303: Local Exhaust Systems
Safety Policy & Procedure Manual
Section 300: Laboratory Safety
To ensure a safe and healthy work environment by establishing guidelines for exhaust systems.
Oregon State University requires the use of adequate local exhaust systems when required by federal, state, and local regulations pertaining to human exposures to hazardous materials in the air.
Environmental Health & Safety (EH&S) and Radiation Safety (RS)
Environmental Health and Safety is responsible for establishing and facilitating a program covering local exhaust inspection, approval, and posting, in compliance with applicable policies, rules and regulations. Radiation Safety is responsible for assessment and monitoring compliance for exhaust systems where radioactive materials are used or stored.
Supervisor and Employee Responsibility
All persons conducting work or storing hazardous materials in a local exhaust system shall ensure compliance with all postings and will use the system only as designed and for which it is approved.
- Each local exhaust system used to control the exposure of humans to hazardous chemicals or other detrimental materials in the air must be approved by Environmental Health and Safety (EH&S). If radioactive materials are to be involved, approval by Radiation Safety (RS) is also required. Local exhaust systems include chemical fume hoods, biological safety cabinets, close capture vents, glove boxes, and similar devices, but not building ventilation systems or other multi-area systems.
- Any concerns regarding the need for a local exhaust system for control of human exposure to radioactive materials shall be sent to and resolved by RS, and EH&S for exposures to other materials.
- For new systems, approval requires the following:
- The system must be of a design suitable for its intended use (i.e., suitable dimensions, no use of chemical fume hood where glove box is needed, suitable location, etc.).
- The system shall be easily decontaminated (i.e., smooth surfaces, non-absorbent and non-reactive with respect to intended materials to be contained, surfaces reasonably accessible, etc.).
- The system shall provide a reasonably uniform airflow rate, of suitable velocity, to capture or control the hazardous materials present under all expected working conditions.
- Chemical fume hoods to be used with regulated carcinogens must have minimum average face velocity of 150 linear feet per minute (lfm), with no point less than 120 lfm, for any working opening.
- Chemical fume hoods to be used for radioactive materials and other hazardous material, but no regulated carcinogens, must have minimum average face velocity of 100 lfm, with no point less than 80 lfm, for any working opening.
- Minimum sash height for chemical fume hoods will be fifteen inches except where otherwise approved by EH&S.
- For biological safety cabinets, close capture hoods, etc., EH&S shall approve minimum face velocity and opening size on a case-by-case basis. Where applicable, EH&S will specify maximum face velocity and/or minimum sash opening.
- For existing systems that do not meet the requirements for a new system, EH&S may approve variances provided that adequate safety is insured. Any such variance must be documented, with a copy sent to the using department.
- Any content or use restrictions will be posted conspicuously on each local exhaust system. For vertical sash fume hoods, minimum sash height will be posted. Filter change needs, power switching needs, requirements for physical entry into or work on the system, etc., shall be posted if requested by EH&S or RS.
- Systems having substandard airflow rates may be used only for storage, and not for active work with hazardous chemicals. Such systems will be conspicuously posted "For Storage Only" and approved by EH&S. Any restrictions on permissible materials for storage will be prescribed by EH&S and conspicuously posted.
- For each local exhaust system, a routine inspection program will be conducted by EH&S or persons approved by EH&S. A report of each inspection shall be given to the operating department, with a copy retained by EH&S. The report shall include recommendations for any needed corrective actions.
- The operating department will insure that each required local exhaust system is properly maintained and not misused.
Environmental Health & Safety (EH&S) - (541) 737-2273
Radiation Safety (RS) - (541) 737-2227