working conditions when dealing with volatile or hazardous materials.

Regular Inspection.
Regular inspection of a fume hood is essential to ensure its proper functioning and safety. Inspections help identify any issues that could compromise the fume hood's ability to protect users from hazardous substances.

Key Reasons for Fume Hood Inspections:
  1. Safety Compliance: Ensures the fume hood meets safety standards and regulations.
  2. Proper Functionality: Verifies that the hood is effectively containing and exhausting hazardous fumes, vapors, and dust.
  3. Airflow Verification: Confirms that the airflow is sufficient to pull contaminants away from the user and out of the laboratory.
  4. Preventative Maintenance: Identifies any wear and tear or potential malfunctions before they become serious issues.
  5. User Safety: Protects laboratory personnel by ensuring the hood is providing the necessary level of protection.
 
Common Inspection Checks:
  • Airflow Measurements: Using an anemometer or similar device to measure the face velocity of air entering the fume hood.
  • Sash Inspection: Checking the sash for smooth operation and that it remains in place at any height.
  • Physical Condition: Inspecting the structure, including seals, glass, and ductwork, for any damage or wear.
  • Filter Status: If it’s a ductless fume hood, the filters need to be checked and replaced if saturated.
  • Alarm and Indicator Checks: Ensuring that alarms and indicator lights (if equipped) are functioning correctly.
 
Inspection Frequency:
  • Annual Inspection: Usually required for compliance with safety regulations.
  • Routine Checks: Users should perform basic checks each time the fume hood is used, such as ensuring airflow and sash positioning.
Regular inspections are vital for maintaining the effectiveness of fume hoods and ensuring a safe laboratory environment.