Tag Archives: Summer

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Rain & Lightning

After the rain. Personal photograph taken by Mike Anthony biking with his niece in Wirdum, The Netherlands

Today at 15:00 UTC we examine the technical literature about rainwater management in schools, colleges and universities — underfoot and on the roof.  Lightning protection standards will also be reviewed; given the exposure of outdoor athletic activity and exterior luminaires.

We draw from previous standardization work in titles involving water, roofing systems and flood management — i.e. a cross-cutting view of the relevant standard developer catalogs.   Among them:

American Society of Civil Engineers

American Society of Plumbing Engineers

ASHRAE International

ASTM International

Construction Specifications Institute (Division 7 Thermal and Moisture Protection)

Environmental Protection Agency | Clean Water Act Section 402

Federal Emergency Management Agency

FM Global

Sustainable Sites Initiative

IAPMO Group (Mechanical and Plumbing codes)

Institute of Electrical and Electronic Engineers

Heat Tracing Standards

International Code Council

Chapter 15 Roof Assemblies and Rooftop Structures

Why, When, What and Where Lightning Protection is Required

National Fire Protection Association

National Electrical Code: Article 250.16 Lightning Protection Systems

Lightning Protection

Underwriters Laboratories: Lightning Protection

Underground Stormwater Detention Vaults

United States Department of Agriculture: Storm Rainfall Depth and Distribution

Risk Assessment of Rooftop-Mounted Solar PV Systems

Readings: The “30-30” Rule for Outdoor Athletic Events Lightning Hazard

As always, our daily colloquia are open to everyone.  Use the login credentials at the upper right of our home page.

“Rainbow Connection”

The “lightning effect” seen in carnival tricks typically relies on a scientific principle known as the Lichtenberg figure or Lichtenberg figure. This phenomenon occurs when a high-voltage electrical discharge passes through an insulating material, such as wood or acrylic, leaving behind branching patterns resembling lightning bolts.

The process involves the creation of a temporary electric field within the material, which polarizes its molecules. As the discharge propagates through the material, it causes localized breakdowns, creating branching paths along the way. These branching patterns are the characteristic Lichtenberg figures.

In the carnival trick, a high-voltage generator is used to create an electrical discharge on a piece of insulating material, such as acrylic. When a person touches the material or a conductive object placed on it, the discharge follows the path of least resistance, leaving behind the branching patterns. This effect is often used for entertainment purposes due to its visually striking appearance, resembling miniature lightning bolts frozen in the material. However, it’s crucial to handle such demonstrations with caution due to the potential hazards associated with high-voltage electricity.

 

Lightning Protection Systems

“Benjamin Franklin Drawing Electricity from the Sky” 1816 Benjamin West

 

Benjamin Franklin conducted his famous experiment with lightning on June 10, 1752.

He used a kite and a key to demonstrate that lightning was a form of electricity.

This experiment marked an important milestone in understanding the nature of electricity

and laid the foundation for the development of lightning rods and other lightning protection systems.

 

Seasonal extreme weather patterns in the United States, resulting in damages to education facilities and delays in outdoor athletic events — track meets; lacrosse games, swimming pool closures and the like — inspire a revisit of the relevant standards for the systems that contribute to safety from injury and physical damage to buildings: NFPA 780 Standard for the Installation of Lightning Protection Systems

FREE ACCESS

To paraphrase the NFPA 780 prospectus:

  • This document shall cover traditional lightning protection system installation requirements for the following:
       (1) Ordinary structures

       (2) Miscellaneous structures and special occupancies
       (3) Heavy-duty stacks
       (4) Structures containing flammable vapors, flammable gases, or liquids with flammable vapors
       (5) Structures housing explosive materials
       (6) Wind turbines
       (7) Watercraft
       (8) Airfield lighting circuits
       (9) Solar arrays
  • This document shall address lightning protection of the structure but not the equipment or installation requirements for electric generating, transmission, and distribution systems except as given in Chapter 9 and Chapter 12.

(Electric generating facilities whose primary purpose is to generate electric power are excluded from this standard with regard to generation, transmission, and distribution of power.  Most electrical utilities have standards covering the protection of their facilities and equipment. Installations not directly related to those areas and structures housing such installations can be protected against lightning by the provisions of this standard.)

  • This document shall not cover lightning protection system installation requirements for early streamer emission systems or charge dissipation systems.

“Down conductors” must be at least #2 AWG copper (0 AWG aluminum) for Class I materials in structures less than 75-ft in height

“Down conductors: must be at least 00 AWG copper (0000 AWG aluminum) for Class II Materials in structures greater than 75-ft in height.

Related grounding and bonding  requirements appears in Chapters 2 and Chapter 3 of NFPA 70 National Electrical Code.  This standard does not establish evacuation criteria.  

University of Michigan | Washtenaw County (Photo by Kai Petainen)

The current edition is dated 2023 and, from the transcripts, you can observe concern about solar power and early emission streamer technologies tracking through the committee decision making.  Education communities have significant activity in wide-open spaces; hence our attention to technical specifics.

2023 Public Input Report

2023 Public Comment Report

Public input on the 2026 revision is receivable until 1 June 2023.

We always encourage our colleagues to key in their own ideas into the NFPA public input facility (CLICK HERE).   We maintain NFPA 780 on our Power colloquia which collaborates with IEEE four times monthly in European and American time zones.  See our CALENDAR for the next online meeting; open to everyone.

Lightning flash density – 12 hourly averages over the year (NASA OTD/LIS) This shows that lightning is much more frequent in summer than in winter, and from noon to midnight compared to midnight to noon.

Issue: [14-105]

Category: Electrical, Telecommunication, Public Safety, Risk Management

Colleagues: Mike Anthony, Jim Harvey, Kane Howard


More

Installing lightning protection system for your facility in 3 Steps (Surge Protection)

IEEE Education & Healthcare Facility Electrotechnology

Readings: The “30-30” Rule for Outdoor Athletic Events Lightning Hazard

Churches and chapels are more susceptible to lightning damage due to their height and design. Consider:

Height: Taller structures are more likely to be struck by lightning because they are closer to the cloud base where lightning originates.

Location: If a church or chapel is situated in an area with frequent thunderstorms, it will have a higher likelihood of being struck by lightning.

Construction Materials: The materials used in the construction of the building can affect its vulnerability. Metal structures, for instance, can conduct lightning strikes more readily than non-metallic materials.

Proximity to Other Structures: If the church or chapel is located near other taller structures like trees, utility poles, or buildings, it could increase the chances of lightning seeking a path through these objects before reaching the building.

Lightning Protection Systems: Installing lightning rods and other lightning protection systems can help to divert lightning strikes away from the structure, reducing the risk of damage.

Maintenance: Regular maintenance of lightning protection systems is essential to ensure their effectiveness. Neglecting maintenance could result in increased susceptibility to lightning damage.

Historical Significance: Older buildings might lack modern lightning protection systems, making them more vulnerable to lightning strikes.

The risk can be mitigated by proper design, installation of lightning protection systems, and regular maintenance. 

Virginia Tech

The Eternal Music

“Heard melodies are sweet,
but those unheard are sweeter…”
John Keates (Ode on a Grecian Urn)

Click image

Lively Arts 300

 

Annabelle Hydrangea

Summer Week 25 | June 17 – June 23

 


Monday | 17 June | Colloquium 15:00 UTC

Salutariness


Tuesday | 18 June | Colloquium 15:00 UTC

Reliability


Wednesday | 19 June | Colloquium 15:00 UTC

print (“Hello World!”)


Thursday | 20 June | Colloquium 15:00 UTC

Planetariums


Friday | 21 June | Colloquium 15:00 UTC

Nourriture de printemps


Saturday | 22 June


Sunday | 23 June


Readings: The “30-30” Rule for Outdoor Athletic Events Lightning Hazard

Thunderstorm | Shelter (Building: 30/30 Rule)

The standards for delaying outdoor sports due to lightning are typically set by governing bodies such as sports leagues, associations, or organizations, as well as local weather authorities. These standards may vary depending on the specific sport, location, and level of play. However, some common guidelines for delaying outdoor sports due to lightning include:

  1. Lightning Detection Systems: Many sports facilities are equipped with lightning detection systems that can track lightning activity in the area. These systems use sensors to detect lightning strikes and provide real-time information on the proximity and severity of the lightning threat. When lightning is detected within a certain radius of the sports facility, it can trigger a delay or suspension of outdoor sports activities.
  2. Lightning Distance and Time Rules: A common rule of thumb used in outdoor sports is the “30-30” rule, which states that if the time between seeing lightning and hearing thunder is less than 30 seconds, outdoor activities should be suspended, and participants should seek shelter. The idea is that lightning can strike even when it is not raining, and thunder can indicate the proximity of lightning. Once the thunder is heard within 30 seconds of seeing lightning, the delay or suspension should be implemented.
  3. Local Weather Authority Guidelines: Local weather authorities, such as the National Weather Service in the United States, may issue severe weather warnings that include lightning information. Sports organizations may follow these guidelines and suspend outdoor sports activities when severe weather warnings, including lightning, are issued for the area.
  4. Sports-Specific Guidelines: Some sports may have specific guidelines for lightning delays or suspensions. For example, golf often follows a “Play Suspended” policy, where play is halted immediately when a siren or horn is sounded, and players are required to leave the course and seek shelter. Other sports may have specific rules regarding how long a delay should last, how players should be informed, and when play can resume.

It’s important to note that safety should always be the top priority when it comes to lightning and outdoor sports. Following established guidelines and seeking shelter when lightning is detected or severe weather warnings are issued can help protect participants from the dangers of lightning strikes.

Noteworthy: NFPA titles such as NFPA 780 and NFPA 70 Article 242 deal largely with wiring safety, informed by assuring a low-resistance path to earth (ground)

There are various lightning detection and monitoring devices available on the market that can help you stay safe during thunderstorms. Some of these devices can track the distance of lightning strikes and alert you when lightning is detected within a certain radius of your location. Some devices can also provide real-time updates on lightning strikes in your area, allowing you to make informed decisions about when to seek shelter.

Examples of such devices include personal lightning detectors, lightning alert systems, and weather stations that have lightning detection capabilities. It is important to note that these devices should not be solely relied upon for lightning safety and should be used in conjunction with other safety measures, such as seeking shelter indoors and avoiding open areas during thunderstorms.

Occupant-Based HVAC Thermal Setpoints

Occupant-based HVAC Set Point Interventions for Energy Savings in Buildings

Dimas Ardiyanto
PT PLN (Persero), Jakarta, Indonesia
Manisa Pipattanasomporn & Saifur Rahman
Virginia Tech – Advanced Research Institute, Arlington, VA, USA
Nanang Hariyanto & Suwarno
School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Indonesia

 

Abstract:  Energy savings and occupant thermal comfort are the two most important factors in controlling heating ventilation and air conditioning (HVAC) operation in buildings. Typically, it is found that thermal comfort is not always met in buildings. Hence, there is still an opportunity to improve indoor thermal comfort, and at the same time save energy by controlling HVAC set points. The objective of this paper is to propose a method to obtain energy savings by adjusting HVAC set points based on occupant comfort measured using Predicted Mean Vote (PMV) and occupancy information. The idea is to calculate hourly PMV values based on real-time occupancy information, indoor temperature set points and humidity in a building. Then, a new set of temperature set points that can maintain occupant comfort, i.e., PMV = 0, is derived. To evaluate the effectiveness of the proposed method, a building model is developed in eQUEST using the information from a real-world building located in Alexandria, VA. Research findings indicate that HVAC electrical consumption savings of 14.58% is achieved when the proposed set point adjustment method is implemented as compared to that of the base case. To study the impact of adding occupancy information on HVAC energy savings, another scenario is simulated where HVAC set point is increased when the building is unoccupied, e.g., during lunchtime or holidays. Research findings indicate that additional HVAC electrical consumption savings of 8.79% is achieved when taking into account occupancy information in HVAC control.

 

Document Sections
I. Introduction
II. PMV as an Index for Thermal Comfort
III. Experiment Set Up To Capture Occupancy Information
IV. Building Model Development in Equest
V. Energy Savings From Comfort Adjustment And Occupancy Information

CLICK HERE for ordering Information for this article

DRINKING, WASTEWATER & STORMWATER SYSTEMS

“Fille romaine à la fontaine” 1875 Léon Bonnat

Civilization has historically flourished around rivers and major waterways.  Mesopotamia, the so-called cradle of civilization, was situated between the major rivers Tigris and Euphrates; the ancient society of the Egyptians depended entirely upon the Nile. Rome was also founded on the banks of the Italian river Tiber. Large metropolises like Rotterdam, London, Montreal, Paris, New York City, Buenos Aires, Shanghai, Tokyo, Chicago, and Hong Kong owe their success in part to their easy accessibility via water and the resultant expansion of trade. Islands with safe water ports, like Singapore, have flourished for the same reason. In places such as North Africa and the Middle East, where water is more scarce, access to clean drinking water was and is a major factor in human development.*

With this perspective, and our own “home waters” situated in the Great Lakes, we are attentive to water management standardization activity administered by International Organization Standardization Technical Committee 224 (ISO TC/224).  The scope of the committee is multidimensional; as described in the business plan linked below:

BUSINESS PLAN ISO/TC 224

 

Water-related management standards define a very active space; arguably, as fast-moving a space as electrotechnology.   The ISO TC/224 is a fairly well accomplished committee with at least 16 consensus products emerging from a 34 nations led by Association Française de Normalisation (@AFNOR) as the global Secretariat and 34 participating nations.   The American Water Works Association is ANSI’s US Technical Advisory Group administrator to the ISO.

We do not advocate the user interest in this standard at the moment but encourage educational institutions with resident expertise — either on the business side or academic side of US educational institutions — to participate in it.   You are encouraged to communicate directly with Paul Olson at AWWA, 6666 W. Quincy Avenue, Denver, CO 80235, Phone: (303) 347-6178, Email: [email protected].

The work products of TC 224 (and ISO 147 and  ISO TC 282) are also on the standing agendas of our Water, Global and Bucolia colloquia.  See our CALENDAR for the next online meeting, open to everyone.

Issue: [13-163]

Category: Global, Water

Colleagues: Mike Anthony, Christine Fischer, Jack Janveja. Richard Robben, Larry Spielvogel

Standing Agenda / Water


Qualität der Wasserversorgung

Bucolia 100

I will arise and go now, and go to Innisfree,
And a small cabin build there, of clay and wattles made;
Nine bean-rows will I have there, a hive for the honey-bee,
And live alone in the bee-loud glade.
And I shall have some peace there, for peace comes dropping slow,
Dropping from the veils of the morning to where the cricket sings;
There midnight’s all a glimmer, and noon a purple glow,
And evening full of the linnet’s wings.
I will arise and go now, for always night and day
I hear lake water lapping with low sounds by the shore;
While I stand on the roadway, or on the pavements grey,

I hear it in the deep heart’s core.

— William Butler Yeats

Anglo-americká vysoká škola, z.ú. Czech Republic

Today we walk through literature governing the safety and sustainability of the open space features of education community estates.   Unlike the titles for the building envelope, which are known to most design professionals and contractors, the standards for grounds and landscaping are widely scattered; many of them occupational safety related; created, administered and enforced by units of government.

Bucolia 100.  We present a broad overview of the dominant standards catalogs incorporated by reference into public safety and sustainability legislation.

Bucolia 200.  We drill into technical specifics of the titles in Bucolia 100.

Bucolia 400.  We pick through case studies in landscape, garden, tree and water literature.  We also track titles about the reclamation of building roofs for permeable surfaces and gardens.

During the winter months (Bucolia 200) in the northern hemisphere we include snow and ice management; while covering summer month technologies for southern hemisphere (and vice-versa).  Snowfalls in the southern hemisphere are mainly contained to the highlands and mountain ranges, which are almost exclusively in Victoria and Southern New South Wales, as well as the mountains in Tasmania.   Winter does not pose as much of a cost burden to education facilities in the southern hemisphere as it does in the northern hemisphere.

Arboreta

Landscape standards refer to guidelines or regulations that specify the requirements for the design, installation, and maintenance of outdoor spaces such as parks, gardens, streetscapes, and public spaces. Landscape standards typically cover various aspects of landscape design, including vegetation selection, planting arrangements, irrigation systems, hardscape materials, and lighting.

These standards may be set by government agencies at the federal, state, or local level, or by professional organizations such as the American Society of Landscape Architects (ASLA). Landscape standards aim to ensure that outdoor spaces are safe, functional, and aesthetically pleasing while also promoting sustainability and environmental protection.

Landscape standards may also address issues such as accessibility for people with disabilities, water conservation, stormwater management, and erosion control. They may vary depending on the specific location, climate, and intended use of the outdoor space. Compliance with landscape standards may be required for approval of development projects, public funding, or other permits.

We track the standards catalog of two ANSI-accredited standards developers:

American Hort

Tree Care Industry Association

Additional practice titles applicable to accessory systems:

ASABE/ICC 802 Landscape Irrigation Sprinkler and Emitter Standard 

ASHRAE 90.1 Energy Standard for Sites and Buildings

Golf Course Superintendents Association of America

National Electrical Code: Article 411 Low-Voltage Lighting

Upcode Article 411

National Electrical Code: Article 225: Outside Branch Circuits and Feeders

Illumination Engineering Society (Lighting Library)

IoT Enabled Smart Gardening

Land F/X: Landscape Lighting, Codes, Guidelines and Techniques  

OSHA Landscape and Horticultural Services

Sports Turf Managers Association

As a cross-cutting subjectSports Turf Managers Association ( involving soil and water and sun many other standards developers, and all levels of government, produce best practice literature for today’s topic.  We’ll have a look at what’s moving among those.

To join us use the login credentials at the upper right of our home page.

Keeping Soil Alive

Lightning protection techniques for roof-top PV systems

Lightning protection techniques for roof-top PV systems

Narjes Fallah, et. al

Centre for Electromagnetic and Lightning Protection Research (CELP), Electrical & Electronic Engineering Department, Universiti Putra Malaysia, Malaysia

ABSTRACT: In this paper, the lightning protection requirements of a typical residential building have been discussed and techniques have been provided to protect the building from both direct and indirect damages of lightning, with special attention to the protection of PV panels placed on the roof. These techniques include the designing challenges and also the type of devices which can be used to reduce the surge current flow and magnetic field. It has been shown that for buildings with roof top PV systems only the avoidance of lightning attachment to unprotected parts of the building is not sufficient. Lightning currents passing through the lightning protection system may still affect the PV power system through inductive coupling. Hence strategic placement of PV systems and shielding of conducting systems wherever possible has been recommended. It has also been envisaged that the impact of lightning on PV systems is directly related to the isokeraunic level of the region and elevation of the building. Several recommendations have been proposed in designing the air termination system for a roof with PV panels in high isokeraunic regions. Finally the building integrated photo voltaic (BIPV) projects which are conducted in Malaysia have been evaluated..

 

CLICK HERE to order complete paper.

 

Readings:

IEEE Guide for Solar Power Plant Grounding for Personnel Protection

Risk Assessment of Rooftop-Mounted Solar PV Systems

Analysis of Lightning Surge Effects on Small-Scale Rooftop Photovoltaic Systems

Dehn-International White Paper: Lightning and surge protection for rooftop photovoltaic systems

Lightning Protection Systems

 

Lightning Protection Systems

Beef Teaching Farm

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