Temperature has great impact on material selection, colors, adhesives, change of strength, bonding, longevity, aging, financial cost, life cycle, and sustainability.

Temperature discolors the product, the plasticity is lost and the product becomes brittle, and the life expectancy is sharply reduced. Manufactures generally trail the real changing facts, since retooling, innovations, modifications of their existing production line, marketing, or additional cost of goods are not conducive of profit making companies.

In LinkedIn, a short while ago I addressed this, yet the impact and response was not widely received.

The century averaging data is no longer valid. Like in Storm of the Century, the actual years is now more like 125 years and not 100 years. Canada (and I mean the Country North of United States) had 122 degrees F (50 degrees C) temperatures with 486 sudden deaths.

Other impacts are: air conditioning loads will increase, forest fire incidences will increase in acreage and frequency, more power consumption, lack of water to cool the power production systems, and finally power outages.

Politicians will scramble for additional lectures on news media podiums, yet, reality will sink onto the public.

As designers and specifiers of equipment and materials, specially for the exterior, the search must begin now for best possible solutions and designs for the clients.

It is never too late to start.

Dr. Nour

6 2 2021

Dr. Saum K. Nour

This subject, of course like many others dealing with health and safety, has been forefront of my concerns in our industry.

Unfortunately, the cost of construction is the locomotive of most changes in the industry. Not health and safety.

Presentation below was given a while back in 2017, yet I updated and created brand new presentation. I want to thank articles by Ron George, were extremely helpful in packaging this presentation.

Basics of Plastic Piping

1. Chemistry
2. Organic vs inorganic
3. Organic Chemistry: the chemistry of carbon compounds (other than simple salts such as carbonates, oxides, and carbides).
4. Plastic: a synthetic material made from a wide range of organic polymers such as polyethylene, PVC, nylon, etc., that can be molded into shape while soft and then set into a rigid or slightly elastic form.

Common Poly (Many) + mer + s

Section 509.0 of the Uniform Plumbing Code with a brief detour on vented appliance categories I, II, III, and IV.

CPC 2019

509.0 Venting of Appliances

509.1 Listing

Type B and Type B-W gas vents shall comply with UL 441, and Type L gas vents shall comply with UL 641.

509.1.1 Installation

Listed vents shall be installed in accordance with Section 509.0 and the manufacturer’s installation instructions. [NFPA 54:12.2.1]

509.1.2 Prohibited Discharge

Appliance vents shall not discharge into a space enclosed by screens having openings less than 1/4 of an inch (6.4 mm) mesh.

509.2 Connection to Venting Systems

Except as permitted in Section 509.2.1 through Section 509.2.7, all appliances shall be connected to venting systems. [NFPA 54:12.3.1]

509.2.1 Appliances Not Required to Be Vented

The following appliances shall not be required to be vented:

A single listed booster-type (automatic instantaneous) water heater, when designed and used solely for the sanitizing rinse requirements of a dishwashing machine, provided that the appliance is installed with the draft hood in place and unaltered, if a draft hood is required, in a commercial kitchen having a mechanical exhaust system. Where installed in this manner, the draft hood outlet shall not be less than 36 inches (914 mm) vertically and 6 inches (152 mm) horizontally from any surface other than the appliance. [NFPA 54:12.3.2(5)]

Other appliances listed for unvented use and not provided with flue collars. [NFPA 54:12.3.2(10)]

509.2.2 Maximum Input Rating

Where any or all of the appliances in Section 509.2.1(1) and Section 509.2.1(2) are installed so the aggregate input rating exceeds 20 (Btu/h)/ft3 (207 W/m3) of room or space in which it is installed, one or more shall be provided with venting systems or other approved means for conveying the vent gases to the outdoors so that the aggregate input rating of the remaining unvented appliance does not exceed 20 (Btu/h)/ft3 (207 W/m3). [NFPA 54:12.3.2.1]

509.2.3 Adjacent Room or Space

Where the calculation includes the volume of an adjacent room or space, the room or space in which the appliances are installed shall be directly connected to the adjacent room or space by a doorway, archway, or other opening of comparable size that cannot be closed. [NFPA 54:12.3.2.2]

509.2.4 Ventilating Hoods

Ventilating hoods and exhaust systems shall be permitted to be used to vent appliances installed in commercial applications and to vent industrial appliances, particularly where the process itself requires fume disposal. [NFPA 54:12.3.3]

509.2.5 Well-Ventilated Spaces

The operation of industrial appliances such that its flue gases are discharged directly into a large and well-ventilated space shall be permitted. [NFPA 54:12.3.4]

509.2.6 Direct-Vent Appliances

Listed direct-vent appliances shall be installed in accordance with the manufacturer’s installation instructions and Section 509.8.2. [NFPA 54:12.3.5]

509.2.7 Appliances With Integral Vents

Appliances incorporating integral venting means shall be installed in accordance with the manufacturer’s installation instructions, Section 509.8 and Section 509.8.1. [NFPA 54:12.3.6]

509.3 Design and Construction

Venting systems shall be designed and constructed to convey flue, vent, or both gases to the outdoors. [NFPA 54:12.1]

509.3.1 Appliance Draft Requirements

A venting system shall satisfy the draft requirements of the appliance in accordance with the manufacturer’s instructions. [NFPA 54:12.4.1]

509.3.2 Appliance Venting Requirements

Appliances required to be vented shall be connected to a venting system designed and installed in accordance with the provisions of Section 509.4 through Section 509.15. [NFPA 54:12.4.2]

509.3.3 Mechanical Draft Systems

Mechanical draft systems shall be listed and installed in accordance with both the appliance and the mechanical draft system manufacturer’s installation instructions. [NFPA 54:12.4.3.1]

509.3.3.1 Venting

Appliances requiring venting shall be permitted to be vented by means of mechanical draft systems of either forced or induced draft design. [NFPA 54:12.4.3.2]

509.3.3.2 Leakage

Forced draft systems and portions of induced draft systems under positive pressure during operation shall be designed and installed so as to prevent leakage of flue or vent gases into a building. [NFPA 54:12.4.3.3]

509.3.3.3 Vent Connectors

Vent connectors serving appliances vented by natural draft shall not be connected into any portion of mechanical draft systems operating under positive pressure. [NFPA 54:12.4.3.4]

509.3.3.4 Operation

Where a mechanical draft system is employed, provision shall be made to prevent the flow of gas to the main burners where the draft system is not performing so as to satisfy the operating requirements of the appliance for safe performance. [NFPA 54:12.4.3.5]

509.3.3.5 Exit Terminals

The exit terminals of mechanical draft systems shall be not less than 7 feet (2134 mm) above finished ground level where located adjacent to public walkways and shall be located as specified in Section 509.8 and Section 509.8.1 of this code. [NFPA 54:12.4.3.6]

509.3.4 Ventilating Hoods and Exhaust Systems

Ventilating hoods and exhaust systems shall be permitted to be used to vent appliances installed in commercial applications. [NFPA 54:12.4.4.1]

509.3.4.1 Automatically Operated Appliances

Where automatically operated appliances, other than commercial cooking appliances, are vented through a ventilating hood or exhaust system equipped with a damper or with a power means of exhaust, provisions shall be made to allow the flow of gas to the main burners where the damper is open to a position to properly vent the appliance and where the power means of exhaust is in operation. [NFPA 54:12.4.4.2]

509.3.5 Circulating Air Ducts and Furnace Plenums

Venting systems shall not extend into or pass through a fabricated air duct or furnace plenum. [NFPA 54:12.4.5.1]

509.3.6 Above-Ceiling or Nonducted Air Handling System

Where a venting system passes through an above-ceiling air space or other nonducted portion of an air-handling system, it shall conform to one of the following requirements:

The venting system shall be a listed special gas vent, other system serving a Category III or Category IV appliance, or other positive pressure vent, with joints sealed in accordance with the appliance or vent manufacturer’s instructions.

The vent system shall be installed such that no fittings or joints between sections are installed in the above-ceiling space.

The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2]

509.4 Type of Venting System to Be Used

The type of venting system to be used shall be in accordance with Table 509.4. [NFPA 54:12.5.1]

VENTED APPLIANCE CATEGORIES. Appliances that are categorized for the purpose of vent selection are classified into the following four categories:

Category I. An appliance that operates with a nonpositive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.                       No condensation. Negative air

Category II. An appliance that operates with a nonpositive vent static pressure and with a vent gas temperature that is capable of causing excessive condensate production in the vent.

 This Category does not have any equipment listed.

Category III. An appliance that operates with a positive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.

Fan pushes the air…. Pipes are positive

Category IV. An appliance that operates with a positive vent static pressure and with a vent gas temperature that is capable of causing excessive condensate production in the vent.

Positive pressure. Condensation.

Back to Plumbing Code…

CPVC is used for higher operating temperatures than PVC. Be sure to follow manufacturer instructions to ensure quality sealed joints.

509.4.1 Plastic Piping

Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufacturer’s installation instruction shall identify the specific plastic piping material. [NFPA 54:12.5.2]

509.4.2 Plastic Vent Joints

Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Where primer is required, it shall be of a contrasting color. [NFPA 54:12.5.3]

509.4.3 Special Gas Vents

Special gas vents shall be listed and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4]

Operating Temperatures are Key

Whether your furnace is vented with metal or plastic depends on its operating temperature, which is related to the fuel being used. For example, wood and oil burn at very high temperatures, with flames reaching roughly 1100°F and the flue gas temperature (chimney temperature) ranging from 400° to 900° F when burning wood and between 350° and 500° F when burning oil.

Gas burns at different temperatures depending on the type of furnace and its efficiency. An older furnace that runs between 65 and 82% efficiency burns between 275° and 350° F. That’s lower than wood or oil, but still hot enough to require metal venting.

Newer, higher efficiency furnaces, run much cooler. A furnace running at 90 to 98% efficiency burns at only 85° to 150° F. When these furnaces burn gas, they form a liquid and mild acid condensate (so they are called condensing furnaces). Not only do these high-efficiency models not need a metal vent due to their low burning temperature, but a metal flue would actually rust over time due to the mild acid that’s formed. As a result, the vent of a high-efficiency furnace needs to be corrosion resistant and liquid tight. Plastic — typically PVC or CPVC — is perfect. It would be possible to use high-quality stainless steel, however, that’s very expensive, so it is rarely used.

Types of Venting

A conventional brick or metal chimney relies on the buoyancy of the warm flue gasses to move the gasses up and out. Because the warm air rising only works if it can rise, it needs a vertical vent. This type of chimney is sometimes called “natural venting” or “gravity venting.”

By contrast, new furnaces have an electric-powered blower that pushes the flue gasses out. These go by several names — draft fan, draft blower, draft inducer, or inducer blower. The blower makes it possible to vent out the side of a house — sidewall venting or horizontal venting.

One advantage to the old-style venting system is that multiple appliances can be combined on the same vent. So, the water heater can be vented with the furnace, for example. In some cases, there could be three or four appliances using the same vent, as long as they all work with natural venting. The new PVC venting systems have to follow strict code and manufacturer guidelines and cannot be used for multiple appliances; each has to have its own vent.

An Easy Way to Know Your Furnace’s Efficiency

Whether you have a metal or plastic vent is a simple way to determine the efficiency of your current furnace. If it’s metal, you know you’re running in that 65-80% range. If that’s the case, it may be time to consider replacing your system with a new, more efficient unit. There are many options available, and over a short period of time, you can recoup the cost of a new system with the energy savings you’ll get in exchange.

Of course, if you’ve got a plastic vent, you can rest assured that your furnace is running in that high-efficiency range of 90% or more. Congratulations!

Baseline Temperature/Upper Limit

Standardized reference points for all published PVC dimensions usually apply to a temperature of 73 degrees F. Colder temperatures typically do not affect PVC piping’s strength, but as PVC piping gets warmer, it becomes more pliable and less able to hold pressurized fluid. The precise upper temperature limit can vary slightly depending on the exact specifications of the PVC pipe. However, generally speaking, the upper limit of PVC pipes is 140 degrees F; beyond that temperature, the PVC piping is at risk of losing its structural integrity.

Temperature Effect on PVC Dimensions

Temperature changes can cause slight variations of the dimensions of PVC piping, most notably in the length of the pipe. Generally speaking, you can expect a change of approximately 3/8-inch in length per every 100 feet of piping for every 10 degree F temperature change; this rule is typical of all PVC piping regardless of diameter. This phenomenon occurs both with increases in temperature, from the baseline temperature, and with decreases in temperature.

Temperature Effect on Pressure Capacity

The pressure capacity of the PVC diminishes from the baseline of 73 degrees as the temperature increases. To determine the diminished pressure capacity, you should use the following numbers: at 80 degrees, multiply the baseline pressure by .88, at 90 by .75, 100 by .62, 110 by .52, 120 by .40, 130 by .30, and 140 by .22. For example, if the PVC pipe has a baseline pressure capacity of 400 PSI at 73 degrees Fahrenheit, then the pressure at 110 degrees would be produced using the formula 400 x .50 = 200; your new pressure capacity is 200 PSI. Decreasing temperatures do not adversely affect the baseline pressure capacity of the pipes; for temperatures below 73 degrees F, you should refer to the published baseline pressure capacity.

Temperature Effect on Pipe Stiffness

The pressure capacity of the PVC diminishes from the baseline of 73 degrees as the temperature increases. To determine the diminished pressure capacity, you should use the following numbers: at 80 degrees, multiply the baseline pressure by .88, at 90 by .75, 100 by .62, 110 by .52, 120 by .40, 130 by .30, and 140 by .22. For example, if the PVC pipe has a baseline pressure capacity of 400 PSI at 73 degrees Fahrenheit, then the pressure at 110 degrees would be produced using the formula 400 x .50 = 200; your new pressure capacity is 200 PSI. Decreasing temperatures do not adversely affect the baseline pressure capacity of the pipes. For temperatures below 73 degrees F, you should refer to the published baseline pressure capacity.

Pressure derating of the fittings that results when the operational temperature of the pipe or fittings changes.

Maximum Short Time Operating Temperature

– for pipes without pressure.

• PVC : 95 ^oC-203 F
• PP : 100 ^oC- 212 F
• PE : 95 ^oC

Heat Distortion Temperature

– is the temperature where a test piece of a material placed in a heat medium with a bending load (18.6 kg/cm²) applied – reaches a specified deflection.

• ABS: 104 – 106 ^oC  2192F
• PVC: 54 – 80 ^oC 129.2-176 F
• HDPE: 43 – 49 ^oC
• LDPE: 32 – 41 ^oC
• PP: 57 – 64 ^oC

Vicat Softening Temperature

– is the temperature where a needle shaped penetrator sinks into a test piece a specified depth when a specified vertical load (1 kg) is applied.

• ABS: 102.3 ^oC
• PVC: 92 ^oC
• PE: 127.3 ^oC
• PP: 152.2 ^oC

One of the critical concerns of my use of plastics within building structures is the following graph, release of toxic fumes within building when released in he building.

Polymer + Heat -> Thermal Decomposition Products Decomposition Products + Oxygenated Radicals-> Combustion Products + Heat

The maximum operating temperature for PVC pressure pipe is 140°F.

PVC pipe and conduit becomes stiffer with decreasing temperature and more flexible with   increasing temperature. As with dimensions and pressure    capacity, published pipe stiffness figures are applicable only for 73°F operating temperatures.

On a practical level, heating PVC pipe can cause distortion. With a melting point of about 176 degrees Fahrenheit, PVC pipes may bend as the material approaches this temperature. Active PVC pipes should never be heated beyond 158 degrees.

PVC is resistant to ignition. The temperature required to ignite rigid PVC is more than 150 C (302 F) higher than that required to ignite wood.

Aging of plastic through time or heat: Plastic undergoes through process where Thermoplast becomes Thermoset.

Water Heater Structure- Note flue piping specified

Following are from Ron George Article:

As stated in the International Code Council’s International Fuel Gas Code 503.4.1.1:
Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions.

Furthermore, several of the ASTM standards applicable to PVC plastic pipe and fittings that this company manufactures their pipe to include the following note: This standard specification for PVC pipe does not include requirements for pipe and fittings intended to be used to vent combustion gases.

There is no standard referenced in any of the codes in the United States for a plastic flue vent for combustion flue gas piping, although many water heater and boiler manufacturers recommend this.

There is a Canadian standard, ULC S636, but that standard has several flaws in that it allows flue gas temperatures that exceed the temperature limits of the pipe material manufacturers.

The maximum temperatures listed in the ABS, PVC and CPVC pipe manufacturers’ technical literature are shown in the following table. Any temperatures above the rated temperature will allow the pipe to melt, sag and, possibly, collapse or pull apart. There are serious consequences with carbon monoxide asphyxiation and fire that cannot be ignored.

Generally, for a new condensing water heater or boiler, the stack temperature will be about 20 degrees higher than the water temperature. The design and efficiency of the unit, along with several other factors, including water quality, will affect the stack temperature. If a water heater is set to store water at 140 F to minimize Legionella bacteria growth, the flue gas temperature will be about 160 F when the heater is new.

As scale builds up and the heater efficiency falls off, the flue gas temperatures can easily increase to over 350 degrees F. Even if someone had their water heater set at 120 F, with scaling, the flue gas temperatures can rise well above 300 F. Boiler thermostats or burner controls are generally limited to 200 F, commercial water heater thermostats or burner controls to 180 F and residential water heater burner controls to 160 F, and all can overshoot by several degrees. As scale builds up on the heating surfaces, the scale insulates the flue gases from the hot water in the system, causing the flue gas temperatures to increase.

Some boiler and water heater manufacturers offer stack or flue gas temperature gauges as a way to see whether the unit is scaling up and losing efficiency, which is helpful for monitoring the flue condition. A temperature sensor or probe with a high-limit control could be inserted into the flue at the flue connection to the boiler or water heater.

This control would shut off the burner if the flue gas temperature exceeds the temperature rating of the flue pipe.

A standard will be needed for plastic flue pipes that should include a temperature gauge and a high limit probe. Then PVC, CPVC and polypropylene flue gas piping can be safely used on high efficiency boilers and water heaters. This would be an answer to the dilemma of cost versus safety

Without a standard for proper use of these safety devices in combination with plastic flue gas piping or without the use of stainless steel flues, plastic flue materials can melt as flue gas temperatures rise. Not only is energy lost when this happens but flues can become blocked or disconnected, which can be a carbon monoxide or a fire danger.

A family of four died in Aspen, Colorado, in 2008, of carbon monoxide poisoning from the failure of PVC plastic flue pipes on a condensing snow melting boiler system in a rental property. The plastic pipe manufacturer was not at fault, because they had published limitations on the use of their piping, and they had not recommended PVC piping for that application. The boiler manufacturer that recommended using PVC pipe as flue material was a target of the liability claim by surviving family members.

The Canadian standard, ULC S636, covers the design, construction and performance of gas venting systems intended for negative or positive pressure venting of gas-fired appliances producing flue gases having temperatures under the following:

1. Class I venting systems are suitable for gas-fired appliances producing flue gas temperatures of more than 135 C (275 F) but not more than 245 C (473 F);
2. Class II venting systems are suitable for gas-fired appliances producing flue gas temperatures of 135 C (275 F) or less;
3. Class II venting systems are further classified into four temperature ratings as follows:
   (A) Up to and including 65 C (149 F)

This temperature limit was intended to allow the use of PVC pipe for use as a flue gas material. The temperature limit for PVC pipe is 140 F, and the allowable temperature in the ULC S636 standard exceeds the temperature limits set by PVC pipe manufacturers.

(B) Up to and including 90 C (190 F)

This temperature limit was intended to allow the use of CPVC pipe for use as a flue gas material. The temperature in the pipe manufacturer technical data is 180 F. The ULC S636 standard allows the material to exceed the limit for CPVC piping by 10 degrees Fahrenheit.

(C) Up to and including 110 C (230 F)

This temperature limit was intended to allow the use of Polypropylene (PP) pipe for use as a flue gas material. There is currently one manufacturer listed to this standard, but the potential for the flue gases to exceed the 230 F is still there. A high-limit switch to shut off the boiler or water heater would be advisable.

(D) Up to and including 135 C (275 F)

I am not aware of any plastic pipe manufacturers that meet this sub-section of the standard. The potential for the flue gas temperatures to exceed the 230 F is still there. A high-limit switch to shut off the boiler or water heater would be advisable.

The final Irony: PVC manufacturer does not want to take the liability of use of their plastic piping in the venting…….

One of the PVC piping manufacturer’s technical manuals has the following information:
Using Plastics for Combustion Gas Venting
The piping manufacturer recommends that inquiries about the suitability of plastic piping systems for venting combustion gasses should be directed to the manufacturer of the water or space heating equipment being installed.
As stated in the International Code Council’s International Fuel Gas Code 503.4.1.1:
Plastic Pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions.
Furthermore, several of the ASTM standards applicable to PVC plastic pipe and fittings that this manufacturer, manufacture’s their pipe to include the following note:
This standard specification for PVC pipe does not include requirements for pipe and fittings intended to be used to vent combustion gases.

April 23rd, 2021

Dr. Saum K. Nour

This was Presented at the ASHRAE Spring Conference April 23rd, 2021, southern California Chapter through Zoom.

As first panelist to speak on theory and basics of Covid 19 virus for Indoor Ventilation Design, I relied on all historical challenges that the scientists, and engineers were to tackle the past pandemics.

Recent Memories of Diseases or outbreaks:

HIV infections, SARS, Lyme disease, Escherichia coli O157:H7 (E. coli), hantavirus, dengue fever, West Nile virus, and the Zika virus.

Re-emerging diseases:

malaria, tuberculosis, cholera, pertussis, influenza, pneumococcal disease, and gonorrhea.

All restroom sensors driven fixtures were pushed through recent pandemics.

Also, in history:

Paris: Haussmann’s renovation of Paris was a vast public works program commissioned by Emperor Napoléon III and directed by his prefect of Seine, Georges-Eugène Haussmann, between 1853 and 1870. It included the demolition of medieval neighborhoods that were deemed overcrowded and unhealthy by officials at the time; the building of wide avenues; new parks and squares; the annexation of the suburbs surrounding Paris; and the construction of new sewers, fountains and aqueducts. Haussmann’s work was met with fierce opposition, and he was finally dismissed by Napoleon III in 1870; but work on his projects continued until 1927. The street plan and distinctive appearance of the center of Paris today are largely the result of Haussmann’s renovation.

London: The Broad Street cholera outbreak (or Golden Square outbreak) was a  Severe outbreak of cholera that occurred in 1854 near Broad Street (now Broadwick Street) in the Soho district of the City of Westminster, London, England, and occurred during the 1846–1860 cholera pandemic happening worldwide. This outbreak, which killed 616 people, is best known for the physician John Snow‘s study of its causes and his hypothesis that germ-contaminated water was the source of cholera, rather than particles in the air (referred to as “miasma“).^[1][2] This discovery came to influence public health and the construction of improved sanitation facilities beginning in the mid-19th century. Later, the term “focus of infection” started to be used to describe sites, such as the Broad Street pump, in which conditions are good for transmission of an infection. Snow’s endeavor to find the cause of the transmission of cholera caused him to unknowingly create a double-blind experiment.

New York City in the late 1800s faced grim, cramped living conditions in tenement housing that once dominated the Lower East Side. During the 19th century, immigration steadily increased, causing New York City’s population to double every decade from 1800 to 1880.

Walls were erected to create extra rooms, floors were added, and housing spread into backyard areas. To keep up with the population increase, construction was done hastily, and corners were cut. Tenement buildings were constructed with cheap materials, had little or no indoor plumbing and lacked proper ventilation. These cramped and often unsafe quarters left many vulnerable to rapidly spreading illnesses and disasters like fires.

By 1900, more than 80,000 tenements had been built and housed 2.3 million people, two-thirds of the total city population.

Purpose or thesis of the topic:

A New Normal has to be defined, once everyone is vaccinated or reach “Herd Immunity” ~80-85% of population. However, building indoor environment must be ready to accept the population.  We are not done.

Unfortunately:

There is not a unified, uniform, method at this time.

CDC under Implement Engineering Controls mandates:

Design and install engineering controls to reduce or eliminate exposures …. Examples of engineering controls include:

• physical barriers or partitions to guide patients through triage areas
• curtains between patients personnel in shared areas

air-handling systems (with appropriate directionality, filtration, exchange rate, etc.) that are properly installed and maintained.

Engineer’s Mission Statement

Engineers must create new design and new thinking process for indoor environmental safety of occupants. Engineers’ design must provide confidence for general public to go back to their daily life..

This will be today and tomorrows’ Engineer’s task.

What does the battle look like?

https://www.facebook.com/What.If.science/videos/what-happens-in-your-body-if-you-caught-the-coronavirus/623759241800631/

• Virus leaches to existing living cells of body, kills and multiples.
• Covid 19- A 0.12-micron Novel virus (Unknown) identified in 2019.
• A very highly efficient respiratory infectious virus.

                        116 days

• UK Strand now is the predominant version. Higher efficacy of infection. 3x
• South African is even higher. 7x
• Now US has their own brand as well.
• How long is the Vaccine good for min 6 months?
• 75% Vaccines are for 14% countries.
• Till world is secure we are not.
• Still near 100,000 daily cases. 4 22 2021

Please read the entire manuscript attached below.

http://greenerade.com/wp-content/uploads/2021/06/Saum-Nour-ASHRAE-Spring-conference-Spring-2021on-Covid-19.pdf

Greetings,

This is the lecture provided for AIA OC- December 5th and December 12th, 2018.

Since then, unbelievable level of rain, impact of Woolsey (ironically I was stuck in Thousand Oaks all night due to fire), all new upcoming mandatory codes are emerging into one basket.

The recent rainfall has not made a major impact on the California drought condition.

This is an Architects Be-Aware Document.

Dec 5th 2018 AIA OC Part I- a

Dec 5th 2018 AIA OC Part I- b

Dec 12th 2018 AIA OC Part II- a

Dec 12th 2018 AIA OC Part II- b

1. I am simply tired of making energy crisis, fire crisis, and water crisis a political issue.
2. Farmers in the rural areas with affinity to one group or another cannot plant the seed they wish.
3. The Urban dwellers with other political affinity take shower, as if there are endless supply of water.

Be aware and design your buildings accordingly and please, I beg you have your large surface roofs face the south for the solar panels.

Every drop counts.

Saum