Category Archives: Writings

Egress, toilets, and carcinogens: Cornell’s transition plans during Fine Arts Library construction


[Updated below: May 2, 2017, May 10, 2017, and May 22, 2017] Cornell has made transition plans for the construction of a Fine Arts Library (FAL) in Rand Hall in order to accommodate the various library, wood shop, metal shop, and digital fabrication functions, currently in Rand Hall, that will be out of service during the two-year construction period. Not mentioned in these transition plans are two items that actually affect Milstein Hall: the 2nd-floor Rand Hall toilet rooms that are used by faculty and students in Milstein Hall (since no toilets were provided on the 2nd-floor Milstein Hall studio level) and a third required exit stair for Milstein Hall’s 2nd-floor level, currently in Rand Hall. I’ve asked the AAP Dean and the FAL project manager what plans are in place for temporary toilets and egress, but have not yet gotten a reply. In the meantime, I’ve published a Cornell Chronicle parody on that subject.

Parody image showing temporary toilets in Milstein Hall during the construction of the rand Hall Fine Arts Library

There are other transition issues as well. A temporary digital fabrication lab is being constructed across from my office in E. Sibley Hall. It will house, among other things, 3-D printers, at least one of which uses toxic and carcinogenic materials. The room itself appears to have no ventilation system that supplies fresh air, in apparent violation of the 2015 NY State Mechanical Code. I’ve written a series of emails to Cornell’s mechanical systems designer as well as the director of facilities for the College to try to get some answers to my questions and concerns. After three weeks of waiting and promises of a reply (“The project team, including Facilities Engineering and Environmental Health & Safety, is reviewing the information you have provided and will respond to your concerns once the review has been completed.”), I still haven’t heard anything. Here is the last email I wrote to Cornell’s mechanical designer, dated April 19, 2017:

I haven’t received a reply to my last email, dated April 10, 2017, so I’ll repeat my main questions and concerns. Since the questions are technical in nature, and since you are the responsible mechanical engineer for this project, I would appreciate a response directly from you.

The safety data sheet for the “Stratasys” printer says that it should be used “only outdoors or in a well-ventilated area,” and the 2015 NYS Mechanical Code seems to require that “Ventilation systems shall be designed to have the capacity to supply the minimum outdoor airflow rate.” Your plans for 240 E. Sibley don’t seem to have any mechanical ventilation system for outdoor air—only transfer grilles that pull in return air from the adjacent spaces.

(1) Where is the required outdoor air coming from for this room?

(2) How is your design consistent with the manufacturer’s recommendation that the printer be used “only outdoors or in a well-ventilated area”?

(3) How can you be sure that particulate matter containing toxic or carcinogenic byproducts from the printer will not be exhausted directly in front of the rear entrance to Sibley Hall and a short distance from the food truck?

The context for my concern is that the material used by the printer is both toxic and carcinogenic, and nanoparticles are created as a byproduct of the printing process, some of which are so small that they pass through HEPA filters.

The manufacturer’s safety sheet says:

This chemical is considered hazardous by the 2012 OSHA Hazard Communication Standard (29 CFR 1910.1200)

Suspected of causing cancer
Suspected of damaging fertility of the unborn child
May cause respiratory inflammation
May cause damage to organs through prolonged or repeated exposure

Carcinogenicity: Classification based on data available for ingredients. Contains a known or suspected carcinogen.

Reproductive toxicity: Classification based on data available for ingredients. Contains a known or suspected reproductive toxin

SARA 311/312 Hazard Categories
Acute health hazard: YES
Chronic Health Hazard: YES

From Nanoparticles (ultrafine particles less than 1/10,000 of a millimeter) are one of the by-products emitted during the 3D printing process. Recent studies have shown that 3D printing using a low-temperature polylactic acid (PLA) feedstock can release 20 billion particles per minute, while a higher temperature acrylonitrile butadiene styrene (ABS) feedstock can release 200 billion.
Nanoparticles are of concern for the following reasons:
• They are very small,
• They have large surface areas, and
• Can interact with the body’s systems, including the skin, lungs, nerves and the brain.

Exposures to nanoparticles at high concentrations have been associated with adverse health effects, including total and cardio-respiratory mortality, strokes and asthma symptoms. While PLA feedstock is designed to be biocompatible, the thermal decomposition products of ABS feedstock have been shown to have toxic effects on lab rodents.

Thank you for your attention to this matter.

Links to all my writings and blog posts on the Fine Arts Library can be found here.

[UPDATE: May 2, 2017] I still haven’t heard back from “the Project Team”; meanwhile construction is underway, and one can easily see how any fresh air originating in the existing duct outside the room that manages to find its way through the grilles (at the top of the storefront partition) will be sucked directly into the existing return grille, also at the top of its wall, without providing much benefit to the occupants within the so-called “breathing zone” (Figure 1 below). In fact, it’s possible that particulate matter from the 3-D printers will find itself in a zone with no air movement at all, given the geometry of the room and the placement of grilles only at the top of the walls.

Figure 1. It’s easy to see that the placement of supply air (outside the room) along with louvers (grilles) at the top of the storefront partition and a return grille also at the top of its wall will discourage proper air circulation within the digital fabrication lab, currently under construction (photo by J. Ochshorn, May 2, 2017)

[UPDATE: May 10, 2017] I just received an email response from the AAP Dean indicating how Cornell intends to deal with Milstein Hall toilets (still trying to figure it out) and egress (temporary stair through the glass curtain wall) during the construction of a Fine Arts Library in Rand Hall:

Thank you for your question regarding the transition. Regarding egress, my understanding is that an egress stair will be provided directly from the Kwee studios by removing a glass panel and providing a temporary egress stair. I am told this will be part of the CD drawings.

Regarding the bathrooms, the project team is working with the city to determine the number of accessible and non-accessible fixtures not including Rand Hall. A solution is not yet final, but the team is aware of the issue.

[UPDATE: May 22, 2017] On May 19, 2017, I received a copy of a “health review,” concerning the Sibley Hall Digital Fabrication Lab, jointly written by Cornell’s Director of Occupational Health, Safety, Fire and Emergency Services and Cornell’s Director of Facilities Engineering. I emailed the following reply today to the AAP Director of Facilities (copied to other relevant parties):

Thanks for stopping by today and confirming that each 3D printer will now be placed in a separate “box” that filters air for nanoparticles and VOCs before returning the air to the room. This seems better than the original design in which the 3D printers were placed in the temporary digital fabrication lab (240 E. Sibley) without any specialized exhaust system. Still, even if 99.97% of nanoparticles are captured in this way, the 0.03% that escape constitute a potential release of 20,000,000,000 x 0.0003 = 6,000,000 toxic and carcinogenic particles into the breathing zone per minute. (“Recent studies have shown that 3D printing using a low-temperature polylactic acid (PLA) feedstock can release 20 billion particles per minute” –

Question 2 and its answer… confirm that the digital fabrication lab is not directly provided with outside air, but instead: “The Makeup Air Unit in Room 200UA delivers fresh air to the second floor. This air is then transferred into Room 240 through grilles located at the top of the glass partition wall.” Based on a conversation I had with Senior Technical Staff of the International Code Commission (ICC), transferring outside air from a corridor into the digital fabrication lab would not be compliant with the 2015 Mechanical Code. However, since the corridor seems to be now labeled as a room (“collaborative area”), it’s probably legal, but barely. The opportunistic and ad hoc manner in which such design decisions are, and have been made, does not inspire confidence.

Relatively little is known about the risks of exposure to 3D printers. A recent study says: “It is well-known that both gases and particles are emitted during thermal processing of many thermoplastic materials. However, little is known about the  types and magnitudes of emissions from desktop FFF 3D printers and how they vary according to filament material or printer characteristics. In 2013, we published the first known measurements of emissions of ultrafine particles (UFPs: particles less than 100 nm in diameter) resulting from the operation of a single make and model of commercially available desktop FFF 3D printer using both ABS and PLA filaments. These findings were crucial, as exposure to emissions from thermal decomposition of thermoplastics has been shown to have toxic effects in animals, and exposure to UFPs from other sources has been linked to a variety of adverse human health effects.” (Parham Azimi, et al., “Emissions of Ultrafine particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments,” Environmental Science & Technology, at, emphasis added).

It saddens me that students, faculty, and administrators in AAP feel the need to introduce toxic and carcinogenic materials into the educational environment. The competition to keep pace with our peers, and to prepare our students for professional practice in architecture, has apparently reached the point where even Monty Python’s prescient “Architect’s Sketch,” featuring “rotating knives” in a corridor where “blood pours down these chutes,” seems like a quaint anachronism.

On another note, I was told by the AAP Director of Facilities that no new toilet rooms will be provided for architecture students during the time when code-mandated toilet rooms in Rand Hall become inaccessible due to construction of the Fine Arts Library. Instead, a code variance will be sought.

Revisiting Form and Forces


I just presented a paper at the 2017 National Architectural Engineering Institute (AEI) Conference in Oklahoma City. The paper critiques graphical statics as a contemporary pedagogical tool. You can read it here.

While in Oklahoma City, I also went to see the final game played by the Oklahoma City Thunder basketball team, where Russell Westbrook was honored in a pregame ceremony by Oscar Robertson. Not everyone is up to speed on NBA trivia; to learn more, read this NY Times article.

Cornell’s proposed Fine Arts Library at 100% design development


Cornell’s 100% design development (DD) drawings for the proposed Fine Art’s Library have been completed. The scheme continues to have serious fire-safety deficiencies, continues to be non-compliant with the New York State Building Code, and continues to be problematic for non-Code reasons as well: it destroys a flexible “low-value” industrial-type building that was extremely useful for the department of architecture and replaces it with a spectacularly useless mausoleum for the display of books. You can read more of my articles and blog posts about this project here.

Today, one day before the anniversary of the Triangle Shirtwaist Factory fire, I offer two more reading options: first, a detailed analysis of the latest 100% DD drawings (and Cornell’s Code variances) and second, a Cornell Chronicle parody covering the same material.

This photo accompanies my Cornell Chronicle parody.

A Fulbright journal: Five months in Tianjin


I kept an electronic photo-journal for five months while living in Tianjin, China, as a U.S. Fulbright Scholar. During my time there during the fall 2016 semester, I taught two courses in the School of Architecture at Tianjin University, and also lectured in several other cities in China. You can read my journal in one of two formats: either as a black and white paperback book (click here to order a copy), or as a full-color pdf, embedded below. It takes a short time for the pdf viewer to load; click on the “fullscreen” button in the middle of the horizontal menu bar to enlarge the content.

[March 26, 2017 update] I’ve uploaded some random videos: Scenes from China.

Steel truss design


I’ve written a paper (not yet online) about graphical statics. In order to demonstrate that the “form-finding” objectives of such techniques are often superficial and flawed, I needed to provide a case study of an actual structural design problem, using real materials and real design methods, that accounts for things (like the buckling of bars in compression, or shear lag and effective net area of bars in tension, or deflection issues) that graphical statics ignores. So I created an enormous spreadsheet to find the optimal (lightest) steel double-angle Pratt or Warren truss for any given span, spacing, and loading condition. The spreadsheet actually designs 105 different trusses (with aspect ratios ranging from 2:1 to 16:1; and with from 2 to 14 “panels,” as shown in Figure 1) in order to find the optimal combination of aspect ratio and panel geometry for a given span, spacing, and loads.

Figure 1. Trusses are designed with from 2 to 14 panels

Figure 1. Trusses are designed with from 2 to 14 panels

Well, the spreadsheet had well over 1,000,000 cells and couldn’t be converted to an online calculator using the software I have. Therefore, I made a smaller version of the same spreadsheet — this one only designs a single truss (rather than 105 versions) and only considers whatever aspect ratio and panel geometry have been selected. However, this calculator can also be used to find the lightest truss, but only by trying out numerous geometries while keeping track of the truss weight.

Second edition of Structural Elements published


The second edition of my structures text, Structural Elements for Architects and Builders, has just been published by Common Ground Publishing. More information can be found here.

Second edition of Structural Elements for Architects and Builders

Second edition of Structural Elements for Architects and Builders

The new edition is substantially different from the first edition, which was published by Elsevier, with reorganized chapters and much new material, including new sections on material properties and systems for wood, steel, and reinforced concrete.

The new publishers have a different business model from Elsevier, and are able to offer much lower prices: only $30 for the paperback version and $10 for an electronic (pdf) version.

Thanks to Susan Schwartz for the cover photo of Schwartz Auditorium in Rockefeller Hall at Cornell.

Summary and critique of latest LEED reference guide (v4)


I’ve just completed a summary and critique of the latest LEED reference guide (v4) for newly constructed “green” buildings. This is the third such critique that I’ve posted online: my first such attempt was back in 2007 for LEED version 2.2, and my second summary was posted in 2010 for LEED’s 2009 edition. I’ve also posted a table with links to the various LEED sections (“categories’) within the three critiques.

Here’s a sample of my critique from the v4 Introductory section:

U.S. buildings actually produce relatively little CO2, mainly by burning oil or gas for heating and hot water. The big generators of global warming gases are not buildings, but rather the coal-burning electric utilities. By including the CO2 emissions from electric power plants in the category of “buildings,” LEED essentially lets the electric utilities off the hook — their contribution to global warming is barely mentioned in the reference guide. The reason for this is clear: LEED has no interest in threatening the infrastructural basis of corporate profitability by challenging the cheap supply of energy. In fact, LEED is not interested in any form of regional, national, or global planning that might actually address the questions it raises. Rather, it’s ideology is consistent with that of the corporate entities it serves so well, providing as it does a branding tool to validate their “sustainable” and “green” efforts: according to LEED, one must tap into the corporate desire for profitability, and put into motion the miracle of “markets” to solve all problems, one building at a time. In spite of LEED’s claim that the nonresidential (i.e., corporate) “green building portion of the construction market” has achieved a 35% market share in 2010, the planet continues to lurch closer and closer to some sort of disastrous climate crisis, global poverty persists, and most workers still “lead lives of quiet desperation.” But as long as the LEED brand grows, these counter-indications won’t dampen the spirits of the pragmatists in the USGBC (the U.S. Green Building Council is the not-for-profit organization that created the LEED rating system) or call into question their vision of a voluntary, consensus-based, market-driven program.



When living in Hong Kong in 1997-1998, I discovered that Chinese fortune cookies do not exist in China, but rather are an American innovation. In my early days eating American Chinese food, I got used to the idea that the fortune cookies supplied with the check at the end of the meal actually did contain a fortune — that is, a prediction of what would happen to you sometime in the future.


These fortunes always had a positive, or optimistic, character, since it would clearly be counter-productive for a restaurant to deliberately give its customers bad news.

At some point, however, the fortunes in fortune cookies seemed to change their character; in fact, they were no longer fortunes at all, but merely trite pronouncements about life.


Not having an actual fortune in a fortune cookie was discouraging to me, since there are already enough trite pronouncements about life available through mass media and news programming; it seemed hardly necessary to work my way through the plastic packaging of the cookie, and crack open the hard shell of cookie material, in order to get yet another annoying message about love, life, and work.

Yet I continued to pry open these strange clams of brittle dough, perhaps hoping that an actual fortune would emerge — something I could ridicule freely and with pleasure. Imagine my surprise, then, when I recently opened a fortune cookie at Ling Ling Garden restaurant in Ithaca, NY, and received neither an optimistic message about my future nor a facile observation about life, but a shocking rebuke and warning: “Your problem just got bigger. Think, what have you done.”

from Ling Ling Garden, Ithaca, NY

I was literally stunned. Was there a rogue employee somewhere in the fortune cookie production line planting dystopic messages in these cookies? And if so, why? And was this message/warning unique, or were there others like it? My mind raced feverishly thinking of the possibilities: “The man behind you has a gun. Your life is in danger.” “Hundreds of large rats have entered your home. Extermination is impossible.” “Your computer just crashed, and none of your important work was backed up. You will lose your job.”

In the end, we paid the bill and left the restaurant. I haven’t dared return.

fashionable building


I recently found the type-written original copy of my first “scholarly” paper, written in 1983 and rejected for publication in the Journal of Architectural Education. I still think it explains quite a bit about architectural fashion, competition, and the peculiar type of architectural pedagogy that results. I’ve put the whole thing online here.