Laboratories require controllable air quality with sufficient ventilation, temperature and humidity levels. Variations in the atmosphere within a laboratory can measurably affect the results of certain functions and compromise human health. Because of the technical nature of laboratory environments, only qualified HVAC technicians should be involved on the design and installation of highly sensitive systems.
Sufficient ventilation and a specific number of air changes are fundamental. The presence, use and storage of potentially harmful chemicals can require a minimum number of air changes per hour plus extensive filtering and evacuation capability.
For safety, HVAC services for laboratories should be specific and uncompromising. When you choose General Mechanical, you are assured that you’re getting the most experienced, knowledgeable and well-trained technicians in the Chicagoland area.
Contact us today to get started on the proper air conditioning and ventilation for your Chicagoland laboratory.
Ventilation for Laboratories
Ventilation determines the degree of exposure to harmful emissions. Less ventilation equals higher levels of exposure and potential danger from chemicals and contaminants. In designing or retrofitting a laboratory, close attention must be given to the types of materials that will be used and areas to be ventilated.
American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) members work with Mechanical Engineers to design operational functions of HVAC systems. When designing HVAC services for laboratories, our engineer examines fume containment, filtration, air changes per hour, methods of capturing fumes, plus temperature and humidity requirements.
Specific code requirements outline procedures for managing hazardous materials, chemicals and contaminants. General Mechanical experts can review proper procedures.
Chicago, IL Laboratory Ventilation Services
Improperly ventilated laboratories can be dangerous places. Chemical and biological laboratories routinely handle volatile chemicals, compounds, and mixtures that, under the wrong conditions, can accumulate harmful gas, react violently, or create other risks to humans.
Control is the essential element in a laboratory. Maintaining predetermined ventilation levels plus proper temperatures and humidity levels are fundamental safeguards to laboratory management safety. The primary measure of ventilation for these situations is ACH or air changes per hour. This standard metric defines the rate at which ambient air is flowing through the room and depends on the size of the laboratory and the manner in which the air is evacuated. Strategically placed fume hoods play a role in eliminating harmful airborne chemicals.
The degree of risk in any lab depends upon the materials that will be handled. According to a University of Washington study, “Determination of Laboratory Airflow Rates,” some chemicals require higher ACH under normal conditions. Chemicals such as chlorine and other poisonous gas must be removed quickly to prevent harm to the occupants.
Different HVAC Equipment for Different Types of Laboratories
ASHRAE defines four general classifications of laboratories as:
- Biological Labs: Engaged in biological, pharmacology and microbiological study.
- Chemical Labs: Designed for the study of organic and inorganic materials.
- Animal Labs: Study laboratory animals for observation and testing.
- Physical Labs: Conduct physics experiments that involve analytical equipment, optics, laser usage and a wide range of other types of experiments.
Each category has applicable standards for ventilation and air quality. Minimum standards in breathing zones and air have been established.
No matter which laboratory you have, you can trust that General Mechanical is up to date and experts on all of these standards.
HVAC Standards for Laboratories in Chicagoland & the U.S.
There are several codes, guidelines and standards for various laboratory situations to ensure the health and safety of workers. In addition to ASHRAE standards, the International Building Code (IBC) provides guidelines for lab air quality. The International Mechanical Code also defines ventilation rates and exhaust system requirements for scientific laboratories.
OSHA (Occupational Safety and Health Administration) has set general guidelines for laboratory best practices. General Mechanical is the top industrial HVAC provider in Chicagoland that is completely qualified to install HVAC systems for lab air quality.
Defining Air Quality
Four classes of air quality define the robustness of the HVAC systems and how potentially hazardous air should be recirculated. The categories are:
- Class 1: Contains very low contaminant content and may be reused without harm.
- Class 2: Contains moderate contaminants and odors that may be recirculated, though not into areas classified as Class 1.
- Class 3: Contains considerable contaminant and sensory irritation qualities. This air can be recirculated only within the area where it is generated, but to no other space.
- Class 4: Contains highly contaminant fumes, gases and particles. This air must be contained and not circulated to any other space. A Class 4 fume hood is designed to divert discharge away from air intakes and open windows.
One ACH Standard May Not Fit All
The configuration of the air flow system and rate of air changes per hour (ACH) within a chemical laboratory depends upon the materials that are present. For many commonly used chemicals, 10 ACH per hour is sufficient for safety.
However, unexpected spills and leaks or the most harmful chemicals may not be mitigated easily by increasing ACH, in which case a clearly defined evacuation route may be necessary to protect the occupants.
The Lab Ventilation ACH Rate Standards and Guidelines of January 2012, explicitly sets required levels and procedures mandated by ASHRAE and other global entities to determine safety in the laboratory. The associations contributing guidelines are:
- U.S. National Fire Prevention Association (NFPA) Standard 45
- Occupation Safety and health Administration (OSHA) Regulations
- ANSI/AIHA Z9.5 Lab Ventilation Standards
- ACGIH Industrial Ventilation Manual
- ASHRAE 62.1 Standard for Ventilation for Acceptable Indoor Air Quality
- European Ventilation Code
ASHRAE has come closest to establishing the appropriate standards for chemical laboratories. A level of 6-12 air changes per hour and a relative humidity less than 65% have been the accepted norms, rates that depend upon the materials used, evaporation rates, the quantity of chemical released, and even the size of the room.
Typical HVAC Equipment for Laboratories
HVAC for laboratories utilizes several dedicated types of equipment for safety.
Fume hoods are designed to evacuate fumes and unwanted gases from the area. Types of fume hoods include 1) standard, 2) bypass hoods that provide continual air evacuation, 3) variable volume hoods that increase or decrease air flow, and 4) auxiliary fume hoods that can serve as back-ups.
Role of Fume Hoods & Sensors
Most recent guidelines, however, have determined that dilution factor by a particular ACH rate alone does not ensure complete safety in an active lab. Rather, the containment force of a correctly positioned fume hood provides more rapid evacuations of dangerous airborne chemicals.
Sensors may also play a significant role in managing airflow. Energy can be saved maintaining a reduced ACH level, but accelerate to predetermined levels when potentially harmful airborne chemicals are detected.
Contact the Experts at General Mechanical
During the design phase or retrofit of a chemical laboratory, HVAC experts should be included. Proper positioning of hoods, sufficiently robust airflow systems, and carefully developed evacuation plans are essential to the safety of the occupants. General Mechanical has decades of experience in designing, installing, and maintaining effective HVAC systems for laboratories and other uses. Our expertise and industry knowledge can protect your laboratory workers from harmful chemicals.
For HVAC services for laboratories in Chicagoland, contact the qualified HVAC experts at General Mechanical.