Canada is usually associated with our long cold winter. To take advantage of the cold weather, we go out for skating, skiing, snowshoe hiking, ice fishing, snowmobiling, etc., tons of fun activities. Is there anything we can do at hospitals to make full use of the winter? Actually there is. Our hospitals have much essential medical equipment that requires cooling year around. Magnetic resonance imaging (MRI) is one example. It relies on deep cooling to maintain super-conductors inside to generate extremely strong magnetic field and radio waves to do very detailed scanning of patients. The temperature required is so low for super-conductors that they are submerged in liquid helium, which is about -270 °C (-454 °F).
Figure 1: Typical MRI Scanner Cutaway
A typical MRI scanner uses Continue reading
We had a secret steam room at Toronto Western Hospital. If you knew where it was you could drop by and enjoy it, free of charge. This place was hidden somewhere in the underground tunnel. The heat was free from our high pressure steam and condensate pipes between the boiler plant and the hospital. The temperature in this area was over 40°C (104°F) year around. Most of the pipes were insulated, however, there were still many exposed hot surfaces, such as pipe hangers, anchors, supports, valves, condensate pumps, etc. Due to the temperature difference between the high pressure steam (170°C or 338°F) and space, the heat loss was nonstop.
Figure 1: A secret steam room hidden at TWH. Continue reading
At the centre of Princess Margaret Cancer Centre (PM) is 2-level atrium separated by a huge and beautiful skylight on 7th floor. Every year, there are numerous events such as Music in the Atrium, fund raising, seminars, etc. on 7th floor around this skylight area. Continue reading
Clean water is essential for modern buildings and hospitals are no exception. Toronto and many cities usually supplies tap water at around 50 psig, which is only good for low rise buildings. At PMH the building on 610 University Ave. side is 20 story high (we got 2 levels on 19th floor and there is 13th floor which is not accessible by elevators) so there is no way city water can go that high. Thanks to some genius Continue reading
If you work at Toronto Western Hospital or if you have visited the site, you may know that we have an underground 2-level parking garage below Fell Pavilion. To provide enough lighting for drivers, 21 powerful 250W high pressure sodium (HPS) lighting fixtures were installed on parking garage entrance ramp sidewall, some are outside and some are inside. Those lighting fixtures share a few circuits together so the only way to run the outside ones is to keep all the lights on 24/7. As an energy project manager I felt guilty every time I passed by the ramp area.
HPS was invented by GE in 1960s. The bulb contains a small amount of solid sodium inside a glass tube. When heated up the sodium would vaporize and the lamp would glow yellow. Typical construction is shown as below:
HPS has higher efficiency when compared with Continue reading
Have you ever imagined hospital shutdown in the middle of summer? It is possible if Continue reading
Last time we talked about chilled water system upgrade at TWH. The chilled water is pumped to various mechanical rooms to cool air supplied to the hospital, medical equipment such as MRIs and some local refrigeration machines. Then it comes back to the central chiller plant and is cooled down by the chillers. The chillers use refrigerant to transfer the heat from the building to condenser water side. You may be curious where the huge amount of heat removed from the hospital goes. The answer is Continue reading