N2O exists in the atmosphere, measured at about 330 PPB in 2020 and is increasing yearly. It is a scavenger of stratospheric ozone and is considered to have a negative impact on the environment similar to CFC refrigerants.

Background

Historically, N2O has been used in healthcare facilities (“HCF”) for anesthetic and/or analgesic purposes:
(1) Anesthetic use has often been as the “carriergas” for delivery of vaporized anesthetic agents (Sevoflurane, Isoflurane and Desflurane as examples) to a patient using a breathing circuit and undergoing general anesthesia, (2) Analgesic use has traditionally been for pain management and can be clinician- or patient administered (for example, by expectant mothers breathing N2O to reduce pain associated with contractions). Typically, it does not require the use of a breathing circuit (anesthetic machine) as the patient will be conscious while directly expelling the N2O into the room instead of into a breathing circuit. While N2O continues to have clinical application, there has been a significant shift to reduce its use, particularly in surgical settings, in favour of more environmentally-friendly anesthesia techniques.

N2O Consumption and Leakage Concerns

As HCF’s continue to grapple with reducing emissions, N2O has again come under the spotlight. In the US, the healthcare sector is responsible for an estimated 8.5% of US greenhouse gas emissions(1). Further, medical gases contribute up to 40% of hospitals’ direct emissions(2), with N2O pipeline leakage alone contributing upwards of 90% of the N2O consumption when measured against actual clinical consumption use. It has been known for some time that most centrally piped N2O pipeline leakage occurs through the plastic hoses used in ceiling arms (aka booms, articulating arms, ceiling pendants) that can move vertically and horizontally, as well as the plastic hoses supplied with equipment that connect to a terminal unit (outlet). N2O is known to permeate these plastic hoses. The leakage of N2O through the plastic hose is typically across its entire length. Teflon pigtails used to connect nitrous oxide cylinders to a cylinder manifold have also been found to leak, but the CSA Z7396.1 standard banned the use of polymer-lined flexible metallic pigtails for pressure gases in favor of copper pigtails.

Health Effects of Exposure to N2O

Studies have reported adverse health effects for workers exposed to N2O. These include reduced fertility, spontaneous abortion, and neurological, renal and liver disease(1). Patient and clinical staff health effects can also include nausea and vomiting(1). There have been studies on acute and chronic exposure to individuals or groups inside a HCF(4). The results indicate a significant difference in health effects for groups exposed to N2O which include headaches, dizziness, nausea, vomiting, euphoria and tachycardia (heart rate > 100 bpm).

Recent Opinion from the Canadian
Anesthetists Society on N2O Usage

In 2024, the Canadian Anesthesiologists’ Society (CAS) issued their revised edition of Guidelines to the Practice of Anesthesia.(5) In this guideline, Section 10 (page 31 Guidelines for Environmental Sustainability), indicates the following points with regard to N2O:

“The use of desflurane and N2O should be eliminated or minimized to the extent possible given local resources, locations, and the clinical context.”

“Environmentally-friendlier anesthesia techniques such as neuraxial/regional anesthesia and total intravenous anesthesia may be considered as alternatives to volatile inhalational anesthesia to minimize greenhouse gas burden when clinically appropriate, feasible, and available.”

Recent Opinion from the Association des anesthésiologistes du Québec (AAQ)

On April 25, 2024, the AAQ(3) issued the following statement: AAQ aposition statement on N2O pipelines The Association des anesthésiologistes du Québec Board of Directors, representing the largest traditional users of medical N2O, has unanimously taken a position on N2O pipelines in hospitals on April 25:

“The AAQ supports decommissioning central N2O pipelines in existing hospitals, no longer installing them in new hospitals, and, if necessary, working with N2O cylinders.”

Furthermore, the elimination or minimization of N2O from anesthetic practice has been a recommendation of the Canadian Anesthesiologists’ Society’s Guidelines to the practice of anesthesia since 2023.

Recommendations

Given the opinions from the CAS and AAQ to pivot away from using N2O in favour of other friendlier anesthesia techniques, and coupled with the known leakage concerns from centrally piped N2O pipeline systems, an opportunity exists for HCF’s to reevaluate with their anesthesiology department stakeholders the clinical use of N2O and the delivery method. Reevaluating N2O usage and delivery methods also aligns with Annex P recommendations in CSA Z7396.1 medical gas standard.

Disclaimer

HH Angus cannot provide any opinion on the clinical use of N2O as this is a medical issue. This client advisory serves only to highlight recent opinions and studies on known problems associated with the leakage of N2O from centrally piped medical gas pipeline systems, as well as the recommendations from the CAS and AAQ. The HCF must make its own determination on the suitability of continued clinical use of N2O and the associated delivery methods.

Reference Sources

1. Decommissioning N20 Playbook - WORKING VERSION.docx (practicegreenhealth.org).
2. Collaborating to prevent nitrous oxide waste in medical gas systems_FINAL 5-2-2023.pdf (practicegreenhealth.org)
3. https://mcusercontent.com/195cedfbb43cfc829ac342437/files/d239380c-8484-d56a-92b4-c50f920bd63a/Prise_de_position_AAQ_N2O.03.pdf
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5661723/
5. https://www.cas.ca/CASAssets/Documents/Practice-Resources/Guidelines/CAS_Final_Guidelines_2024.pdf

For More Information

Edward Hood, P.Eng.
Principal | Engineering Director, Health
Edward.Hood@hhangus.com

Porter Airlines officially opened its new aircraft hangars and maintenance base at the Ottawa International Airport. The two hangars comprise approximately 150,000 ft2 and can house eight aircraft, along with offices, general records storage, parts storage, engine shop, avionics, paint shop, wheel shop, and employee facilities.

The two massive aircraft hangars are part of a series of projects to revitalize Ottawa Airport to accommodate increased air travel demand in the National Capital Region. The hangars represent an important partnership for the city to grow and provide more flight options. Porter’s expansion in Ottawa includes 16 new non-stop routes, with about two million passengers expected through the airport in 2024. By year’s end, Porter aims to employ more than 400 staff in Ottawa.

The project was designed by Scott Associates Architects, with construction management by PCL and Span Construction & Engineering. HH Angus provided mechanical and electrical consulting engineering, as well as ICAT consulting and security design.

Completed in two phases - the first in late 2023, and the second in 2024 Q1 - the hangar will serve as a primary maintenance base, with 200 local hires, including 160 aircraft maintenance engineers, shop technicians and administrative support staff.

Sustainability is increasingly important in aviation facilities. One of the project’s key design criteria was to exceed current energy efficiency standards, in line with the airport’s commitment to net-zero operations by 2040 or sooner. Some of the hangars’ important sustainability features include:

A predominantly electric fleet of vehicles for towing and servicing aircraft, as well as ground support
Constructed with approximately 35% recycled steel that can be recycled at the facility’s end of life
Constructed from materials with 28% lower embodied carbon than conventional tilt-up assemblies
City fire hydrant system is fully supplemented by an onsite underground water storage tank capturing approximately 1.2 million litres of excess rain/stormwater to avoid overstressing existing city mains.

HH Angus is currently working on Porter’s new airport terminal building in Saint-Hubert/Montréal, a net-zero facility with all building systems to fully operate on electric power. We also provided engineering services for the L.F. Wade International Airport in Bermuda, and were involved with the revitalization of the Billy Bishop Toronto City Airport completed in 2011, as well as its further expansion in 2014.

We are honoured to be named among Canada’s Best Managed Companies (CBMC) for 2024, our sixth consecutive year of being recognized. The CBMC award, Canada’s leading business award program, recognizes excellence in overall business performance, entrepreneurial spirit and the success of best in-class, Canadian-owned and managed companies with revenues exceeding $50 million.

“Best Managed is a prestigious award that recognizes the significant and ongoing contributions within Canada’s business landscape,” said Lorrie King, Partner, Deloitte Private, Global Best Managed Leader and Co-Leader, Canada’s Best Managed Companies program. “Companies such as HH Angus and Associates who attain this high standard of excellence demonstrate consistent adaptability, versatility, and strategic acuity. Year after year, they thrive in a competitive, rapidly changing market and should be proud of their growth.”

The leadership of HH Angus continues the firm’s commitment to the innovation, professional development and technical expertise that has enabled us to thrive for 105 years. For us, the CBMC award underscores the importance of carefully managing day-to-day operations, strategic planning for the future, and investing in growth opportunities.

Equally important is maintaining a strong company culture; our staff of over 400, across our offices in Vancouver, Toronto, Ottawa and Montreal, is successfully delivering a broad range of projects in Canada and internationally to help our clients achieve their goals. They also share our focus on decarbonizing the built environment to help protect the planet, as well as providing a wide range of services to support the development of smart and sustainable cities. We understand this honour would not be possible without the commitment and loyalty of our employees and the trust of our clients – we appreciate the important role you play in HH Angus’ success.

Here is the full text of today’s announcement of Canada’s Best Managed Companies.

HH Angus a été nommée l’une des sociétés les mieux gérées au Canada pour la sixième année consécutive

Nous sommes honorés d'être nommés parmi les sociétés les mieux gérées au Canada en 2024, notre sixième année consécutive de reconnaissance. Le programme des sociétés les mieux gérées au Canada, le plus important programme de récompenses pour les entreprises au Canada, reconnaît l'excellence des performances globales des entreprises, l'esprit entrepreneurial et la réussite des meilleures entreprises de leur catégorie détenues et gérées par des Canadiens et dont le chiffre d'affaires dépasse 50 millions de dollars.

« Le palmarès des Mieux gérées est une distinction prestigieuse qui souligne les contributions importantes et soutenues dans le milieu des affaires canadien », a déclaré Lorrie King, associée, Deloitte, leader mondiale du programme des sociétés les Mieux gérées au Canada et coleader du programme des sociétés les Mieux gérées au Canada. Les entreprises comme HH Angus et associés qui atteignent ce niveau élevé d’excellence font preuve d’une capacité d’adaptation, d’une polyvalence et d’une acuité stratégique constantes. D’année en année, elles prospèrent sur un marché concurrentiel qui évolue rapidement et elles devraient être fières de leur croissance. »

La direction de HH Angus est fière de maintenir l'engagement de l'entreprise en faveur de l'innovation, du perfectionnement professionnel et de l'expertise technique qui nous permettent de prospérer depuis 105 ans. Pour nous, le titre de sociétés les mieux gérées au Canada souligne l'importance d'une gestion minutieuse des activités quotidiennes, d'une planification stratégique pour l'avenir et d'un investissement dans les possibilités de croissance.

Le maintien d’une solide culture d'entreprise est tout aussi important; notre effectif de plus de 400 personnes, réparti entre nos bureaux de Vancouver, Toronto, Ottawa et Montréal, réalise avec succès un large éventail de projets au Canada et à l'étranger afin d'aider nos clients à atteindre leurs objectifs. Notre équipe partage également notre volonté de décarboner l'environnement bâti pour contribuer à la protection de la planète, de même que de fournir une large gamme de services pour soutenir le développement de villes intelligentes et durables. Nous sommes conscients que cet honneur ne serait pas possible sans l'engagement et la loyauté de nos employés et la confiance de nos clients. Nous apprécions le rôle important que vous jouez dans la réussite de HH Angus.

Voici le texte intégral de l’annonce faite aujourd’hui à propos des sociétés les mieux gérées au Canada.

Image of HHA team accepting award on stage

The Association of Consulting Engineering Companies recently honoured the Pearl Street Energy Centre project with an Ontario Engineering Project Award.

We are delighted that the Enwave’s Pearl Street Energy Centre (PSEC) project has been recognized for its technical innovation and positive contribution to reducing greenhouse gas emissions in the City of Toronto.

The objective of the PSEC project is to expand Toronto’s district heating and cooling distribution and capacity using low carbon technologies by installing 3600 tons of cooling and 62,000 Mbh (thousand BTU’s per hour) of heating, using water source heat pumps (heat reclaim chillers). Enwave’s ‘Green Heat’ offering will be made possible by the installation of new assets that make use of waste heat while producing cooling and hot water. HH Angus is serving as Prime Consultant and Mechanical and Electrical Design Engineers for the project.

Toronto’s buildings generate more than half the city's greenhouse gas emissions. New technologies, such as Enwave's expanded heat delivery system, will play a critical role in reducing the city’s cumulative carbon footprint. When fully utilized, Enwave’s low carbon heating facility will provide enough low-carbon heating to reduce emissions in Toronto by approximately 11,600 tCO2e, the equivalent of converting over 10 million square feet of office space to net zero. Providing Enwave clients with low to zero carbon heating and cooling solutions for their buildings will contribute to making them environmentally and socially responsible in Canada’s goal to reduce and potentially eliminate greenhouse gases.

To read more about this project, click here. https://hhangus.com/projects/enwave-energy-corporation/

The building code now mandates that any interconnections or data transfers between two or more building systems with life safety or fire protection functions must be tested in compliance with CAN/ULC-S1001 standards.

What is CAN/ULC-S1001

CAN/ULC-S1001 is a document that provides a methodology for conducting a documented testing program of interconnections between two or more fire protection and life safety systems. For clarity, this standard does not include testing of those individual systems themselves.

This ULC standard defines, among other things:

• the documentation of the test methodology (the test plan) and the results of the implementation of the test plan (the test record)
• the qualifications of the individual/company conducting the testing of these
• interconnections (the integrated testing coordinator or “ITC”)
• the responsibilities of the contractor, installation contractor and design professionals in this testing process

Who is the ITC

One thing the standard does not state is ‘who hires the ITC?’ Under this
standard, nearly anyone can be the ITC, including the owner, provided
they meet the requirements for specialized knowledge and experience.
Although not yet required by the various provincial building codes[1],
ULC offers a voluntary certification program for individuals and companies
for provision of ITC services which conform to the requirements of
CAN/ULC-S1001, an option that might be considered for any project.

Going Forward

On your next project, whether it is a new building, or modifications to an
existing building, the following two questions must be asked:

1. Are there new or modified interconnections between two or more fire protection and/or life safety systems? If yes (even if there is
only one interconnection), then integrated testing in accordance
with CAN/ULC-S1001 is required.

2. Who will retain the ITC? The ITC could be the Owner’s staff, or a
3rd party testing agency hired by the owner or by the general contractor/construction manager

3. Multi-Party Process - Under the standard, there are multiple parties involved in this testing process, including the “integrated testing coordinator”, designers (engineers and architects), the installation contractors, general contractors/construction managers, and owners - each with designated responsibilities for compliance with this standard. While this testing involves a number of mechanical and electrical systems, it also affects vertical transportation, security doors, automatic fire shutters, fire door release devices, construction safety, and methods of contracting, etc. The Ontario Association of Architects, OAA News 2023/Jan/23 recognizes this is a multi-disciplinary effort to achieve the goals of this test standard.

Do not delay getting the ITC onto your project – completion of the
integrated testing will be a pre-condition for obtaining occupancy of the
building, and will be required by the design professionals and building
departments.

Examples of interconnections between various building systems