USP 797 is a standard for sterility that pharmaceutical compounding and preparation facilities must demonstrate. USP 797 is set by the United States Pharmacopeia and National Formulary (USP-NF) and ensures patient safety by protecting pharmaceuticals from contamination during preparation. Following USP 797 reduces infection, contamination, and improper dosage to maintain superior quality products in facilities such as pharmacies, operating rooms, chemotherapy units, hospital pharmacies, and nuclear pharmacies.
Meeting USP 797 Environmental Quality & Control Requirements
Meeting USP 797 standards is critical to the safety of pharmacy environments, as it ensures clean and sterile conditions for compounding and preparing pharmaceutical products. Sterile compounding pharmacy environments and other cleanrooms can demonstrate compliance by following USP 797 standards for monitoring and controlling airborne particles. It is necessary to follow USP 797 to comply with FDA and local regulations, protect against liability, and remain competitive.
USP 797 provides guidelines for the following:
ACPH. Hazardous drug (HD) storage rooms require at least 12 air changes per hour (ACPH) for refrigerated, sterile, and nonsterile storage. Buffer rooms and anterooms with access to HDs require 30 ACPH, and anterooms without HD access require 20 ACPH. Buffer rooms with a redundant HEPA filtration system require 12 ACPH.
Temperature. Cleanroom temperatures are dependent on the comfort of personnel. It can change relative to the necessary gowning or personal protective equipment (PPE). Sweat and shivering result in more particulate shedding by personnel, so temperatures must not be too low or too high. Uncomfortable temperatures can also encourage staff to shed gowning to cool down or wear unauthorized clothing for warmth.
Humidity. Clean rooms must maintain an adequate humidity level to prevent personnel from sweating due to high humidity and static buildup in low humidity. Low humidity can also cause residual adhesives from labels to stick to surfaces like gloves. According to USP 797, relative humidity (RH) must be below 60% at all times.
Pressure. Non-HD compounding pharmacies must maintain positive air pressure to keep airborne particulates, contaminants, and dirt from entering through doors, crevices, and ceiling tiles from outside the cleanroom. HD compounding pharmacies require a negative pressure buffer and positive pressure anteroom to prevent contamination and control HD particles.
Air quality. Maintaining quality standards requires monitoring of airborne particles. Viable particles require monitoring every week, and non-viable particles require monitoring every six months.
Why Your Central HVAC System Won’t Help You Meet USP 797
Sterile compounding pharmacies within confined spaces often become a hotspot when using a standard building air conditioner that cannot keep up with the humidity. Relying on a standard HVAC system can often times result in a space above USP 797 humidity requirements. Maintaining USP 797 compliance requires an HVAC system designed for pharmaceutical applications. Air Innovations offers HVAC solutions to maintain USP 797 compliance.
Air Innovations HVAC Solutions
The HEPAir® Cleanroom HVAC Unit by Air Innovations is the ideal solution to maintaining USP 797 humidity, temperature, pressure, and air quality standards for sterile compounding pharmacies. The HEPAir unit operates independently of the building HVAC system, only serving isolation areas such as cleanrooms, pharmacies, and laboratories. Facilities can also implement several HEPAir units to provide additional air quality and climate control where necessary.
Contact Us for Environmental Control Solutions for Your Compounding Facility
Maintaining USP 797 requirements in your sterile compounding pharmacy space is crucial in delivering a safe product. Rely on Air Innovations’ HEPAir Cleanroom HVAC Unit to ensure USP 797 compliance. As a leader in designing and manufacturing environmental control solutions, we have the necessary knowledge and experience to deliver quality systems to help you abide by critical industry standards. For more information about our HEPAir Cleanroom HVAC Unit or other environmental control solutions, contact us today.
Negative or positive pressure rooms are often necessary to prevent contamination and maintain a climate-controlled environment in various applications. While these rooms are somewhat similar, there are certain differences between their designs and requirements. Here we’ll give an overview of both of these types of environments, including their intended applications and design requirements.
Negative Pressure RoomPositive Pressure Room
Negative Pressure Rooms
Negative pressure rooms have air pressure that is lower than the external air pressure. Negative pressure is achieved through the use of an exhaust system that frequently includes a high-efficiency particulate air (HEPA) filter connected to a sealed room. These rooms can trap potentially dangerous particles to prevent cross-contamination in external air. This is why they’re often used to isolate infected patients while keeping people outside of the room consistently safe.
Design Requirements
Negative pressure rooms are designed to contain airborne infections. To do so, there are various design requirements that these rooms must follow, which are outlined by CDC Guidelines, ASHRAE standards, and Healthcare Design Construction Guidelines. As summarized in these guidelines:
Negative pressure rooms must undergo at least 12 total room air changes every hour.
They need to maintain a negative pressure differential of at least 0.01’’.
Exhaust from these rooms and any connected anterooms or toilet rooms needs to travel directly outdoors with no chance of contaminating exhaust from other spaces.
If an anteroom is included in the setup, airflow needs to travel into the anteroom via the corridor. From there, it should be channeled into the patient isolation room.
The quantity of air exhaust needs to be higher than the supply airflow to maintain a consistent pressure differential.
The exhaust grille must be located in the ceiling and near the head of the bed.
All exhaust air must be discharged through a HEPA filter if the fan is below the roof line.
Misconceptions About Negative Pressure Rooms
One potentially dangerous misconception about negative pressure rooms is that medical personnel are safer when performing aerosol-generating procedures on patients in these rooms. This is due to the Centers for Disease Control and Prevention (CDC) recommendation that these procedures be performed in isolation rooms. However, negative pressure rooms do little to protect individuals inside the room. Their main purpose is to help protect people outside of the room by keeping aerosols and other particles within the room.
Positive Pressure Rooms
A positive pressure room is intended to protect patients from infectious diseases if they’re immunocompromised. While this type of room is somewhat similar in concept to negative pressure rooms, it features certain differences in its function and design. Positive pressure rooms contain a higher pressure in the containment area than the external environment, preventing air from leaving the room and circulating back inside. This prevents occupants in the room from being exposed to any outside contaminants, including potentially harmful particles and germs.
Design Requirements
Positive pressure rooms must follow various design requirements to keep patients protected from outside contaminants. Included in these requirements are the following elements:
Positive pressure rooms require at least 12 air changes every hour.
They must maintain a minimum positive pressure differential of 0.01’’.
If anterooms are used, the airflow must travel to the anteroom from the patient room and then into the adjacent corridor.
Normally, a 150 to 200 CFM airflow difference is sufficient for maintaining the ideal pressure differential in these rooms.
HEPA filters are required to supply clean air. These filters are normally located at the room’s supply terminals or the main air-handling unit.
Airflow to the room needs to stay at a constant volume for consistent ventilation.
Create Custom Positive and Negative Pressure Environments with Air Innovations
If you require flexible positive or negative pressure rooms for your application, Air Innovations has the expertise and solutions you need. Our IsolationAir® unit offers a portable contamination control system that can efficiently convert standard-sized patient rooms into either positive or negative pressure environments. Some of the features of our IsolationAir® system include ductwork, UV sterilization, and HEPA filtration connections. The system also allows for temperature control, isolating the room from the central HVAC system.
Learn how Community Health Net created Negative & Positive Pressure Environments to create better patient outcomes and safer spaces for employees and patients. Watch the video below.
For more information about our systems, contact us today. You can also request a quote to get started on a custom solution for your project.
Negative pressure rooms control airborne pathogens by exhausting contaminated air from the building while preventing the air from leaking into other parts of the facility. These rooms are a necessity to maintain the safety of guests, patients, and hospital staff.
At Air Innovations, Inc., our expertise in negative pressure HVAC systems will ensure that your hospital’s negative pressure rooms comply with industry standards.
What Are Negative Pressure Rooms?
Negative pressure rooms have inside air pressure that is lower than the air pressure outside of the room. This serves to prevent contaminated air from exiting the room while allowing non-contaminated air to flow into it. Contaminated air flows through a controlled HVAC system, where the air is purified using specialized filters before it exhausts from the facility.
Creating Negative Air Pressure in a Hospital Room
Negative pressure rooms are crucial in hospital settings as they isolate airborne diseases like COVID-19, SARS, and MERS from the rest of the facility and prevent them from spreading to patients, staff, and guests. A negative pressure room requires a dedicated space, where a barrier will keep the room as air-tight as possible. For isolation rooms in more open areas, a heavy plastic curtain can block air circulation. If the area has a door, it is important to block any gaps to create a tight seal.
When establishing an isolation room in a hospital, the HVAC system will require adjustments to ensure the room has a continuous inflow of fresh air. The contaminated air must be forced out through exhaust vents with a filtration system to purify the air before it exits the facility. An existing HVAC system may be suitable, or a portable contamination system can be used to focus on a particular area.
Types of Negative Pressure Isolation Rooms
There are two classes of negative pressure isolation rooms, class N and class Q. A class N room isolates airborne diseases within a room to protect the facility from exposure. They are typically near the entrance of an inpatient ward to prevent the spread of the disease during patient transport.
Class Q rooms also isolate airborne diseases but implement stricter safeguards. Some primary features include an anteroom, self-closing doors, a private restroom to keep the isolation room sealed, and a ventilation system that prevents exhausted air from re-entering the isolation room. Class Q rooms also feature a monitoring system that alerts staff if the pressure changes. These are all crucial features to ensure optimal infection control.
Hospital Spaces to Negatively Pressurize
Various hospital spaces should be negatively pressurized for safety and compliance. According to ANSI/ASHE/ASHRAE standard 170-2017 of the 2018 FGI guidelines, negative pressure spaces include but are not limited to:
Isolation Rooms for Airborne Infections
Autopsy Rooms
Bathrooms
Public Waiting Areas and Radiology Department Waiting Areas
Emergency Department Decontamination Bays
Various Laboratory Work Areas
Triage
Janitor’s Closets
Sterile Processing Areas and Soiled Decontamination Areas
Soiled Workrooms and Holding Rooms
Soiled Linen Sorting and Storage Areas
General patient examination, X-ray, and nursery areas typically do not require negative pressure rooms.
Testing and Monitoring Room Pressure
Monitoring for consistent low pressure in an isolation room is vital to ensure the safety of a facility. While a tissue or smoke capsule can confirm if the room is pressurized, modern equipment provides continuous monitoring of the room’s pressure. Electronic monitoring devices can be placed inside the isolation room and outside to trigger an alarm when the pressure reaches a set threshold. Regular inspection is necessary to ensure the devices are not contaminated or broken.
Contact the Experts at Air Innovations for Custom HVAC Systems
Negative pressure rooms are vital to controlling airborne diseases in a hospital facility. When setting up a negative pressure room, the experts at Air Innovations, Inc. can create a custom HVAC solution for your facility.
Air Innovations offers specialty environment control units to meet the needs of various critical applications. Our IsolationAir® portable contamination systems deploy quickly to isolate a sterile environment and prevent cross-contamination. These systems come equipped with UV sterilization, HEPA filtration, and ductwork connections. Whether you need to turn a room into a negative or positive pressure environment, our IsolationAir® system offers the ideal solution.
Our expertise will ensure your isolation rooms are compliant with ASHRAE, AIA, and CDC guidelines to protect patients, staff, and guests. Contact us to speak with a representative or request a quote to learn more.
All heating and cooling air duct systems naturally collect dust and contaminants. Clean rooms, such as those used in the electronics, pharmaceutical, and medical industries, require a controlled environment free of dust, airborne particles, and other contaminants. Ultra low particulate air (ULPA) filters and high efficiency particulate air (HEPA) filters are used in commercial air filtration systems to trap extremely small particulate contaminants.
ULPA vs. HEPA Filter
ULPA and HEPA filters share many characteristics but differ in some crucial aspects. Both filters use layers of dense fibers to create a fine mesh filter that removes contaminants as air is forced through them. Both HEPA and ULPA filters use a combination of three main methods to trap contaminants: diffusion, interception, and inertial impaction.
ULPA filters trap more and smaller particulate matter than HEPA filters. ULPA filters are 99.999% effective at removing submicron particulate matter of 0.12-micron diameter or larger, while HEPA filters are 99.97% effective for eliminating particulate matter of 0.3-micron diameter or larger. HEPA filters can be combined with pre filters to trap larger particles before they come into contact with the main filter.
The higher efficiency rating of the ULPA filter is due to the increased density of the filter medium, which allows airflow up to 50% lower than HEPA filters and requires more power to move air. HEPA filters have a lifespanofup to ten years, whereas the typical life cycle of an ULPA filter ranges from five to eight years. Choosing the right filter for your application depends on containment regulations and standards in your facility.
Which Air Filter is Better – ULPA or HEPA?
Filter manufacturers often stress the superior efficiency rating of ULPA filters when compared to HEPA filters. While ULPA filters trap more and smaller particulates, they are usually less effective at reducing the overall particulate concentration in a typical room than the same air filtration system equipped with HEPA filters. This is due to reduced airflow caused by the dense filter material of ULPA filters. ULPA filters typically pass 20-50% less air than HEPA filters, which results in the room having fewer air changes per hour.
There are a variety of HEPA filters available, some of which are more complex than others. These complex HEPA filters exceed the typical MERV scale of rating, making them the most effective and popular option for many industries.
Choosing the Best Air Filter for Your Application
Determining the best filter for your application requires a careful analysis of your needs and any containment regulations for your facility, including the minimum number of air changes required per hour. HEPA and ULPA filters are designed for use in a variety of applications, including industrial vacuum cleaners to remove asbestos, removing toner dust from office equipment, preventing the spread of airborne bacteria in surgical operating rooms, and other crucial medical air filtration applications.
Industries such as pharmaceutical, photography, electronics, and more all rely on air filtration systems to protect their equipment and keep people safe. Understanding the requirements of your application and the level of effectiveness needed will help you choose the right air filter for your needs.
Air Filtration Solutions from Air Innovations
At Air Innovations, we are experts at designing and building air filtration systems for applications that are difficult to address with standard HVAC equipment. We specialize in creating custom solutions that meet containment regulations and any other standards required for your application. Our mission is to design and build an air filtration system that you can rely on to meet the precise tolerances and parameters you need. To request a quote for your application or to learn more about our air filtration systems, contact us today.
Cleanrooms are integral to countless operations around the world. Scientists, manufacturers, and a bevy of other industry professionals rely on these rooms to mitigate the risk of contamination in products or processes. It’s important to understand the different cleanroom classifications and guidelines behind how these rooms are constructed and utilized to determine which is the best fit for your application.
Cleanrooms are man-made, controlled environments. These spaces are designed and built specifically for use in industries which rely on extreme cleanliness and predictability. Manufacturing and scientific research applications regularly utilize cleanrooms to perform daily tasks and help with specialized projects. Virtually any industry involving work that could be negatively impacted by small particles necessitates the use of cleanrooms.
A well-conditioned cleanroom offers researchers and other workers the opportunity to perform tasks in an environment with low levels of pollutants. That means that common problems like dust, chemical vapors, and airborne microbes can’t interfere with the work at hand.
Cleanroom Classifications
Cleanrooms are subject to a range of classifications based on their capabilities and intended applications. The functionality of the cleanroom and the quality of air it facilitates will largely determine the classification.
Cleanroom classifications measures how many particles of a certain size (over 0.5 mm) exist within one cubic foot of air inside the room. FED-STD-209E regulations classified cleanrooms based on the allowable particles contained within each cubic meter of air in conjunction with the size of said particles. These regulations are still referenced frequently when determining cleanroom requirements but have largely been replaced by the stricter International Standards Organization (ISO) classifications.
ISO 14644-1:2015 Cleanrooms and Associated Controlled Environments ranks cleanrooms in terms from function on a scale from 1–9. A cleanroom classified as ISO Class 1 exemplifies the highest possible cleanliness and air purity standards, while an ISO Class 9 would have the lowest requirements. The following table demonstrates the exacting requirements for each cleanroom classification:
ISO 14644-1: 2015
FED_STD-209E
Maximum Allowable Particles in One Cubic Meter of Air
Size of Particles
> 0.1 micron
> 0.2 micron
> 0.3 micron
> 0.5 micron
> 1 micron
> 5 microns
Class 1
N/A
10
2
0
0
0
0
Class 2
N/A
100
24
10
4
0
0
Class 3
Class 1
1,000
237
102
35
8
0
Class 4
Class 10
10,000
2,370
1,020
352
83
0
Class 5
Class 100
100,000
23,700
10,200
3,520
832
29
Class 6
Class 1,000
1,000,000
237,000
102,000
35,200
8,320
293
Class 7
Class 10,000
N/A
N/A
N/A
352,000
83,200
2,930
Class 8
Class 100,000
N/A
N/A
N/A
3,520,000
832,000
29,300
Class 9
Standard room air
N/A
N/A
N/A
35,200,000
8,320,000
293,000
Cleanroom Design
A cleanroom’s design will be directly influenced by its required ISO classification. The amount of square footage that an organization can set aside for their cleanroom impacts numerous components of the room—the clean zone, airlocks, and gowning room must all be considered carefully as well. The latter areas must be carefully designed to mitigate particle migration from the exterior into the cleanroom.
Methods for improving the cleanliness capabilities of a cleanroom include:
Adding airlocks
Improved filtration
Increasing the number of air changes per hour
Cleanroom Services From Air Innovations
Since our founding in 1986, Air Innovations has operated by a commitment to continuous innovation and growth. As such, we are continually improving our capabilities and offerings. Our expert staff designs and manufactures HVAC systems for use in a variety of cleanroom applications and other critical environments.
Interested in learning more about cleanrooms? Download our “Cleanroom Technology” whitepaper. The whitepaper illustrates how temperature, humidity, filtration, and pressure can affect applications. We also have whitepapers available covering the pharmaceutical industry, the semiconductor industry, and our Micro Environments product line. These whitepapers can be found here. More information regarding our work with cleanrooms and other industries can be found on our case studies page.
HVAC systems are essential components in the functionality and appeal of all modern buildings. Well-designed and efficient HVAC systems go well beyond ensuring comfortable temperatures and fresh air for facilities. They also play a key role in the production and testing processes of a broad spectrum of industries.
HVAC systems play a crucial role in pharmaceutical engineering and manufacturing because they have a direct impact on the production environment. Optimized HVAC units can help pharmaceutical companies Mining and Drilling, pass inspections, and remain CGMP-compliant, and more.
All You Need to Know About Specialized HVAC Systems
What is a Specialized HVAC System?
The acronym HVAC stands for heating, ventilation, and air conditioning. Specialized HVAC systems control the temperature, humidity level, and air quality in a space to ensure the required specifications for your application are met.
Types of HVAC Systems We Design & Manufacture
We specialize in the design and manufacture of advanced HVAC systems for the precise control of temperature, humidity, filtration, and pressurization for equipment and processes. The three main configurations of HVAC systems we manufacture are integrated, mounted, and standalone in standard or custom solutions.
Integrated HVAC
Integrated solutions are designed to fit seamlessly within existing equipment structure, allowing for a smaller size and footprint, greater system efficiency, and lower installation cost.
Mounted HVAC
ECUs that are mounted to an existing system can be designed to meet system weight constraints, provide a reduced ECU footprint, and offer close proximity to the process.
Standalone HVAC
Standalone units can be placed in the space surrounding your equipment and offer maximum flexibility in system location, installation, configuration, and performance capability.
Explosion-Proof HVAC
Less common but no less critical, explosion-proof HVAC systems are an essential aspect of many industrial applications. For example, ore mining/processing facilities can make use of these units to prevent an explosion of coal dust particles in the air.
Other industries that utilize explosion-proof HVAC systems include:
Nowadays, many off-the-shelf explosion-proof units are available. However, companies that require explosion-proof environmental control units often need to ensure that their HVAC systems supplier has the capability to provide a tailored solution for their particular application.
Industries and Applications
Industries ranging from homeland security to aerospace use specialized HVAC solutions as an essential part of their daily operations. The following are some examples of specific industries and applications that utilize HVAC systems.
Aerospace applications require strict environmental control in everything from research and development to launch areas. At Air Innovations, we’ve supported a variety of unique aerospace projects, such as clean room filtration, environmentally controlled transportation of aerospace components, and strict environmental control of launch areas.
For example, one rocket’s fueling system demanded a dry dew point of -22° C just before launch. Any remaining moisture would condense and transform into ice on the rocket’s piping, creating a dangerous situation. The solution to this quandary was an in-line desiccant dryer surrounded by two tailored environmental control units used to eliminate moisture and maintain tight temperature tolerances.
Durable HVAC units assist in temperature and humidity maintenance at airport terminals, including security checkpoints and baggage claim areas. Additionally, explosives detection devices (EDDs) at airports demand strict internal control of temperature and humidity variables in order to function properly.As such, the Homeland Security Department relies on specialized HVAC units for these applications.
Mining and drilling companies use environmental control units to keep electrical cabinets of centrifuge machines cool. Centrifuges eliminate slurry during drilling operations, and are therefore an indispensable component of the overall extraction process. ECUs that keep their cabinets cool help prevent overheating, fires, explosions, and other dangerous circumstances.
Biotech and pharmaceutical companies frequently employ specialized HVAC units for strict control over temperature, humidity, and dew point, especially when handling sensitive equipment, or performing processes that require certain environmental conditions to succeed.
Computer rooms, laboratories, hospitals, and process isolators often make use of cleanrooms. HVAC units designed for cleanroom use often come with features such as positive/negative pressure control, once-through or recirculating air flow, and alarms triggered by the slightest variance from set tolerances.
The Pharmaceutical Industry and HVAC Systems
The Importance of HVAC Systems for the Pharmaceutical Industry
Why are well-functioning HVAC systems so important to the pharmaceutical industry today? While there are many factors involved, but here are just two of the reasons they are so essential:
Modern diagnostic machines need to operate within very strict temperature and humidity tolerances so that the integrity of powdered and fluid reagents is not comprised. The consequences of a misdiagnosis or false reading from the introduction of unanticipated moisture, for example, could be serious for both patient and medical provider alike. Customized HVAC units that ensure stable environmental conditions—whether cold, hot, or dry—and integrate well into often limited space, are key pieces of an effective diagnostic process.
Moisture can be one of the worst enemies of modern medicine production. In every phase of production—from milling to compounding to coating—excess moisture can cause manufacturing inefficiencies, weaken the medicine’s effect, or in the worst-case scenario, completely ruin an entire batch of product. Specialized HVAC units that enforce a specified dew point based on the application all but guarantee that there will be no excess moisture from the air to cause production issues.
System Design
There are several design considerations that engineers must apply to HVAC systems intended for pharmaceutical applications. Ideally, architectural components should dovetail with HVAC design factors, such as pressure differential cascades and cross-contamination control. Adequate ventilation and filtration are important considerations for laboratory testing areas and cleanrooms.
Additionally, HVAC engineers must implement systems that ensure strict control over temperature, relative humidity and/or dew point, without interfering with the actual pharmaceutical manufacturing process.
Operational HVAC Optimization in Pharmaceutical Facilities
After HVAC room requirements have been established, there are ways to optimize HVAC system operations to keep costs low and efficiencies high. Some optimization measures could include:
The reduction of air-change rates
Optimized temperature and humidity limits
Improved control sequences for use of floating set-points and dead-band control
Changeover to a two-port variable volume system
The addition of airflow meters and air volume control components
Efficient and Custom HVAC Solutions at Air Innovations
Air Innovations provides several HVAC products specifically designed for use in the pharmaceutical industry. These include:
In another case, a client needed a chemical process control unit that would hold set temperature and humidity levels in widely varying conditions all over the globe, while also operating on a continuous, year-round basis. Air Innovations provided an HVAC unit that depends on two independent cooling coils, along with process fans that alternate operation time. Various sensor inputs help to manage switch-over intervals. As a result, the cooling coils continue running without defrost interruptions, even in sub-zero temperatures.
HVAC systems are an essential aspect of pharmaceutical manufacturing. If you’d like to learn more about how Air Innovations can provide a workable, highly-customized, and efficient HVAC solution for your manufacturing needs, reach out to us today.
Effective positive and negative pressure rooms are an important part of industrial climate control systems. In medical settings, these rooms prevent the spread of infectious contaminants and maintain sterile or restricted spaces and are also referred to as ProtectiveEnvironments (positive pressure rooms) and Airborne Infection Isolation Rooms (AIIR) (negative pressure rooms). Negative or positive pressure rooms are a necessary part of a wide range of medical and research environments, as they help maintain clean conditions in the smallest clinic to the largest hospital.
Understanding Positive and Negative Pressure Rooms
Positive pressure rooms maintain a higher pressure inside the treated area than that of the surrounding environment. This means air can leave the room without circulating back in. In this way, any airborne particle that originates in the room will be filtered out. Germs, particles, and other potential contaminants in the surrounding environment will not enter the room. In medical settings, a positive pressure room (protective environment) allows staff to keep vulnerable patients safe from infections and disease.
In contrast, a negative pressure room uses lower air pressure to allow outside air into the segregated environment. This traps and keeps potentially harmful particles within the negative pressure room by preventing internal air from leaving the space. Negative pressure rooms in medical facilities isolate patients with infectious conditions (AIIR) and protect people outside the room from exposure.
Positive and negative pressure rooms both require a number of additional components to remain effective: Building positive and negative pressure rooms requires the use of specialized construction and climate control equipment. A minimum of 12 air-flow changes each hour must be maintained in order to sustain the desired environment and depending on the size and purpose of the room, more may be necessary.
Recirculation of air through HEPA filters to control the movement of airborne contaminants
Self-closing entryway with an adequate seal
Thoroughly sealed floors, ceiling, walls, and windows
Fans and ductwork to move air in the desired directions
A monitoring system that allows users to adjust pressure when necessary
Intermediate environment between the pressure room and outside environment for deliveries, observations, and protective gear storage
Some medical facilities additionally incorporate UV radiation into the system to help maintain a sterile environment. Using UV light in a filtration system sterilizes particles and reduces viruses (such as coronavirus) in the quarantine space, helping to protect healthcare workers who enter the room to service the quarantined patient.
Positive and Negative Pressure Rooms in Hospitals
Positive and negative pressure rooms are an essential part of controlling the spread of infectious diseases within large facilities such as hospitals. Negative pressure rooms (airborne infection isolation rooms) are a common solution in infection control efforts. Hospitals use them in inpatient rooms to ensure infectious germs don’t spread throughout the facility via the HVAC system. Hospitals usually design the following areas as negative pressure environments:
Waiting areas, especially in emergency rooms
Triage areas
Bathrooms
AII (airborne infection isolation) rooms
Autopsy and dark rooms
Soiled laundry areas
Decontamination spaces
Positive pressure rooms are usually used in scenarios that must continually filter harmful contaminants out of the environment. This makes them helpful when treating patients with compromised immune systems because the introduction of any harmful element will be efficiently filtered out. They’re also used in situations that must continually maintain a specific type of atmosphere in a room, such as human and animal nurseries. Other uses of positive pressure rooms include in vitro fertilization labs and operating theaters.
Installing Your Pressurized Room
Hospital managers must carefully plan their pressurized room to ensure they satisfy the following requirements:
The room fits the facility’s needs and space
The room conforms to applicable legal regulations
The room fully protects patients and the general public from the spread of infectious diseases
Efficiently installed positive and negative pressure rooms mean the difference between a healthy environment for hospital patients and one compromised by infectious pathogens.
Dew point and humidity are important environmental factors in industrial settings. Although both these terms describe the amount of moisture present in an environment, some crucial differences exist between them.
Understanding the differences between an environment’s dew point and humidity is essential for selecting an optimal humidification or dehumidification system for your business or facility. Knowing the amount of moisture present in your internal climate as well as the point at which it condenses will allow you to better control the systems that govern these factors.
Understanding Humidity and Dew Point Control—Why Is It Needed?
Humidity measures the amount of water vapor present in the air. Absolute humidity defines how much water the surrounding air holds, and relative humidity is the percentage of air that contains liquid vapor at the time point of measurement. Specific humidity expresses the relationship between moist and dry air in a single system.
An environment’s dew point is the temperature needed for water vapor to condense and form on surfaces. A higher dew point means a higher atmospheric temperature at which dew forms.
Another way to describe an area’s dew point is the point at which its air reaches 100% relative humidity. At this point, the air has absorbed the maximum amount of moisture that it can retain and introducing any further moisture to the system results in fog or precipitation. This also occurs when the temperature is reduced in an environment that has 100% relative humidity.
A wide variety of industries rely on controlling the relative humidity and dew points to maintain good product quality and optimal working conditions:
Food distribution centers use humidity control systems to increase shelf life and avoid exorbitant energy prices
Humidity control prevents the spread of pathogens in medical facilities
Production facilities that work with hazardous chemicals control air moisture content to reduce the risk of volatile chemical reactions
Storage facilities use humidity control systems to keep porous or delicate materials from spoiling
Finding the correct moisture content for a room also increases its comfort for people. Commercial and industrial operations use humidity control systems to maintain comfortable internal environments without incurring large energy bill fluctuations.
Humidity Control Solutions for Multiple Industries
Environmental control companies must constantly innovate to create humidity control systems optimized for specific industrial environments. To use a specific example, biotherapy reagent packaging plants require systems that successfully balance high evaporative loads and heat. Designers of humidity controls for these kinds of facilities must customize clean rooms to consistently maintain high safety and health standards.
In another example, aerospace OEMs require large industrial cooling systems to maintain good manufacturing environments for delicate technological systems. Humidification control systems must meet narrow temperature, dew point, and humidity requirements to prevent corrosion or damage to sensitive electronic equipment.
Semiconductor manufacturers also rely on effective humidity control systems for this reason. Climate control systems for these facilities must achieve critical tolerances for humidity and temperature in both near-saturation environments and dry or trace-moisture facilities. Additionally, it is especially essential that if an application is using outside air, limited humidity fluctuation rates are considered for the process.
Control Moisture Buildup with Air Innovations
Humidity control in industrial environments improves product quality, industrial compliance, and employee, customer, and patron safety. Air Innovations designs a full suite of humidification control systems for settings that range from industrial clean rooms, HVAC systems, and factory floors.
If you would like to learn more about how we can help control the moisture content of your facility or business, be sure to contact us today.
If you would like to see case studies, view our general case studies page. We also have whitepapers available covering multiple industries including the the aerospace industry, the semiconductor industry, the pharmaceutical industry, and our Micro Environments product line.
