Ventilation has a long history dating back to early human settlements. It was originally used for thermal comfort and health reasons, removing odors, moisture, and combustion by-products from indoor spaces. Over time, the understanding of ventilation evolved from early passive designs inspired by termite mounds and bee hives to active mechanical systems. Standards and guidelines for ventilation were developed by organizations like ASHRAE to provide minimum requirements. However, energy crises and new indoor pollutants challenged existing paradigms, obscuring the importance of ventilation to indoor air quality. Recent research on key pollutants like PM2.5 is bringing renewed focus to the role of proper ventilation in building health, productivity and sustainability.
Chilling Tales: The Fascinating History Of Air ConditioningEZAirconServicing
With summer just around the corner, the demand for air conditions and aircon servicing to make our lives more comfortable in the sweltering heat of Singapore is high. Visit https://ezaircon.sg/ to learn more.
BIBLIOGRAPHY OF AIR PURIFIERS
1
BIBLIOGRAPHY OF AIR PURIFIERS
2
Air Purifiers: Bibliography
The History of Air Purifiers is an article under the General Health section of the Free Drinking Water site. The article discusses the history and technology about air purifiers. In that period of time, they are just made as simple protective air respirators that can protect users from inhaling the negative elements in the air.The authors contend that the concept of air purification, as well as air purification products, have been invented for quite some time. For instance, the breathing mask used by firefighters was invented in 1823 by Charles and John Dean. In 1854, John Stenhouse made an improvement to the technology by inventing a filter design based on charcoal. In 1871, John Tyndall improved the technology further by inventing a respirator. The article announced that the concept of air purification came out due to firefighting. Nowadays, there are many companies that invest those productions in the commercialization of these air cleaning products. They put those cleaning product into the market and put them in to large-scale production. Several companies are investing their capitals to the further development of the air purifier technology. The technology of HEPA air filter was a significant mile stone in the technology used to clean air(APEC,nd).
This technology has gradually evolved to be adjustable, affordable and feasible for home use. There are many companies that invest those productions in the commercialization of these air cleaning products. According to APEC, the technology about air purification increases alongside an advancement in the commercial viability of air-purifying products. They put those cleaning product into the market and put them in to large-scale production.However, it is also claims that Multiple Chemical Sensitivity has been a problem to air filtration over the years. Although the problem is being identified effectively, it has not been fully endorsed by the medical community. As for now, air-cleaning products are doing better than before. Microscopic allergens, toxic gasses and other pollutants including trapping particles are being dealt with effectively. The article plans that the future will bring about paramount advances that will make the quality of air much better (APEC,nd).
The main purpose of this article is to bring to light the facts about air purification technology. The authors mentioned that most consumers have a very little idea about how air purification technology came into existence. Remarkably, it can be find from the article that the air purifier was invented to eliminate different types of harmful and irritating contaminants from the air. Although the purifiers are mainly used by people who have respiratory problems or those who suffe ...
AARC Clinical Practice Guideline
Humidification during Mechanical Ventilation
HMV 1.0 PROCEDURE:
The addition of heat and moisture to inspired gases delivered to the patient during mechanical ventilatory support via an artificial airway
HMV 2.0 DESCRIPTION/DEFINITION:
When the upper airway is bypassed, humidification during mechanical ventilation is necessary to prevent hypothermia, inspissation of airway secretions, destruction of airway epithelium, and atelectasis.(1-7) This may be accomplished using either a heated humidifier or a heat and moisture exchanger (HME). (HMEs are also known as hygroscopic condenser humidifiers, or artificial noses). The chosen device should provide a minimum of 30 mg H2O/L of delivered gas at 30°C.(8,29) Heated humidifiers operate actively to increase the heat and water vapor content of inspired gas.(11-14) HMEs operate passively by storing heat and moisture from the patient's exhaled gas and releasing it to the inhaled gas.(I5-25)
Chilling Tales: The Fascinating History Of Air ConditioningEZAirconServicing
With summer just around the corner, the demand for air conditions and aircon servicing to make our lives more comfortable in the sweltering heat of Singapore is high. Visit https://ezaircon.sg/ to learn more.
BIBLIOGRAPHY OF AIR PURIFIERS
1
BIBLIOGRAPHY OF AIR PURIFIERS
2
Air Purifiers: Bibliography
The History of Air Purifiers is an article under the General Health section of the Free Drinking Water site. The article discusses the history and technology about air purifiers. In that period of time, they are just made as simple protective air respirators that can protect users from inhaling the negative elements in the air.The authors contend that the concept of air purification, as well as air purification products, have been invented for quite some time. For instance, the breathing mask used by firefighters was invented in 1823 by Charles and John Dean. In 1854, John Stenhouse made an improvement to the technology by inventing a filter design based on charcoal. In 1871, John Tyndall improved the technology further by inventing a respirator. The article announced that the concept of air purification came out due to firefighting. Nowadays, there are many companies that invest those productions in the commercialization of these air cleaning products. They put those cleaning product into the market and put them in to large-scale production. Several companies are investing their capitals to the further development of the air purifier technology. The technology of HEPA air filter was a significant mile stone in the technology used to clean air(APEC,nd).
This technology has gradually evolved to be adjustable, affordable and feasible for home use. There are many companies that invest those productions in the commercialization of these air cleaning products. According to APEC, the technology about air purification increases alongside an advancement in the commercial viability of air-purifying products. They put those cleaning product into the market and put them in to large-scale production.However, it is also claims that Multiple Chemical Sensitivity has been a problem to air filtration over the years. Although the problem is being identified effectively, it has not been fully endorsed by the medical community. As for now, air-cleaning products are doing better than before. Microscopic allergens, toxic gasses and other pollutants including trapping particles are being dealt with effectively. The article plans that the future will bring about paramount advances that will make the quality of air much better (APEC,nd).
The main purpose of this article is to bring to light the facts about air purification technology. The authors mentioned that most consumers have a very little idea about how air purification technology came into existence. Remarkably, it can be find from the article that the air purifier was invented to eliminate different types of harmful and irritating contaminants from the air. Although the purifiers are mainly used by people who have respiratory problems or those who suffe ...
AARC Clinical Practice Guideline
Humidification during Mechanical Ventilation
HMV 1.0 PROCEDURE:
The addition of heat and moisture to inspired gases delivered to the patient during mechanical ventilatory support via an artificial airway
HMV 2.0 DESCRIPTION/DEFINITION:
When the upper airway is bypassed, humidification during mechanical ventilation is necessary to prevent hypothermia, inspissation of airway secretions, destruction of airway epithelium, and atelectasis.(1-7) This may be accomplished using either a heated humidifier or a heat and moisture exchanger (HME). (HMEs are also known as hygroscopic condenser humidifiers, or artificial noses). The chosen device should provide a minimum of 30 mg H2O/L of delivered gas at 30°C.(8,29) Heated humidifiers operate actively to increase the heat and water vapor content of inspired gas.(11-14) HMEs operate passively by storing heat and moisture from the patient's exhaled gas and releasing it to the inhaled gas.(I5-25)
CASE STUDY 5Exploring Innovation in Action The Dimming of the.docxwendolynhalbert
CASE STUDY 5
Exploring Innovation in Action: The Dimming of the Light Bulb
In the beginning….
God said let there be light. And for a long time this came from a rather primitive but surprisingly effective method – the oil lamp. From the early days of putting simple wicks into congealed animal fats, through candles to more sophisticated oil lamps, people have been using this form of illumination. Archaeologists tell us this goes back at least 40,000 years so there has been plenty of scope for innovation to improve the basic idea! Certainly by the time of the Romans, domestic illumination – albeit with candles – was a well-developed feature of civilised society.
Not a lot changed until the late eighteenth century when the expansion of the mining industry led to experiments with uses for coal gas – one of which was as an alternative source of illumination. One of the pioneers of research in the coal industry – Humphrey Davy – invented the carbon arc lamp and ushered in a new era of safety within the mines, but also opened the door to alternative forms of domestic illumination and the era of gas lighting began.
But it was not until the middle of the following century that researchers began to explore the possibilities of using a new power source and some new physical effects. Experiments by Joseph Swann in England and Moses Farmer in the USA (amongst others) led to the development of a device in which a tiny metal filament enclosed within a glass envelope was heated to incandescence by an electric current. This was the first electric light bulb – and it still bears more than a passing resemblance to the product found hanging from millions of ceilings all around the world.
By 1879 it became clear that there was significant commercial potential in such lighting – not just for domestic use. Two events occurred during that year which were to have far-reaching effects on the emergence of a new industry. The first was that the city of Cleveland – although using a different lamp technology (carbon arc) – introduced the first public street lighting. And the second was that patents were registered for the incandescent filament light bulb by Joseph Swann in England and one Thomas Edison in the USA.
Needless to say the firms involved in gas supply and distribution and the gas lighting industry were not taking the threat from electric light lying down and they responded with a series of improvement innovations which helped retain gas lighting’s popularity for much of the late nineteenth century. Much of what happened over the next 30 years is a good example of what is sometimes called the ‘sailing ship effect’. That is, just as in the shipping world the invention of steam power did not instantly lead to the disappearance of sailing ships but instead triggered a whole series of improvement in that industry, so the gas lighting industry consolidated its position through incremental product and process innovations.
But electric lighting was also improvin ...
CASE STUDY 5Exploring Innovation in Action The Dimming of the Lig.docxPazSilviapm
CASE STUDY 5
Exploring Innovation in Action: The Dimming of the Light Bulb
In the beginning….
God said let there be light. And for a long time this came from a rather primitive but surprisingly effective method – the oil lamp. From the early days of putting simple wicks into congealed animal fats, through candles to more sophisticated oil lamps, people have been using this form of illumination. Archaeologists tell us this goes back at least 40,000 years so there has been plenty of scope for innovation to improve the basic idea! Certainly by the time of the Romans, domestic illumination – albeit with candles – was a well-developed feature of civilised society.
Not a lot changed until the late eighteenth century when the expansion of the mining industry led to experiments with uses for coal gas – one of which was as an alternative source of illumination. One of the pioneers of research in the coal industry – Humphrey Davy – invented the carbon arc lamp and ushered in a new era of safety within the mines, but also opened the door to alternative forms of domestic illumination and the era of gas lighting began.
But it was not until the middle of the following century that researchers began to explore the possibilities of using a new power source and some new physical effects. Experiments by Joseph Swann in England and Moses Farmer in the USA (amongst others) led to the development of a device in which a tiny metal filament enclosed within a glass envelope was heated to incandescence by an electric current. This was the first electric light bulb – and it still bears more than a passing resemblance to the product found hanging from millions of ceilings all around the world.
By 1879 it became clear that there was significant commercial potential in such lighting – not just for domestic use. Two events occurred during that year which were to have far-reaching effects on the emergence of a new industry. The first was that the city of Cleveland – although using a different lamp technology (carbon arc) – introduced the first public street lighting. And the second was that patents were registered for the incandescent filament light bulb by Joseph Swann in England and one Thomas Edison in the USA.
Needless to say the firms involved in gas supply and distribution and the gas lighting industry were not taking the threat from electric light lying down and they responded with a series of improvement innovations which helped retain gas lighting’s popularity for much of the late nineteenth century. Much of what happened over the next 30 years is a good example of what is sometimes called the ‘sailing ship effect’. That is, just as in the shipping world the invention of steam power did not instantly lead to the disappearance of sailing ships but instead triggered a whole series of improvement in that industry, so the gas lighting industry consolidated its position through incremental product and process innovations.
But electric lighting was also improving and th.
CASE STUDY 5Exploring Innovation in Action The Dimming of the.docxwendolynhalbert
CASE STUDY 5
Exploring Innovation in Action: The Dimming of the Light Bulb
In the beginning….
God said let there be light. And for a long time this came from a rather primitive but surprisingly effective method – the oil lamp. From the early days of putting simple wicks into congealed animal fats, through candles to more sophisticated oil lamps, people have been using this form of illumination. Archaeologists tell us this goes back at least 40,000 years so there has been plenty of scope for innovation to improve the basic idea! Certainly by the time of the Romans, domestic illumination – albeit with candles – was a well-developed feature of civilised society.
Not a lot changed until the late eighteenth century when the expansion of the mining industry led to experiments with uses for coal gas – one of which was as an alternative source of illumination. One of the pioneers of research in the coal industry – Humphrey Davy – invented the carbon arc lamp and ushered in a new era of safety within the mines, but also opened the door to alternative forms of domestic illumination and the era of gas lighting began.
But it was not until the middle of the following century that researchers began to explore the possibilities of using a new power source and some new physical effects. Experiments by Joseph Swann in England and Moses Farmer in the USA (amongst others) led to the development of a device in which a tiny metal filament enclosed within a glass envelope was heated to incandescence by an electric current. This was the first electric light bulb – and it still bears more than a passing resemblance to the product found hanging from millions of ceilings all around the world.
By 1879 it became clear that there was significant commercial potential in such lighting – not just for domestic use. Two events occurred during that year which were to have far-reaching effects on the emergence of a new industry. The first was that the city of Cleveland – although using a different lamp technology (carbon arc) – introduced the first public street lighting. And the second was that patents were registered for the incandescent filament light bulb by Joseph Swann in England and one Thomas Edison in the USA.
Needless to say the firms involved in gas supply and distribution and the gas lighting industry were not taking the threat from electric light lying down and they responded with a series of improvement innovations which helped retain gas lighting’s popularity for much of the late nineteenth century. Much of what happened over the next 30 years is a good example of what is sometimes called the ‘sailing ship effect’. That is, just as in the shipping world the invention of steam power did not instantly lead to the disappearance of sailing ships but instead triggered a whole series of improvement in that industry, so the gas lighting industry consolidated its position through incremental product and process innovations.
But electric lighting was also improvin ...
CASE STUDY 5Exploring Innovation in Action The Dimming of the Lig.docxPazSilviapm
CASE STUDY 5
Exploring Innovation in Action: The Dimming of the Light Bulb
In the beginning….
God said let there be light. And for a long time this came from a rather primitive but surprisingly effective method – the oil lamp. From the early days of putting simple wicks into congealed animal fats, through candles to more sophisticated oil lamps, people have been using this form of illumination. Archaeologists tell us this goes back at least 40,000 years so there has been plenty of scope for innovation to improve the basic idea! Certainly by the time of the Romans, domestic illumination – albeit with candles – was a well-developed feature of civilised society.
Not a lot changed until the late eighteenth century when the expansion of the mining industry led to experiments with uses for coal gas – one of which was as an alternative source of illumination. One of the pioneers of research in the coal industry – Humphrey Davy – invented the carbon arc lamp and ushered in a new era of safety within the mines, but also opened the door to alternative forms of domestic illumination and the era of gas lighting began.
But it was not until the middle of the following century that researchers began to explore the possibilities of using a new power source and some new physical effects. Experiments by Joseph Swann in England and Moses Farmer in the USA (amongst others) led to the development of a device in which a tiny metal filament enclosed within a glass envelope was heated to incandescence by an electric current. This was the first electric light bulb – and it still bears more than a passing resemblance to the product found hanging from millions of ceilings all around the world.
By 1879 it became clear that there was significant commercial potential in such lighting – not just for domestic use. Two events occurred during that year which were to have far-reaching effects on the emergence of a new industry. The first was that the city of Cleveland – although using a different lamp technology (carbon arc) – introduced the first public street lighting. And the second was that patents were registered for the incandescent filament light bulb by Joseph Swann in England and one Thomas Edison in the USA.
Needless to say the firms involved in gas supply and distribution and the gas lighting industry were not taking the threat from electric light lying down and they responded with a series of improvement innovations which helped retain gas lighting’s popularity for much of the late nineteenth century. Much of what happened over the next 30 years is a good example of what is sometimes called the ‘sailing ship effect’. That is, just as in the shipping world the invention of steam power did not instantly lead to the disappearance of sailing ships but instead triggered a whole series of improvement in that industry, so the gas lighting industry consolidated its position through incremental product and process innovations.
But electric lighting was also improving and th.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
Natural farming @ Dr. Siddhartha S. Jena.pptxsidjena70
A brief about organic farming/ Natural farming/ Zero budget natural farming/ Subash Palekar Natural farming which keeps us and environment safe and healthy. Next gen Agricultural practices of chemical free farming.
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...
Ventilation in buildings
1. Ventilation:
The Once & Future King
Max Sherman
Lawrence Berkeley National Lab
ASHRAE Distinguished Lecturer
2. WHAT IS VENTILATION
Medicine: To Exchange
Air In the Lungs
Latin: Ventilare, “to
expose to the wind”
Today: To Bring In
Outdoor Air And Replace
Indoor Air Of The
Occupied Space
Long History
3. WHY DO WE VENTILATE?
Thermal Comfort
Health
Odor
Energy
Moisture
Durability
Safety
Sustainability
WHY DID WE VENTILATE?
Learn from history
Science & Technology
Standards and Guides
4. QUIZ: ROOTS OF VENTILATION
Who Were The
Masters of
Ventilation?
When Was It
Mastered
What Were The Best,
Earliest Techniques?
How Long Has This
Been An Issue?
5. WINNER: EUSOCIAL INSECTS!
TERMITES
High Degree of
Temperature Control
Dynamic Passive
Stack
Model for Indigenous
Nomadic Peoples
BEES
Active Control
“Mechanical
Ventilation”
Model for Fixed
Structures
Value engineering
8. LETS GET NEOLITHIC
People Can’t Wait For Evolution
Fires In Caves Had To Be Ventilated
Banpo Villagers of China Had Chimneys
7000 years ago
Minoan Palace of Knossos Used “Termite”
Ventilation 4000 Years Ago
Egyptians Probably Invented First “Bee”
Fan 3000 Years Ago
10. MINOAN KNOSSOS
4000 yr ago in Crete
Architects of Atlantis
Palace of King Minos
“Termite” Ventilation
Labyrinth was?
Minotaur was?
Daedalus was?
Where did the King Live?
12. LET’S GO A.D.
Combustion was key contaminant
Roman Houses & Large Buildings Had
Designed Ventilation System
Examples from American South-West
Basketweaver Pits at Mesa Verde 750A.D
Designed Ventilation
Combustion outside living space
14. EARLY HEALTH CONCERNS
More Than Combustion
Egyptians Noted Health of Pyramid
Stonecutters Improved With Ventilation
1631 King Charles of England Decreed
That There Must Be Ventilation:
Ceiling at least 10 feet high
Windows taller than they are wide
1st Window industry lobby
16. ENGLISH HISTORY
London Fire of 1666 Improves Buildings
Reversed By 18th Century Window Tax
Parliament “foul, rancid, pestiferous”
Mechanical Ventilation Added in 1734
Burned down a century later
New design study commissioned
Ventilation was a concern
17. EARLY SCIENCE
Egyptian stone carvers
Roman heating systems
Venetian glass
Middle Ages: Contagion from bad air
Lavoisier (1775) discovers CO2
Source of stuffiness (1777)
CO2 debate begins
18. 18th CENTURY EQUIPMENT
Biologically Powered
People
Horses
Fires
Limited Applications
Ventilation
Cooling
19. VENTILATION TECHNOLGY
British science put to use
House of Parliament
Rebuilt after Great Fire of 1666
Sir Christopher Wren design
Mechanical Ventilation Added in 1734
Didn’t work that well in 18th century
Commission does a study in 1830s
Tredgold did the science
21. D. B. REID WROTE THE BOOK
Circa 1844
For many years the
“bible” of ventilation
All manner of topics
from manual to
mechanical, health to
comfort
24. 19th CENTURY EQUIPMENT
Sturtevant from
Shoe-making to
fan-making for dust
Davidson develops
curved blades
Inglis make
American Blower
Co a big deal
25. VENTILATION PROFESSIONALS
Industry leads to engineers
ASHVE: American Society of Heating and
Ventilating Engineers formed 1895
ASHRAE forerunner
27. BRIEF ASHRAE HISTORY
ASHVE formed 1895
Carrier President in
1931 wants ASRE
consolidation
1950: “V” became “A”
Took until 1958 to
become ASHRAE
Logoized 2012
28. EARLY 20th CENTURY
Professional Societies
ASHRAE predecessors
Industry Groups
Appliance Manufacture
Standards
Research
Legislation
30. PARADIGM SHIFTS
Odor-free air is healthy
air paradigm holds
Yaglou writes it into
ASHVE guide
Contagion-prevention
not as important
Windows are better
than fans
32. VENTILATION AS A NON-ISSUE
New paradigms seemed to be working
Problems were not at forefront
Fan and window technologies coexisted
As did architects and engineers
Air conditioning now meant cooling
Compressors cost more than fans
More ventilation was better
Energy, moisture impacts not felt
33. LATE 20th CENTURY
Better Living Through Chemistry
New indoor contaminates abound
Oil shock focusses attention on energy
Push for tighter envelopes,
Push for lower ventilation
Unintended consequences on IAQ
Need new paradigm
34. WE VENTILATE FOR COMFORT
Thermal Comfort (IEQ not IAQ)
Prevents overheating by venting excess heat
Air movement makes us feel cooler
Economizers in dry climates
Odor Control
Not all odors are bad
Occupants are best “sensors” –can take actions
Most odors not controlled by constant ventilation
35. Key Odor: US!
People Emit “Human Bioeffluents”
CO2 is only surrogate
Daily Hygiene of Western World
5 cfm adapted (occupants)
15 cfm unadapted (visitors)
Dominates In High-Density Spaces
Sets Floor Otherwise
36. WE VENTILATE FOR HEALTH
Occupants not usually good sensors
So, we must design healthy buildings
Key Questions:
What are the important contaminants?
How do we measure harm from them?
How do we mitigate that harm?
Contagion not typically a justification
38. MAJOR STUDY @ LBL
Did hazards assessment
Reviewed literature
Combined many disciplines
Did harm/risk analysis
MAGIC HAPPENS
39. CONTAMINANTS OF CONCERN
1. PM2.5 tops the list for harm
2. Moisture is next, but not “contaminant”
3. Product of combustion are next
Acrolein is biggest chronic contributor
Least studied of important compounds
4. Formaldehyde is close: uncertainties
Even though it meets WHO standards
…not counting smoking or Radon or acute
40. STANDARDS MUST EVOLVE
Contaminants require ventilation
From cave-man to euro-man
Rates and design based on expert judgments
From cave-man to euro-man
Science is latecomer
Rates have followed changing paradigms
41. CURRENT ASHRAE STANDARDS
62.1-2013: Non Residential
Users Manual and companion guideline
62.2-2013: Residential
Users Manual and companion guideline
Guideline 10: Indoor Environmental Quality
http://www.ashrae.org/standards
42. The Latest Tool for Good IAQ
ASHRAE’s Indoor Air Quality Guide
Practical guidance on achieving
good IAQ in commercial buildings
Joint effort of ASHRAE, AIA, BOMA,
US EPA, SMACNA, USGBC
200 page book, 500 page CD
Available now
43. SUMMARY
Ventilation was king of Indoor Climate:
Even heating played second fiddle
Willis Carrier thought it the core of Air Conditioning
Energy crisis and changing paradigms obscured its
(and IAQ’s) importance to the public.
Importance to health, productivity, sustainability
bring it back to the fore.
