PEC CHAPTER 5 SPECIAL OCCUPANCIES Flashcards
Reference Standards of Hazardous Locations
National Fire Protection Association (NFPA)
American Petroleum Institute (API)
Instrumentation Systems and Automation Society (ISA)
Locations have been classified depending on the properties of the flammable vapors, liquid, or gasses, or combustible dusts or fibers that may be present.
HAZARDOUS LOCATIONS
Flammable gases or vapor are present in air which is sufficient to produce explosive or ignitable mixtures.
CLASS I LOCATIONS
a) Ignitable concentrations of flammable gases or vapors can exist.
b) Existence of gas due to frequent repair or maintenance operation or because of leakage.
c) Release of such gasses due to breakdown, failure or faulty operation of equipment.
CLASS I, DIVISION 1
a) Volatile flammable liquids or flammable gases are handled, processed, but in which liquids and gases are confined and can escape only in case of accidental rupture or breakdown, or such abnormal operation.
b) Mechanical ventilations prevent ignitable concentrations of gases or vapors and failure or abnormal operation might become hazardous.
c) Gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air
CLASS I, DIVISION 2
Locations that has presence of combustible dust.
CLASS II LOCATIONS
a) Combustible dust is in the air under normal operating conditions.
b) Where mechanical failure of abnormal operation of machinery or equipment might cause such explosive or ignitable mixtures to be produced.
c) Group E combustible dusts may be present in quantities sufficient to be hazardous.
CLASS II, DIVISION 1
a) Presence of combustible due to abnormal operations
b) Dust accumulations are present in normal operation but are insufficient to be hazardous but infrequent malfunctioning of handling/processing equipment it would be hazardous
CLASS II, DIVISION 2
Locations that has the presence of ignitable fibers or flyings.
CLASS III LOCATIONS
Ignitable fibers are handled, manufacture or used.
CLASS III, DIVISION 1
Ignitable fibers are stored, handled and manufactured
CLASS III, DIVISION 2
MATERIAL GROUPS
MESG
Maximum Experimental Safe Gap
MATERIAL GROUPS
MIC
Minimum Igniting Current Ratio
MATERIAL GROUPS
CLASS I GROUP CLASSIFICATIONS
Acetylene
Group A-
MATERIAL GROUPS
CLASS I GROUP CLASSIFICATIONS
Flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, MESG value is less than or equal 0.45 mm, MIC ratio is less than or equal to 0.40 mm.
Group B
MATERIAL GROUPS
CLASS I GROUP CLASSIFICATIONS
Flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, MESG value is greater than 0.45 mm and less than or equal to 0.75 mm, MIC ratio than 0.40 and less than or equal to 0.80.
Group C
MATERIAL GROUPS
CLASS I GROUP CLASSIFICATIONS
Flammable gas, flammable liquid-produced vapor, or combustible liquid-produced vapor mixed with air that may burn or explode, MESG value > 0.75 mm, MIC ratio > 0.80.
Group D
MATERIAL GROUPS
CLASS II GROUP CLASSIFICATIONS
Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloys, or other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment
Group E
MATERIAL GROUPS
CLASS II GROUP CLASSIFICATIONS
Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrapped volatiles. Carbonaceous dust ex. Coal, carbon black, charcoal, and coke dusts.
Group F
MATERIAL GROUPS
CLASS II GROUP CLASSIFICATIONS
Atmospheres containing combustible dusts not included in Group E or F, including flour, grain, wood, plastic, and chemicals.
Group G
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Encloses the parts w/c could ignite the atmosphere by sparking or heating.
Encapsulation “m.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection
- Enclosure can withstand an internal explosion of flammable mixture that has penetrated into the interior, without suffering damage and w/o causing ignition in joints or openings.
Flameproof “d.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Applied to electrical equipment that does not produce arcs in normal service and under specified abnormal conditions, increased security is given against the possibility of excessive temperatures and of the occurrence of arcs and sparks.
Increased Safety “e.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Any spark or thermal effect is incapable of causing ignition of a mixture of flammable or combustible material in air under prescribed test conditions.
Intrinsic Safety “i.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Electrical equipment is immersed in a protective liquid in such a way that an explosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited.
Oil Immersion “o.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Electrical parts capable of igniting an explosive atmosphere are fixed in position and completely surrounded by filling material (glass or quartz powder) to prevent the ignition of an external explosive atmosphere
Powder Filling “q.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Types of Protection:
- Electrical equipment, in normal operation, is not capable of igniting a surrounding explosive gas atmosphere and a fault capable of causing ignition is not likely to occur.
Type of Protection “n.”
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Classification of Locations:
a) Ignitable concentrations of flammable gas/vapors are not likely to occur under normal conditions; but if they do, will exist only for short period
b) Volatile flammable liquids or flammable gases are handled, processed, but in which liquids and gases are confined and can escape only in case of accidental rupture or breakdown, or such abnormal operation.
Class I, Zone 2
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Classification of Locations:
- Ignitable concentrations of flammable gases or vapors are present continuously or for long periods of time
Class I, Zone 0
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Classification of Locations:
a) Ignitable concentrations of flammable gas/vapors may exist under normal conditions
b) Ignitable concentrations of flammable gas/vapors may exist because of repair/ maintenance
c) Equipment breakdown or faulty operation could result in the release of ignitable concentrations of flammable gas/vapors
Class I, Zone 1
CLASS I, ZONE 0, 1, AND 2 LOCATIONS
Zone Equipment Marking
Equipments shall be marked with all the following in the order shown: (6)
a) Class
b) Zone
c) Symbol ―AEx‖
d) Protection technique(s)
e) Applicable gas classification group(s)
f) Temperature classification
ZONE 20, 21, AND 22 LOCATIONS
- An area where combustible dust or ignitable fibers and flyings are present continuously or for long periods of time in quantities sufficient to be hazardous
Zone 20 Hazardous (Classified) Locations
ZONE 20, 21, AND 22 LOCATIONS
- An area where combustible dust or ignitable fibers and flyings are likely to exist occasionally under normal operation in quantities sufficient to be hazardous.
Zone 21 Hazardous (Classified) Locations
ZONE 20, 21, AND 22 LOCATIONS
- An area where combustible dust or ignitable fibers and flyings are not likely to occur under normal operation in quantities sufficient to be hazardous.
Zone 22 Hazardous (Classified) Locations
HEALTH CARE FACILITIES
General Care Areas
- Shall be supplied by at least 2 branch circuits, one for the emergency system and the other for the normal system.
Patient Bed Location
HEALTH CARE FACILITIES
General Care Areas
Patient Bed Location Receptacles - Shall be provided with a minimum of ______________ either a single or duplex types or a combination of both. All receptacles, whether four or more, shall be listed ―hospital grade‖ and so identified.
4 receptacles
HEALTH CARE FACILITIES
General Care Areas
__________ Receptacles located within the rooms, bathrooms, playrooms, activity rooms, and patient care areas of pediatric wards shall be listed ___________
Pediatric Locations
tamper resistant.
HEALTH CARE FACILITIES
Critical Care Areas
Each branch of the emergency system and each equipment system shall have one or more______________. One transfer switch shall be permitted to serve one or more branches or systems in a facility with a maximum demand on the essential electrical system of __.
transfer switches
150 KVA
HEALTH CARE FACILITIES
Critical Care Areas
- Shall be supplied by at least _________, one for the emergency system and the other for the normal system. At least_ branch circuit from emergency system shall supply an outlet(s) only at that bed location.
Patient Bed Location Branch Circuits
2 branch circuits
1
HEALTH CARE FACILITIES
Critical Care Areas
Patient Bed Location Receptacles
- Shall be provided with a minimum of____ and listed
―hospital grade‖. Each receptacle shall be grounded by _____ equipment grounding conductor.
6 receptacles
copper
HEALTH CARE FACILITIES
Critical Care Areas
- Ground-fault circuit-interrupter protection for personnel shall not be required for receptacles installed in those critical care areas where the ________(2) are installed within the patient room.
toilet and basin
HEALTH CARE FACILITIES
Critical Care Areas
Patient Vicinity Grounding and Bonding (Optional) - An equipment bonding jumper not smaller than __________ shall be used to connect the grounding terminal of receptacles.
5.5 mm2 (2.6 mm dia.)
HEALTH CARE FACILITIES
Critical Care Areas
- Equipment grounding conductor for special-purpose receptacles, such as operation of mobile X-ray equipment, shall be extended to the ___________ of the branch circuits.
Special-Purpose Receptacle Grounding
reference grounding points
HEALTH CARE FACILITIES
Task Illumination and Selected Receptacles for Critical Branch
- The _________ of the emergency system shall supply power for task illumination, fixed equipment, selected receptacles, and special power circuits serving the following areas and functions related to patient care:
critical branch
HEALTH CARE FACILITIES
Task Illumination and Selected Receptacles for Critical Branch (9)
- Critical care areas that utilize anesthetizing gases
- The isolated power systems in special environments
- Patient care areas - task illumination and selected receptacles in the following:
a. Infant nurseries
b. Medication preparation areas
c. Pharmacy dispensing areas
d. Selected acute nursing areas
e. Psychiatric bed areas (omit receptacles)
f. Ward treatment rooms
g. Nurses’ stations (unless adequately lighted by corridor luminaires) - Additional specialized patient care task illumination and receptacles, where needed
- Nurse call systems
- Blood, bone, and tissue banks
- Telephone equipment rooms and closets
- Task illumination, selected receptacles, and selected power circuits for the following:
a. General care beds (at least one duplex receptacle per patient bedroom)
b. Angiographic labs
c. Cardiac catheterization labs
d. Coronary care units
e. Hemodialysis rooms or areas
f. Emergency room treatment areas (selected)
g. Human physiology labs
h. Intensive care units
i. Postoperative recovery rooms (selected) - Additional task illumination, receptacles, and selected power circuits needed
ASSEMBLY OCCUPANCIES
- Assembly occupancies shall include, but not be limited to, the following:
Armories Assembly Halls Auditoriums Bowling lanes Club rooms Conference rooms Courtrooms
Dance halls
Dining and drinking facilities Exhibition halls Gymnasiums
Mortuary chapels Multipurpose rooms Museums
Places of awaiting transportation Places of religious worship
Pool rooms Restaurants Skating rinks
ASSEMBLY OCCUPANCIES
Temporary Wiring- Flexible cables and cords approved for hard or extra-hard usage shall be permitted to be _______ where protected from contact by the general public
laid on floors
ASSEMBLY OCCUPANCIES
Wiring in General- The fixed wiring methods shall be metal raceways, flexible metal raceways, nonmetallic raceways encased in not less than ____(mm) of concrete, Type MI, MC, or AC cable with an insulated EGC.
50 mm
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
Wiring Methods
The fixed wiring method shall be metal raceways, nonmetallic raceways encased in at least ____(mm) of concrete Type __________(3) containing an insulated equipment grounding conductor
50 mm
MI cable, MC cable, or AC cable
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
Dressing Rooms
___________ shall not be installed in dressing rooms.
Pendant lampholders
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
Dressing Rooms
Lamp Guards - All exposed incandescent lamps in dressing rooms, where less than _______(mm) from the floor, shall be equipped with ________ riveted to the outlet box cover or otherwise______ in place.
2 400 mm
open-end guards
sealed or locked
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
Dressing Rooms
Switches Required - All lights and any receptacles adjacent to the mirror(s) and above the dressing table counter(s) installed in dressing rooms shall be controlled by _______ installed in the dressing room(s). Each switch controlling receptacles ______ to the mirror(s) and above the dressing table counter(s) shall be provided with a _____ located ____ the dressing room, ______ to the door to indicate when the receptacles are ______.
wall switches
adjacent
pilot light
outside
adjacent
energized
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
CARNIVALS, CIRCUSES, FAIRS, AND SIMILAR EVENTS
Overhead Conductor Clearances
Amusement rides and amusement attractions shall be maintained not less than _____(mm) in any direction from overhead conductors which are rated _____V, nominal, less or higher
4500 mm
600V
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
CARNIVALS, CIRCUSES, FAIRS, AND SIMILAR EVENTS
Disconnecting Means
Each ride and concession shall be provided with __________ or ________ located within sight and within ______(mm) of the operator’s station
fused disconnect switch
circuit breaker
1800 mm
THEATERS, AUDIENCE AREAS OF MOTION PICTURE AND TELEVISION STUDIOS, PERFORMANCE AREAS, AND SIMILAR LOCATIONS
CARNIVALS, CIRCUSES, FAIRS, AND SIMILAR EVENTS
Portable Distribution or Termination Box
Where installed outdoors, the box shall be of ______ construction and mounted so that the bottom of the enclosure is not less than _____(mm) above the ground.
weatherproof
150 mm
MOTION PICURE AND TELEVISION STUDIOS AND SIMILAR LOCATIONS
Permanent Wiring
Shall be Type _________(2) containing equipment grounding.
MC Cable, Type AC cable
MOTION PICTURE PROJECTION ROOMS
Work Space
Each motion picture projector, floodlight, spotlight, or similar equipment shall have clear working space not less than _____(mm) on each side and at the rear thereof.
800 mm wide
MOTION PICTURE PROJECTION ROOMS
Conductor Size
Conductors supplying outlets for ______ projectors of the professional type shall not be smaller than __________(mm2) and shall be of sufficient size for the projector employed.
arc and xenon
8.0 mm2
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
_________________________Shall not be required to meet the provisions for the number or capacity of circuits required.
Mobile Homes Not Intended as Dwelling Unit
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Power Supply
Feeder - Not more than one listed ___A mobile home power supply cord with an integrally molded or securely attached plug cap or a permanently installed feeder.
50A
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Power Supply
Attachment Plug Cap -
Shall be a 2-pole, 3-wire, grounding type, rated 50 amperes, 250 volts or 3- pole, 4-wire, grounding type, rated 50 amperes, 125/250 volts and intended for use with the 50- ampere, 250-volt and 125/250-volt receptacle.
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Power Supply
Overall Length of a Power-Supply Cord
- Shall not be less than ______(mm) and shall not exceed
__m - The length of the cord from the face of the attachment plug cap to the point where the cord enters the mobile home shall not be less than ______m
6400 mm
11 m
6000 m.
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Marking
- The power-supply cord shall bear the following marking:
―FOR USE WITH MOBILE HOMES - 40 AMPERES‖
or
―FOR USE WITH MOBILE HOMES - 50 AMPERES
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Point of Entrance
- The point of entrance shall be in the _________(3)
exterior wall, floor, or roof
MOBILE HOMES, MANUFACTURED HOMES, AND MOBILE PARKS
Protected
- Shall be permitted to be installed within the mobile home walls, provided a continuous raceway having a maximum size of _______(mm) is installed from the________ to the _______ of the mobile home floor.
30 mm
branch-circuit panelboard
underside
RECREATIONAL VEHICLES AND RECREATIONAL VEHICLE PARKS
Means for Connecting to Power Supply
Cord - The cord exposed usable length, measured to the point of entry on the vehicle exterior, shall be a minimum of __________(mm) where the point of entrance is at the side of the vehicle or shall be a minimum __________(mm) where the point of entrance is at the rear of the vehicle
7600 mm
9000 mm
RECREATIONAL VEHICLES AND RECREATIONAL VEHICLE PARKS
Means for Connecting to Power Supply
Label at Electrical Entrance - Shall have permanently affixed to the exterior skin, at or near the point of entrance of the power-supply cord(s), a label _______(mm x mm) minimum size, made of etched, metal-stamped, or embossed brass, stainless steel, or anodized or alum/clad >_________.
75 mm × 45 mm
0.50 mm thick
THIS CONNECTION IS FOR 115/230VOLT AC, 3-POLE, 4-WIRE, 60 HZ, AMPERE SUPPLY
RECREATIONAL VEHICLES AND RECREATIONAL VEHICLE PARKS
Means for Connecting to Power Supply
d) Location - The assembly shall be located within ________(mm) of the rear, on the left (road) side or at the rear, left of the longitudinal center of the vehicle, within ______ (mm) of the outside wall.
4500 mm -rear
460 mm - outside wall
FLOATING BUILDING
_____________________Shall be located adjacent to, but not in or on, the building or any floating structure.
Location of Service Equipment
FLOATING BUILDING
Feeder Conductors
Each floating building shall be supplied by a ____ set of feeder conductors from its ________.
single
service equipment
MARINAS AND BOATYARDS
- An enclosed assembly that can include receptacles, circuit breakers, fused switches, fuses, watt-hour meter(s), and monitoring means approved for marine use.
Marine Power Outlet
MARINAS AND BOATYARDS
Distribution System
- Yard and pier distribution systems shall not exceed _______V phase to phase
600 volts
MARINAS AND BOATYARDS
Electrical Connections
- All electrical connections shall be located at least ______(mm) above the deck of a floating pier. All electrical connections shall be located at least ______(mm) above the deck of a fixed pier but not below the electrical datum plane
300 mm
300 mm
MARINAS AND BOATYARDS
Electrical Datum Plane
- In land areas subject to tidal fluctuation, the electrical datum plane is a horizontal plane _____ (mm)above the highest tide level for the area occurring under normal circumstances, that is, highest high tide.
- The electrical datum plane for floating piers and landing stages are the following:
a) Installed to permit ______ response to water level, without __________.
b) A horizontal plane _________ (mm) above the water level at the floating pier or landing stage and a minimum of _____(mm) above the level of the deck.
600 mm
rise and fall
lateral movement
800 mm
300 mm
.
.
