Basic Documentation

Page 4 of 10 Siemens Industry, Inc.
Document No. 149-980
Table 1. Recommended Ventilation System Types for Various Chemistry Laboratory Applications.
Type of Facility Laboratory Function Usage Pattern Ventilation System
Recommendation
1. Small Testing and
Analysis Facility:
Private laboratory or a
small laboratory within a
medical or commercial
enterprise.
Provides testing and
analytical services for
environmental, medical,
and other specialty
purposes.
Mainly involves repetitive
testing in a prescribed
manner. No research or
experimentation is
conducted. Work is
performed during routine
workday hours.
CAV 1-Position Possibly with
a fume hood exhaust shut-
down provision
4
CAV (2-Position)
2. Small College:
Undergraduate
Chemistry Teaching
Laboratory
Provides basic chemistry
instruction. No highly
toxic or dangerous
chemicals are present.
Rigidly scheduled usage
periods. The lab may not be
utilized for extended periods
such as a summer
semester.
CAV 2-Position
CAV 1-Position with a fume
hood exhaust shut-down
provision
4
3. Large College or
University:
Large Undergraduate
and Graduate Chemistry
Teaching Laboratories
Provides basic and
higher level chemistry
instruction. Limited use
of toxic or dangerous
chemicals.
Rigidly scheduled usage
periods. Some labs may not
be use for summer
semesters.
CAV 2-Position
Possibly with a fume hood
exhaust shut-down provision
4
VAV
4. University Research
Laboratories
High-level research by
esteemed researchers
and graduate students.
Does not follow a specific
usage schedule. Occupancy
and use ranges from
intensive to sporadic and on
any day and time.
VAV
LAF
5. Government Agencies:
 Crime Laboratories
 Regulatory Agencies
Conducts testing and
analytical services on
evidence and for
regulatory compliance
purposes.
Most testing is done in a
prescribed manner with no
research of experimentation.
Work is performed during a
routine business day.
CAV -2-Position
VAV
LAF - 2-Position
6. Government Research
 High Tech Defense
 Space Research
Advanced research
under high security
conditions. Research
conducted by top-level
scientists.
Labs generally occupied
according to a regular
schedule but schedule
variations frequently occur.
VAV
LAF - 2-Position
7. Small/Mid-Size
Commercial and
Industrial Firms
Quality control and
product development
testing and research.
Labs generally occupied
according to a set schedule,
but schedule variations can
occasionally occur.
CAV -2-Position
LAF - 2-Position
8. Large Commercial and
Industrial Firms
Various levels of testing,
product development and
research for a wide array
of purposes.
Labs generally occupied
according to a set schedule,
but frequent variations are
likely.
VAV
LAF - 2-Position
4
NFPA 45 states: "The hood shall provide containment of the possible hazards and protection for personnel at all times when chemicals
are present in the hood." Thus, if all chemicals are removed from a fume hood its exhaust system is not required to remain operating.
Unless the fume hood exhaust system is also required to maintain the required laboratory room ventilation rate and negative
pressurization, the fume hood exhaust system could be shut down when the laboratory room is unoccupied.