Basic Documentation
Table Of Contents
- About this Application Guide
- Chapter 1–Introduction
- Chapter 2–Goals of the Laboratory Environment
- Chapter 3–Unique Ventilation Needs of a Laboratory Facility
- Chapter 4–Ventilation Systems Classification
- Chapter 5–Laboratory Facility Exhaust Systems
- Chapter 6–Laboratory Containment Units - Ventilation
- Chapter 7–Room Ventilation, Makeup Air, and Pressurization Control Systems
- Chapter 8–Laboratory Temperature and Humidity Control Systems
- Chapter 9–Laboratory Emergencies - Ventilation System Response
- Chapter 10–Laboratory Ventilation System - Validation
- Chapter 11–Laboratory Ventilation System - Commissioning
- Glossary
- Index
Occupant Comfort Versus Occupant Safety
TYPE OF
ROOM
Hospita
l Patient
Room
Protective
Isolation
Rooms
Infectious
Isolation
Rooms
Biochemistry
Lab
Animal
Lab
Autopsy
Lab
Chemical
Storage
Room
ACH RATE
4 15 6 6 to 10 10 to 15 12 6
OUTSIDE AIR
TO ACH
RATE
1/3 1/3 1/3 1/3 100% 1/6 1/3
Process Ambient Requirements
An experiment or process may require specific room ambient conditions that must be
maintained. If so, then this also becomes a required goal of the laboratory ventilation system.
Most laboratory room procedures and processes do not pose requirements that are
unacceptable in terms of human comfort. For instance, although animal laboratories
generally require maintaining specific relative humidities and temperatures along with higher
air movement rates, these requirements generally do not pose an unacceptable comfort level
for humans who must spend some time in these rooms. However, if the required ambient
conditions (for example, very low temperatures) pose a significant discomfort level to persons
who need to be present, it may become necessary to isolate and condition the process
environment apart from the overall laboratory room.
All requirements for specific process ambient requirements must be made known to the
designers and planners as soon as possible and certainly well before a project design is
finalized. HVAC system designs that are only required to maintain human comfort may not be
able to maintain ambient conditions that are significantly different from that normally provided
for human comfort. To ensure the HVAC systems can provide special ambient conditions, the
HVAC designers and planners may need to incorporate specialized equipment or special
design approaches to ensure such requirements will be met. Circumstances where process
ambient requirements present a substantial conflict with personnel comfort will also need to
be addressed, possibly by incorporating special physical partitioning in the laboratory room or
other measures in conjunction with the room design.
Occupant Comfort Versus Occupant Safety
A laboratory environment should provide a high level of occupant comfort to maximize their
productivity and concentration. A room environment that is not comfortable will entice the
occupants to institute various measures of their own that could significantly compromise the
health and safety of the environment. For instance, using a portable fan in a laboratory room
that is too warm would likely upset ventilation air patterns that are specifically intended to
keep airborne contaminants away from occupants. Similarly, adding portable heating
appliances could create a dangerous situation if flammable or explosive substances are
present in the room. Likewise, a room with too low of a relative humidity level would pose a
hazard since static electricity discharges might occur in proximity to flammable liquids or
gasses.
Siemens Building Technologies, Inc. 7