ED&G 100 Design Project

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EDG 100 Design Project

• Fume Hood Face
• Velocity Control
• Spring 2004

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Tonights Agenda

• Functionality of a fume hood
• Types of fume hoods
• Laboratory Room Airflow Control
• Fume hood face velocity calculation
• Fume hood testing methods
• Safety Concerns
• Design Project Recap
• Questions

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Fume Hoods

• What is a fume hood?
• How does a fume hood work?

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Some Common Types of Fume Hoods
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Laboratory Room Control
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Fume Hood Control
Constant Air Volume Fume Hood
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Fume Hood Control

• Variable Air Volume Fume Hood

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Fume Hood Control
Fume Hood Cost Savings Example

• 6 foot wide fume hood
• 1250 CFM maximum exhaust airflow
• Cost to operate
• Constant Volume Hood - 3750 - 6250
• Variable Volume Hood - 1500 - 2500

9
Components of a Bench Top Fume Hood
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Fume Hood Sash

• What is a sash?
• What are the different configurations for the
  sash?
• What happens when a sash is moved?

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Fume Hood Face Velocity

• What is face velocity?
• How is face velocity calculated?

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Average Value for Face Velocity

• What is the average value for face velocity?
• What happens if the face velocity is above or
  below 100 (ft/min)?

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Average Face Velocity Recommendations

• ACGIH
• NIOSH
• ANSI (Standard Z9.5-1992)
• NFPA
• OSHA
• NIH
• SEFA

• 80 to 100 fpm
• 100 to 150 fpm
• 80 to 120 fpm
• 80 to 120 fpm
• 60 to 100 fpm
• 100 fpm
• 100 fpm

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Fume Hood Testing ASHRAE 110 Standard

• Measurements of Face Velocity
• Air Flow Visualization Test (Smoke Test)
• Tracer Gas Containment Test

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Measurements of Face Velocity
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Airflow Visualization Test (Smoke Test)
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Tracer Gas Containment Test
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Tracer Gas Test - Video Simulation
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Laboratory Safety Concerns

• Fume hoods are the primary protection of the lab
  occupant
• Labs can contain biomedical wastes, toxic or
  hazardous chemicals, explosive substances,
  radioactive isotopes, etc.

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Some Safety Guidelines and Regulations

• ANSI/AIHA Z9.5, Laboratory Ventilation
• OSHA Laboratory Standard 29CFR 1910.1450
• NFPA 45
• ASHRAE TC 9-10
• Public Works Canada MD 15128
• FDA Validation Protocols
• Local Building Codes

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Visual Fume Hood Reminders
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Design Project Recap

• Goal Design a method for calculating the open
  fume hood face area (sash opening) and
  maintaining a safe face air velocity at all times
  and with all sash positions.
• Critical Design Requirements
• A materials cost goal lt2000.
• Adaptable for various fume hood and sash
  configurations.
• Must be maintenance-friendly must be able to
  access equipment for preventative care, problems,
  etc.
• Must be able to be installed in less than 45-55
  minutes.
• Must not interfere in any way with the day-to-day
  operations of the fume hood user.
• Must be stable, repeatable, and accurate to be
  able to be used at FDA-regulated sites (e.g.
  pharmaceuticals, etc.)
• Must not contribute to overall laboratory noise
  (both from the fume hood exhaust airflow control
  system and the fume hood sash sensing system).

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Questions?

• Good luck on your design projects!