Phyiscal Security Flashcards
Blackout
prolonged loss of power.
Fault
Short loss of power.
Brownout
prolonged low voltage.
Sag
temporary low voltage.
Surge
prolonged high voltage.
Spike
temporary high voltage.
Lumen
the amount of light one candle creates.
Light was historically measured in foot-candles; one foot-candle is one lumen per square foot.
Lux
one lux is one lumen per square meter.
Smoke detector example
1) Ionization-based smoke detectors
2) Photoelectric sensors
Humidity level
- levels of 40-55% are recommended.
- Humidity creates electrostatic discharges.
- A commonly recommended “set point” temperature range for a data center is 68-77 F (20-25 C).
Traverse-mode noise
is a type of EMI generated by the electrical charge difference between hot and neutral electric wires.
Deluge
are similar to dry pipes, except the sprinkler heads are open and larger than dry pipe heads.
The pipes are empty at normal air pressure; the water is held back by a deluge valve. The valve is opened when a fire alarm triggers.
Class A fires
are common combustibles such as wood, paper, cloth, rubber, plastics, etc.
Extinguished with water or soda acid.
Class B fires
are burning alcohol, oil, grease, flammable gases and gasoline.
Extinguished with CO2, Halon, gas or soda acid.
You should never use water to extinguish a class B fire.
Class C fires
are electrical fires.
Extinguishing using Halon or CO2 or carbon dioxide. Never use soda acid.
Class D fires
are burning metals
Extinguished with dry powder.
Class K fires
are kitchen fires, such as burning oil or grease. Wet chemicals are used to extinguish class K fires.
Gates
o Class I: Residential (home use)
o Class II: Commercial/General Access (parking garage)
o Class III: Industrial/Limited Access (loading dock for 18-wheeler trucks)
o Class IV: Restricted Access (airport or prison)
Crime Prevention through Environmental Design (CPTED)
o a crime reduction technique that applicable to the analysis of the building function and site design against physical attack.
o CPTED process provides direction to solve the challenges of crime with organizational (people), mechanical (technology and hardware), and natural design (architecture and circulation flow) methods.
Natural surveillance
- includes security guards, CCTV, line of sight, low-level landscaping, and raised entrances.
The primary concern is to ensure that criminals feel uncomfortable making an attack.
Natural access control
- includes door, fence, lighting, and landscaping placement.
- Ensures that access and traffic to building entrances is controlled.
Territorial reinforcement
- includes walls, fences, landscaping, lighting, flags, and sidewalks
- emphasize or extend the company’s area of influence so users feel that they own the area.
Key locks: two types of mechanical locks are
warded locks and tumbler locks
three types of tumbler locks
pin, wafer, and level tumbler locks
Flame detectors and they are classified as
classified as infrared (IR) and ultraviolet (UV) detectors
ultraviolet (UV) flame detectors
detect flames at speeds of 3–4 milliseconds due to the high-energy radiation emitted by fires.
One drawback: requires line-of-sight to detect the flame
infrared (IR) flame detector
- detect a large mass of hot gases
- these patterns are sensed with a thermographic camera and an alarm is sounded.
- Additional hot surfaces in the room may trigger a false response with this alarm
Heat detectors
- Include fixed temperature.
- It requires to check for battery life and operation status.
- It should not be used to replace smoke detectors.
Ionization-based smoke detectors
monitors the air around the sensors constantly. Once there is enough smoke in the room, the alarm will sound.
Photoelectric smoke sensors
contain an LED (Light-Emitting Diode) and a photoelectric sensor that generates a small charge while receiving light.
fire suppression agents work via four methods
- Halon disrupts the chemical reaction of a fire.
- CO2 displaces the oxygen.
- Water reduces the temperature.
- Soda acid removes the fuel. float on the surface of some liquid fires, starving the oxygen supply.
Which facet in the CPTED approach includes security guards, closed-circuit television (CCTV), line of sight, low landscaping, and raised entrances?
natural surveillance
Which facet in the CPTED approach includes door, fence, lighting, and landscaping placement?
natural access control
Which facet in the CPTED approach includes walls, fences, landscaping, lighting, flags, and sidewalks that emphasize or extend the company’s area of influence?
territorial reinforcement
In which proper order should the steps below be taken after electronic equipment or media has been exposed to smoke contaminants?
o Turn off power to equipment.
o Move equipment into an air-conditioned and humidity controlled environment.
o Spray connectors, backplanes, and printed circuit boards with Freon or Freon-alcohol solvents.
o Spray corrosion-inhibiting aerosol to stabilize metal contact surfaces.
In which proper order should the steps below be taken after electronic equipment or media has been exposed to water?
o Turn off all electrical power to the equipment.
o Open cabinet doors and remove panels and covers to allow water to run out.
o Place all affected equipment or media in an air-conditioned area, if portable.
o Wipe with alcohol or Freon-alcohol solutions or spray with water-displacement aerosol sprays.
what type control is light?
detective and deterrent
what type control is CCTV?
detective
What is depth of field and field of view?
depth of field (the area that is in focus) and
field of view (the entire area viewed by the camera).
photoelectric motion sensor
sends a beam of light across a monitored space to a photoelectric sensor. The sensor alerts when the
light beam is broken.
What is the alternatives to glass windows?
polycarbonate and acrylic
What control are dogs?
deterrent and detective
primary drawback to using dogs as a perimeter control is legal liability
What is Topography?
is the physical shape of the land: hills, valleys, trees, etc.
Topography can be used to steer ingress and egress
to controlled points
How to mitigate crosstalk?
Never route power cables close to network cables.
What cause false alarms to smoke detectors?
small airborne dust particles can trigger smoke detectors.
What is the drawback to Flame detector?
requires a line of sight to detect the flame; smoke detectors do not have this limitation.
Duress warning systems
designed to provide immediate alerts to personnel in the
event of emergencies, such as sever weather, threat of violence, or chemical contamination.
Four elements must be present in order for fire to exist are
HEAT, FUEL, OXYGEN and CHAIN REACTION
In Sprinkle system, what is the purpose of the colors in the bulbs?
indicating the ceiling temperature that will trigger the bulb to burst and open the sprinkler head.
EMI can be caused by
lightning, motors, and the current difference between wires.
RFI can be caused by
electrical system mechanisms, fluorescent lighting, and electrical cables.
What is the best use of capacitance sensor?
are used to for spot protection within a few inches of the object, rather than for overall room security monitoring.
What is the best use of wave pattern motion sensor?
it generate a wave pattern and send an alarm if the pattern is disturbed.
It is used for spot protection within a few inches of the object, rather than for overall room security monitoring.
Polycarbonate acrylic windows
are more resistant to breakage than standard plate windows due to acrylic materializes.
Acrylic materializes give toxic fumes in a fire situation.
Glass-clade polycarbonate windows are
the strongest windows available. They are resistant to breakage, chemicals, fires, and abrasions. Extremely expensive.
