Satish Kamble, Managar-MEP Design at Hosmac answers questions on designing efficient MEP systems in hospitals.
Mechanical and electrical engineering are like the nerves of the hospital. When working on a green field hospital project, what is an ideal cost percentage that should be allocated to MEP?
Yes, Mechanical Electrical and Plumbing (MEP) engineering are the nerves of a hospital as after commissioning, MEP engineering is crucial in representing the performance and efficiency of the building.
Earlier, when awareness of green building was not prominent, the cost of green building construction was about 30-40 % higher as compared to traditional MEP engineering in the building. Nowadays due to awareness of green buildings and the changed perspective to reduce operating cost of the building, MEP engineering by default is designed considering basic green building measures. Hence considering that cost into mind, there is an increment in the spend by around 15-20 % with the fluctuation in cost being attributable to the green building energy rating (i.e. Platinum, Gold, Silver etc.)
What are the latest trends in designing energy efficient systems?
- Use of Energy efficient MEP equipments i.e. Chillers with high COP more than 6.5, High delta T chillers to reduce energy bills
- Use of highly Energy efficient IE-3 motors for MEP equipment’s
- Use of waste heat recovery system for air and water both through energy wheels/heat pipe
- Water recycling to obtain zero discharge of the water
- Use of energy efficient heat pump for central hot water system instead of local geysers
- Maintaining Power factor closed to Unity to minimize power losses
- Use of under deck insulation of exposed area to minimize heat gain into floor below
- Use of low flow fixtures in plumbing engineering etc.
What can a hospital do to improve Infection Control via MEP?
There are many measures we can follow for infection control as it is most crucial part in hospital industry; most of the infection is caused due to poor air quality which is called HAI (Hospital Acquired infection).
- It is essential to maintain desired ACPH (air changes per hour) as per the latest guidelines of ASHRAE- 170 which is specifically assigned for healthcare industry. Proper ACPH helps to replace fresh air with used air and thus helps to maintain required fresh O2 level inside the hospital
- It is must that positive pressure is maintained inside hospital premises so that outside air infiltration can be prevented through door opening and minor leakages
- Use of UVGI system (Ultraviolet Germicidal Irradiation) on cooling coil and supply duct so that infection can be killed at the source only before generation due to wet surface. Growth of microorganism at the wet surface is prevented with the help of high intensity UV lights destroying Genes of Bacteria and viruses
- Use of double filtration ( MERV-7 as pre-filter and MERV-14 as fine filter at all air handling units to filter air particles so as to improve IAQ ( Indoor Air quality)
- It is essential that proper percentage of fresh air and exhaust air be maintained so that to ensure aspect of –ve and +ve pressurization is maintained as per the application.(i.e. infectious isolation rooms required –ve pressurization for TB patients whereas protection room for BMT, hear transplant patient etc. requires +ve pressurization).Exhaust air also has to be discharged at the highest level of the building so as not to spread infection to the other adjacent area.
How can we build resilience into hospital buildings?
Hospitals are operation 24*7. It is very essential that 100 % power back up is maintained especially in rural areas where as frequent load shedding happens. This can be done in following general manner:
- DG Sets are provided in multiple quantity of the demand electrical load
- UPS system is provided to provide power back up during the lag period of power outage and DG start for crucial areas like, OT, certain medical equipment, emergency lights etc. UPS is normally provided for 15 minutes to 30 minutes back up.
- These days, thermal storage is also done to store AC energy in case of power failure to reduce huge load of chiller in case of emergency.
What does electronic surveying though BIM mean?
BIM is the advanced platform for electronic surveillance for feel of reality before the project is built at actual. You can prepare actual MEP model and see for clash detection of all MEP services and resolve at model level before actual installation. Aside; there are manpower/material scheduling, project cost, energy analysis etc. which can be obtained through this BIM platform. This keeps a client well informed about the project.
There are many fire norms which a building has to follow as per the category of the building, height of the building and the area of plot covered. NBC-2016 is for minimum fire-fighting guidelines whereas NFPA-13, NFPA-10,IS codes etc. are widely followed for sprinklers, fire extinguishers etc. Some of the norms which are normally overlooked are:
a) Provision of smoke extraction system for floors above basement
b) Use of 2 hours fire rated doors for Electrical room, AHU room, UPS room, IT room and server room
c) Use of FRLS cables for electrical system d) use of smoke detector instead of heat detector in parking area f) not using high temperature sprinklers into kitchen area etc.
What are the factors that are critical in designing electrical systems in hospitals?
Crucial factors in designing electrical system are:
a) Optimum Electrical load estimation is crucial to design optimum transformer capacity
b) Effective earthing system especially for medical equipment and OT
c) Lightening arrestors for entire building
d) Energy efficient lighting, power factor improvement
e) Electrical safety of all equipment
List 5 Priorities for MEP Maintenance in Hospitals
One must consider the following:
a) Preventive maintenance schedule of all MEP equipment
b) Periodical maintenance schedule
c) Energy metering and careful analysis of all major power consumer contributor MEP equipment such as Chiller, Pumps, heat pump, etc.
d) Training of all the maintenance staff and enhance their skill for advanced technology and to train them in know-how of the installed system
e) Preserve of essential spare parts of the MEP equipment in advance and getting a daily stock of store items to prevent shortage during emergency and breakdown of equipment
f) Tracking on AMC/CMC of the OEMs are crucial and personal attention/witness to their service is essential from our own staff for proper care of the installed MEP system