AH23101.docx - FIRE SCIENCE FIRE SCIENCE Student name...

This preview shows page 1 - 4 out of 11 pages.

FIRE SCIENCE FIRE SCIENCE Student name Course Professor University Date
Image of page 1

Subscribe to view the full document.

FIRE SCIENCE 2 Task 1 Photoelectric smoke detectors are highly recommended for electrical risers locations due to the fact that they are more responsive to fires which start with a long period of smoldering (also known as smoldering fire) (Machado Tavares, 2014). In addition, they are very effective and this is mainly based on their principle of operation. They aim a light source into the sensing chambers at an angle away from the sensor. When smoke enters the chambers, light is reflected onto the light sensor thus activating the alarm in the smoke detector. Moreover, the most significant parameter in any fire detector is time of response. As such, owing to this factor, photoelectric smoke fire detectors are strongly recommended for because of usage conveniences in for electrical risers locations. Also, photoelectric detectors have proved to be effective and also economical for the protection of large electrical riser locations especially when the access to point smoke for maintenance would bring up practical challenges. The photoelectric detectors do not flex due to changes in temperature or even imposed loads which might result in misalignment of the photons causing false signals or alarms. Carbon monoxide (CO) is not advised for use in detection of fire in ceiling or roof void difficult areas. This is because such detectors go into an alarm when they sense certain amount of carbon monoxide in the air over a given amount of time (Culhane, 2011). As such, they could be immune to some given environmental influences which may result in false alarms for some smoke detection systems such as ceiling and roof void difficult access. In addition, their rate of response to fires in such location is not appreciably fast. Furthermore, carbon monoxide detectors do not require to be ceiling mounted, that is they should be mounted at levels which are relatively low about a space that is highly protected, wherein they can be able to detect very large
Image of page 2
FIRE SCIENCE 3 fires. This is why carbon detectors are not advised for ceiling or roof voids difficult access locations. Task 2 The four gases selected whose lower flammability limit is to be determined are acetaldehyde, acetylene, acetic acid and 1, 3- Butadiene. Considering a mixture of 20% acetaldehyde, 25% acetylene, 30% acetic acid and 25% 1,3- butadiene, the mixture is flammable yet not potentially explosive. Taking the lower flammability limit of the gases as: LFL for acetaldehyde as 4 LFL for acetylene as 2.5 LFL for acetic acid as 4 LFL for 1,3- Butadiene as 2 Then the lower flammability limit of the mixture can be calculated by using equation 1 because it can be used as a good estimation for mixtures of the flammable gases identified (Karlsson and Quintiere, 2000).
Image of page 3

Subscribe to view the full document.

Image of page 4
  • Fall '16
  • Prof Datuk Dr Shahrin
  • Combustion, Active fire protection, Fire extinguisher, Smoke detector

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern