It is with profound sadness that we announce the passing of our great friend and colleague, Peter Willings, Chief Engineer (Emeritus) of HH Angus and Associates.

Peter joined HH Angus in 1963 as a young engineer out of Australia.  With obvious skill and tremendous engineering knowledge and instincts, he rose steadily through the ranks to become the company’s Chief Engineer in 1987, responsible for all facets of the firm’s engineering practice, directing and advising staff engaged in the design and preparation of drawings and specifications of Mechanical and Electrical Systems, and the supervision of installations for institutional, commercial and industrial undertakings.

One of Peter’s milestone projects at HH Angus was working with Architect Rod Robbie on Toronto’s SkyDome (now the Rogers Centre).  He had previously worked with Robbie on the Canadian Pavilion at Expo 67 in Montreal. Other career highlights include winning a National Low Energy Building Design Award; the iconic Toronto Dominion Centre (shown at left); the Queen’s Park office complex; the Eaton Centre’s Dundas Tower; and a long list of hospitals, computer centres and post-secondary projects too numerous to mention.

Peter’s dedication – to engineering in general and to HH Angus and Associates in particular- is a remarkable and increasingly rare achievement. He served the firm with distinction for -  54 years, continuing to work and to make significant contributions long after his official retirement. We have been the fortunate colleagues who benefited from Peter’s insight, his innate understanding of engineering, and his vast generosity in sharing that knowledge.

He will be deeply missed.

Hospital redevelopment projects provide a unique opportunity to build for the future

The increasingly critical role of technology in patient care has resulted in a dramatic increase in demands on communications and information technology infrastructure in hospitals, but aging facilities pose significant challenges to the staff who support and maintain these systems. Many hospitals in Canada were constructed well before the emergence of modern information technology, which typically means telecommunications equipment is squeezed into undersized spaces without sufficient power or cooling to ensure these important systems stay operational.

IT spaces added as an afterthought to existing construction In older buildings, telecommunications spaces have gradually expanded as the systems grow, creating a
number of challenges:

  • Locations are often chosen based on what space is available, rather than what is appropriate, meaning that the size and shape of the rooms may not properly support the equipment, or the site may be adjacent to
    wet piping or sources of interference.
  • Addition and removal of equipment over many years often results in an inefficient layout and lack of appropriate cable management or identification, making maintenance more difficult.
  • Supporting services, including power and cooling, may not have the appropriate capacity or redundancy for IT loads, and equipment shutdown for maintenance and repairs can impact the availability of these services.
  • Limited ceiling space in older facilities can impact the ability to add services (i.e. chilled water loop) or new communications cables.

Limitations have a significant budget impact
All of these challenges can have a significant impact on operational and capital costs, and can add up to multiples of what is typical of a new installation with properly designed spaces and systems.

The greatest impact is seen in operational costs, where limitations make the systems more difficult to maintain, support and upgrade. From a user perspective, network performance can be affected by things such as heat or interference, which can create unnecessary delays in accessing information or even unplanned network downtime – a condition which critically impacts patient care across the entire facility. However, capital costs are not immune to these conditions either; overheating, dust and vibration can reduce the lifespan of equipment, meaning it must be replaced sooner.

Redevelopment with the future in mind
Hospital redevelopment provides the opportunity to build new IT systems that can withstand the test of time, and to address issues with existing systems in order to support expansion. While no one can predict the needs of technology decades from now, the following principles will help avoid creating similar challenges in the future:

  • Engage users early on in the planning process, and design IT systems to align with the technology vision for the hospital. This approach facilitates adoption later on and helps ensure IT systems can support the
    unique needs of the facility.
  • Consider the facility as a whole when implementing new IT systems and infrastructure; design decisions for new spaces can have a significant impact on existing IT infrastructure, and a gap analysis can help prevent unpleasant surprises later on.
  • Provide additional capacity and flexibility in infrastructure, spaces and supporting systems so they can be adapted as technology progresses.
  • Aim for consistency in services throughout the facility. Differences in system performance or user experience can impact adoption, staff satisfaction and, in the case of clinical life safety systems, even patient safety.

It is also worth investigating which challenges can be addressed in place and which would benefit from a “greenfield” solution. For example, building a new data centre in a newly constructed area of the building is often less complex and cheaper than mitigating issues with the existing location. Many redevelopment projects use this opportunity to create a space that is properly sized and designed to support critical IT systems for the entire facility. The practicality of options should be evaluated as part of the planning process.

Ultimately, redevelopment projects are a chance for hospitals to create efficient and cost-effective IT systems capable of supporting the critical nature of technology in healthcare, and support the highest standard of patient care.


Kim Osborne Rodriguez,P.Eng., RCDD
Published June 2016 in the Canadian Healthcare Engineering Society website

Montreal mega-hospital project, CHUM (Centre Hospitalier de l’Université de Montréal) is featured as the cover story in this month’s issue of Canadian Consulting Engineer magazine. The story profiles the mechanical and electrical engineering for the project, as described by HH Angus Vice President and CHUM project lead, Nick Stark, P.Eng., LEED® AP, ICD.D. Also featured is the structural engineering by Pasquin St-Jean et associés.

Nick Stark’s article describes the complexity of engineering this enormous project (2.5 city blocks, 334,000m2), which is being delivered, financed and maintained by Collectif Santé Montréal.  The project replaces three hospitals in Montreal and includes a 20 storey acute care block, 772 beds, 39 operating rooms, and a full cancer centre.  CHUM is one of the largest P3 projects in North America. Phase 1 is scheduled to open by the end of 2016.

Click here for the abridged pdf.

Click here to read the full magazine.

The first phase of the Centre Hospitalier de l'Université de Montréal (CHUM)  is almost complete. The structural and mechanical-electrical engineers describe the challenges of designing for this massive P3 construction project on a tight urban site.


By Nick Stark, P.Eng., Vice President
HH Angus & Associates
The mechanical engineering design for CHUM had to meet many challenges, not the least of which was the sheer magnitude of the project on a congested urban site. There was also a strict energy target, along with request-for-proposal (RFP) requirements that drove alternative approaches.

In spite of the challenges presented by its sheer size, the project design was completed in Revit, enabling enhanced coordination of more than 2,500 building services drawings. Over 60 MEP models had to be maintained and data driven processes were developed to manage the information. Online collaboration sessions were essential for coordinating the work between HH Angus in Toronto, the project office in Montreal, and Cannon Design offices across the U.S.

Locating the plant. Locating the heating, cooling and emergency generator plants for an urban hospital complex presents a challenge. Traditionally a plant of this size would be located at grade in a separate building where it could be isolated from the clinical functions of the hospital. However such space did not exist on the CHUM site. The initial schemes positioned the plant below grade, but the real estate proved too valuable and was needed for clinical functions.

HH Angus developed a scheme to locate the plant 80 metres in the air above the ambulatory block. The boilers and chiller share one level, and the generators and cooling towers share another. These floors sit on top of an air handling plant room, forming a volume 30 metres high, fully enclosed with louvres. With this location, the design had to overcome challenges for the mitigation of noise and vibration.

The central plant consists of six dual fuel hot water heating boilers with a total output capacity of 30,900 kW, six dual fuel steam boilers and one electric boiler totalling 47,000 kg/hr. In addition to serving the needs of CHUM, the heating plant also supplies CRCHUM, the adjacent research centre, with steam and hot water. The cooling capacity is 9,000 tons in two multistage process chillers, two centrifugal heat recovery chillers and five conventional chillers.

  • Energy saving systems. The client mandated an energy consumption target of 40% less than the ASHRAE 90.1-1999 baseline — a very aggressive target for an urban acute care hospital. Every system that consumes energy was strategically assessed against possible alternative solutions.
    The modelling target was achieved using a multi-pronged approach that incorporated:
  • space by space control of air volumes (supply and exhaust)
  • enthalpy heat recovery wheels on virtually all air handling systems
  • reduced fan energy by reducing air velocity through air handling units and ductwork
  • process cooling and chiller heat recovery systems as the primary source of low temperature reheat water
  • a condensing boiler stack economiser
  • lighting power reductions coupled with occupancy and daylighting controls
  • control strategies including supply air temperature reset.
  • In terms of environmental and energy design, the building is targeted for LEED Silver designation, with a potential for LEED Gold.

Ventilation systems and heat recovery. Ventilation in a hospital is the system that requires the most plant space, not only in terms of plant room floor area, but also for vertical shafts and ceiling space. The RFP imposed a number of requirements, including HEPA filters on all systems serving clinical areas, no air recirculation between departments, and a high level of redundancy – all with a limited air handling unit size. To meet these requirements would have required two full intermediate mechanical floors and at the same time would have severely compromised the system’s future flexibility. HH Angus worked with CHUM to develop an alternative approach.

Where the RFP required a distinct air handling unit for each department, we proposed the use of 100% outdoor air units serving multiple floors where the occupancy was similar, and demonstrated to the hospital the merits of this approach from the perspective of infection control and future flexibility.

To mitigate the energy penalty of 100% fresh air systems, we proposed enthalpy heat recovery wheels. The RFP initially prohibited these wheels, but we used our 25+ years of successful experience with the technology to demonstrate to CHUM and their compliance team that their infection control concerns could be successfully mitigated with the right components and controls. The RFP was then modified accordingly.
The RFP also mandated a standby air handling unit for each unit serving a critical care space. This solution would have required much higher capital and operating costs over the life of the building, as well as more space. We developed an alternative approach by combining a number of air handling units together into one duct system to share the redundant capacity. This solution considerably increased the overall reliability of the systems while reducing operating costs.

Lastly we demonstrated that the restriction on air handling unit size could be raised to 33,000 l/s without any practical impact. Even so, 46 air handling units are required for a total supply volume of 1,300,000 l/s.

Combining these alternative approaches in the ventilation system design resulted in many benefits, including the ability to modify the occupancy of the spaces and enable future renovations. The net result was that additional clinical floors could be constructed under the zoning height restriction, which was a key factor in developing a successful bid.

Operating suites. The 39 operating rooms (ORs) had to be spread over two floors, even with a floor plate the size of two football fields. HH Angus located a main air handling plant room on the floor immediately above to enable direct servicing of the ORs. The supply and return terminal boxes as well as the terminal humidifier for each OR is located in the plant room, reducing the need for maintenance personnel to enter the ceiling space of the sterile area.

Plumbing and medical gas. The domestic water supply in a typical hospital may consist of one or possibly two pressure zones. For CHUM, with a difference in height of 120 metres from the lowest mechanical room five floors below grade to the roof, five separate pressure zones had to be created. The scale of the medical gas system is unprecedented: over 11,000 outlets.

Electrical distribution. The project required understanding the crucial demands placed on a hospital’s electrical system and knowledge of the intent and intricacies of codes and standards. Our team designed an electrical system that is robust, reliable and resilient, and one that met the owner’s RFP requirements in a cost-effective manner.
The high voltage distribution system includes 25kV and 4160V switchgear, with four incoming Hydro Québec lines totalling 36MVA. The emergency power generation system for the CHUM complex consists of four 2.5 MW diesel generators, generating at 600V, with four 2.5 MW back-up generators producing 4160V.

Lighting, fire protection and security systems. Lighting layouts were designed to balance the aggressive LEED requirements with CHUM’s stringent requirements for light levels. To provide an atmosphere that is elder-friendly efforts were taken to ensure even illumination, with gradual changes between adjacent spaces. The lighting is controlled by a building-wide lighting control system.

The addressable two-stage fire alarm system is combined with the public address system. Two complete CACF (central alarm and control facility) rooms were provided.
The security systems include CCTV, card access, intercom, and a real-time locating system. The card access system and CCTV system are IP based using POE (power over ethernet), which minimizes the risk of down time by using a centralized UPS system.

Published in Candian consulting engineer magazine - December 2015 edition (page 10)

Click to read complete article