In our current project, We have no option left to take make-up air for the dishwasher area except from basement carpark but due to the toxic chemicals (carbon monoxide) contained in vehicle exhaust system, we cannot directly take make-up air. I would like to know if there is any possibility to...
In my current kitchen ventilation design, I did not propose any sound attenuators on the ecology units' exhaust ductwork because grease is present in the exhaust air, this grease can build up in the sound attenuators and cause a fire hazard. In this situation, a different noise mitigation...
A metallic spiral slide (see attachment) is being constructed in the water park where children can play in the slide which is located in the water feature pond. This park is located in Dubai where ambient conditions are extremely hot and humid in the summer. To prevent hot metallic surfaces to...
I am calculating the stormwater holding tank capacity for a large park. I need help in considering the run-off coefficient in this case. The stormwater after percolating the soft scape/soil will enter into a perforated piping network which is provided below the soil layer. Eventually, all this...
I am currently doing calculations for the expansion tank of high rise tower. The chiller plant and associated expansion tank is located on ground floor. The expansion tank is located to the suction side of secondary chilled water pumps at ground floor. The highest level of piping in the system...
I am currently working on hotel tower and our client is insisting to provide insulation on drainage piping to avoid possible condensation due to condensate drain. As per project specifications, the condensate drain pipe to be connected to the nearest floor drain. It is to be noted that...
In car park ventilation system, there are 2 main supply fans connected in parallel through duct work. Both fans are duty fans as per our authority requirements. If any fan fails, there may be possibility back flow of air from another fan. if NRDs are not provided, whole car park ventilation...
As per attached ASHRAE reference, the recommended lowest chilled water pipe velocity to be maintained in chilled water pipes is 0.6 m/s. In my current fit-out project, I have to use existing chilled water pipes for new fit-out flow rates where the pipe velocities are dropping below 0.6 m/s. I am...
We have designed carpark ventilation system with 6 ACH at normal mode and 12 ACH at fire mode which is in line with NFPA and local regulations. However, following is also mentioned in NFPA 5000.
As per life safety code, NFPA 5000, (Ch. 49 CL.49.2.2.5) which specifies - Enclosed parking...
In primary / secondary chilled water system, we have 2 duty chillers and one standby chiller with corresponding primary and secondary pumps. Now, we want to provide air conditioning to the future expansion building without considering redundancy in the chillers and pumps. The pipe sizes are...
Our Atrium is one domain with extraction points in the ceiling located at 3 different spaces in atrium. The total smoke extract rate is 71 cum/sec. It was assumed that equal amount of extract air will be extracted from 3 different spaces (24 cum/sec) though there is no physical barrier between...
Currently, I am assessing the old primary secondary chilled water system. The system has 2 duty and 1 standby chillers with constant primary and variable secondary pumping system with a decouple pipe. the secondary pumping system is serving chilled water to total 10 low rise and high rise towers...
Hello Everybody,
In our recent project, we have proposed acoustic flexible duct sizes in a tabular form. The first size is 100 mm for 40 l/s which will provide friction rate of 4.35 p/m (0.56 In.Wg) and 5 m/s (1024 fpm) velocity. The proposed flexible ducts are pre-fabricated type with acoustic...
During commissioning, we have found that pump suction pressure at 150% of test is -5.0 PSI which is more than acceptable limit as per NFPA. We have also confirmed that static lift is positive as the water level in the firefighting tank is 800 mm higher than pump suction inlet. Moreover, the...
Hi,
I am currently writing a scope of chilled water commissioning for a large project. The primary chilled water is being supplied to the tower through remote area due to district cooling network. The tower is provided with secondary chilled water circuit and heat exchangers. There is a heat...
Can anybody guide me on the induction type VAV box and pressure independent type VAV box characteristics related to the uniform air distribution. Our client commented that, when we use pressure independent type of VAV box, the nearest diffusers from VAV box will supply more air then furthest...
One of our client is doing a high level of value engineering and expecing significant savings by changing the piping material from back steel to HDPE. Instead of connecting landing valve directly from the alarm check valve riser, the standpipe will connect to the external fire ring main made of...
In my current project, I have to prevent transfer of contaminants from antibiotic lab to the production area. The antibiotic lab and storage / production area is seperated by a link bridge. Though antibiotic area is kept at negative pressure with respect to the link bridge but it is still...
Is there any code requirement for the smoke hatches in the large warehouse. I have never came across for such requirement in any of my previous project but previous consultant has proposed smoke hatches in the roof of warehouse. I believe these smoke hatches to be interlocked with fire alarm...