nicet fire alarm level 1 pop quiz

According to NFPA 72, If guards, covers, or lenses are employed, they shall ____________________. If someone is wearing a seatbelt, her body will tend to move with the car seat. if a combination audible/visible appliances are installed, the location of the installed appliance shall be determined by the requirements of, what is the maximum number of 12-gaugeTHHN conductors that can be installed in 1-inch EMT. how often must manual fire alarm boxes be tested? An initiating device in which the sensing element is designed to be destroyed in the process of operation, is of what type? Simply select the NICET exam or fire protection discipline you're studying for and begin your free sample test! How many years after the initial installation shall all fixed temperature non restorable line type detectors be replaced or have 2 per 100 laboratory tested? WHEN INSTALLING LOBBY SMOKE DETECTORS FOR ELEVATOR RECALL WHAT IS THE MAXIMUM DISTANCE THEY MUST BE FROM THE CENTER LINEOF THE ELEVATOR DOOR? True or False smoke detectors in a 1 and 2 family dwelling do not require a calibrated sensitivity test. NICET Level II Fire Alarm Certification is required as much of the work will be on US Government properties. and what are there multipliers? The archiving of all required test inspection records _____________ shall be permitted if a written copy of these records can be provided promptly, when requested? Were non-power limited wiring is installed exposed, it must be mechanically protected within _______ of the finished floor, According to NFPA 72, visible notification of plans for non-sleeping areas must be mounted between _____ and _____ inches above the finished floor. Why are NICET Practice Tests Only Half the Battle? We have up to date information on the newest fire alarm trends such as fire service access elevators, mass notification, voice intelligibility, occupant evacuation elevators and two-way communication for Areas of Refuge. When using a cellular transmission service as a DACT's secondary transmission channel how often must its verification (test) signal be transmitted to the remote supervising station? Or for _____ minutes in full alarm directly after power fails. Installation personnel shall be qualified or shall be supervised by persons who are qualified in the installation inspection and testing of fire alarm systems. Using the index we arrive at the keyword: Notification Appliance -> Protection 18.3.4 to find the answer: (a). With the circuit disconnected from power, the positive leg of a fire alarm circuit is metered to a known ground with the meter set to the 10kohm setting. . Introducing Cram Folders! After one year and every alternate year thereafter. Contact Us. Getting familiar with what code is where, is how you pass the nicet 1 and 2 tests. ANSI S3.41. When testing a balanced circuit where metallic continuity is not present in connection with a McCulloh transmitter, which transmission channel fault condition does not have to be verified? FIRE ALARM SYSTEMS SHALL HAVE SUFFICIENTBATTERY BACK-UP TO OPERATE THE SYSTEM FOR ______ HOURS OF STAND-BY AND _____ MINUTES OF ALARM. This condition is known as __________. *This exam contains a 30-minute break. When are appliances sounding the ANSI S3.41 standard audible evacuation signal required to be synchronized? Explain. Indication of the DACT trouble signal occurs at the premises fire alarm control unit within 4 minutes of detection of the fault. This is a video response answer to one of the Pop Quiz question firealarmscertified.com website.NICET Fire Alarms Level I Study Guidehttp://firealarmscertifi. NFPA 72 requires smoke detectors, installed to provide smoke control using a FACP powered relay for controlling the associated HVAC fans and dampers, to be ______________. According to NFPA 72, the mounting height of a strobe light is between ___________ inches and __________ inches above finished floor. Students attending this course will develop a strong understanding of fire alarm systems, including the requirements of NFPA 72 (National Fire . Consulting keyword Smoke Detectors, leads us to Smoke Detectors -> Installation17.7.1.4 to 17.7.1.11. Put the meter in series with the circuit (Pulling negative wire and replacing it with voltmeter to read current). Some questions include a graphic or document to be viewed by clicking on the exhibit button. This prep book includes 150 questions referencing NFPA 72 2016, NEC 2014, IBC 2015, OSHA standards, project management guides and technical/theoretical disciplines. True or False. Give the formula of a complex constructed from one Ni2+\mathrm{Ni}^{2+}Ni2+ ion, one ethylenediamine ligand, three ammonia molecules, and one water molecule. 18 AWG conductors that can be enclosed in a 4" x 1 1/4" square metal junction box? Ensure that there are no changes that affect equipment performance. Consider that the circuit is properly functioning. Topics also include fire alarm system programming and technical tips. One corresponds to a head-on collision, the other to a rear-end collision. True or False, When performing a re-acceptance test after changes to site specific software the system executive software must also be upgraded. Which is which? Monitored fire alarm systems employing automatic fire detectors or waterflow detection devices, must also provide? HOW MANY CONDUITS CAN BE CONNECTED TO ONE SEISMICWIRE? This means that you have either worked for a company whose direct market is Fire Alarm Systems, or you have done inspections, service, construction or engineering of some sort for a total of 3 months. (b) verified to be operating in accordance with the listed sensitivity. B. not less than 4 feet, and not more than 5 feet. Welcome to the NICET Fire Alarm Systems Sample Test! During an annual test of a fire alarm system, you simulate a detectors operation. nicet fire alarm level 1 pop quiz. The operable part of each manual fire alarm box shall not be less than _________ and not more then ___________ above floor level? Inspection & Testing of Fire Alarm Systems Exams: Level I Exam: 84 questions, 110 min. Please select the correct language below. Confusion B. Cram.com makes it easy to get the grade you want! Press Start Quiz to begin. D PER THE MANUFACTURERS INSTRUCTIONS AND CLASSIFICATIONS, A EXPLANATORY INFORMATION FOLLOWS IN THE APPENDIX, B AN EXCEPTION TO THE REQUIREMENT FOLLOWS, C A CHANGE IN INFORMATION FROM LAST CODE EDITION, D SEE UL STANDARDS FOR DETAILED EXPLANATIONS, C MARKED WITH FIRE ALARM CIRCUIT CONTROL, C WITHIN 1/2 THE LISTED SPACING OF THE PEAK, D WHEN THERE IS A POTENTIAL FOR FALLING OBJECTS. This study guide has been updated to the latest codes and standards: NFPA 70 2014, NFPA 72 2016, NFPA 101 2015, IBC 2015. The Fire Alarm Systems Level I exam is available to be administered online with a remote proctor. Which function shall be tested for each newly installed smoke detector? I do not want you using the binder to find answers. You can purchase the Fire Alarms Online NICET Practice Test to the left via the secure PayPal checkout. The verification of proper operation of a UPS system dedicated to a fire alarm system and used as a required fire system power source shall be in accordance with: True or False: Test plans are suggested for use by the T&I personnel, but are not required? Smoke detectors shall not be installed in what ambient temperatures? Monitoring for integrity is not required for the circuit of an alarm notification appliance installed __________ . In short, the NICET practice exams should not only get your ready for your exam, but make you comfortable in using your references on the job. An inspectors test connection is used when properly testing a ___________. How often are digital alarm communicator transmitters required to be inspected? How often shall sealed led acid batteries be replaced? P1\mathscr{P}_{1}P1 and P2\mathscr{P}_{2}P2 are orthogonal if n1\mathbf{n}_{1}n1 and n2\mathbf{n}_{2}n2 are orthogonal and parallel if n1\mathbf{n}_{1}n1 and n2\mathbf{n}_{2}n2 are parallel. NICET now has two Fire Alarm Certifications. NICET certification is mandated in nearly three-quarters of U.S. statesand by a wealth of local jurisdictions in the othersfor technicians responsible for the design of water-based fire sprinkler systems such as standpipes and fire sprinklers, and/or inspection, testing, and maintenance (ITM) of water-based systems. The circuit has an end of the line resistor with a value of 4.7ohms. The manufactures published instructions and NFPA 72. Try looking the answers up for Fire Alarm Level I. and another for Fire Alarm Level II. You must sign in or sign up to start the quiz. Add to folder Therefore, doing poorly in several specific subject areas will cause you to fail the test and the entire test will have to be re-taken. Just follow the same process as detailed above. c. the value of the resistor voltage exactly one time constant after S1S_1S1 is moved to Position 111? While testing a fire alarm system you remove a two-wire smoke detector from its plug-in base on a Class B type circuit. Fire Tech is recognized by NICET and has helped numerous students pass their NICET . All rights reserved. All rights reserved. Mass notification systems functions shall be tested for which of the following three things: Circuit Supervision, Correct receipt of alarms, Receipt of alarm, troubles and supervisory conditions at the supervising station. Our F.A.C.T.S. When maintaining equipment, it is important to identify deteriorating conditions. Nerfshinobi. Below is a question to help you prepare for the actual NICET certification Fire Alarm Systems exam. Below is another pop quiz question to help you prep for the NICET Certification Fire Alarm System exam. A charger test of a lead-acid battery with a voltmeter shall confirm that the voltage per cell is __________ volts at ___________ degrees F. What type of training/ cert is intended to allow individuals to service a specific brand of fire alarm equipment for which they have been trained? According to NFPA 72, how many detectors will be needed to protect this room? How is the alarm switch of a fire extinguishing system or supression system tested? NICET FIre Alarm Inspections. What is the required testing frequency of a radiant energy type fire detector? Is anything really "sucking"? Sets found in the same folder. Why Fire Alarm Installation Methods? NICET Fire Alarms Level 1 Study Guide Intro. Verification of performance of inspection and testing programs shall do which of the following to. I acknowledge that divulging the contents of this examination to others in any manner is expressly forbidden and may subject me to sanctions.. True - Just use the Orange dust covers they come packed with. The report also states that in 100 house fires the death rate was twice as high in home with no or non-working homes; and that in homes with smoke detectors As I furiously flipped through the Contents section in Brett Lacey and Paul Valentines Fire Prevention Applications, pages vacillated hither and thither hi Bob / Cary The Fire Alarm Systems certification is a robust credential, based on inter-related elements of system design, installation, maintenance, and inspection. Question: Where detectors are installed but not operational during construction, they shall be __________________________________. 30 terms. Sample NICET Special Hazards Systems Practice Test. Questions may have more than one correct answer, but in those cases, you will be told how many answers to choose. These devices are wired into a central control panel. You must specify a text. False, NFPA 72 stated that testing is done by removal of the link and operating the device. 2023 Fire Alarms Certified. Browse 459 NICET FIRE ALARM jobs ($52k-$99k) from companies with openings that are hiring now. What alarm capability would you expect from the other detectors on that circuit? The heat detector is listed for a maximum space between detectors of 30 feet. 2023 Fire Alarms Certified. Get Certified Now! According to NFPA 72, defects in fire alarm systems which are not able to be corrected during regular testing and maintenance, shall be cause to notify the__________. ,:&B "\K7tuJ!5$'3KJT #1,; PK ! 2023 Fire Alarms Certified. The "suction cup" is a common device used to suspend pictures, plants, and other objects from walls, ceilings, windows, and other smooth surfaces. Heat gun or some other approved heating device, Indicates a recommendation or that which is advised but not required, NICET Level 1 Fire Inspection & Testing of Wa, Fundamentals of Engineering Economic Analysis, David Besanko, Mark Shanley, Scott Schaefer, Theory and Design for Mechanical Measurements. Conductors returning to the fire alarm control panel from the last field device on the circuit might indicate a _________ circuit. 3.5 (2 reviews) Flashcards. How might this change in temperature affect the intensity of the storm? (with one obvious exception). Diagram. What must be done when using a multimeter to measure current? If a defect or malfunction is not corrected at the conclusion of system inspection, testing, or maintenance, the responsible party shall be informed of the impairment _______. While working on a Large Group B building I encountered a number of devices (smoke detectors) with dust/debris covers. Each test session begins with a tutorial allowing you to get used to the process. 2017. Consider the use of a multimeter in troubleshooting a fire alarm circuit. Assume that the capacitor in Fig. NTC's NICET Level I Fire Alarm class is intended for the low voltage professional. When a heat test is performed on a restorable line type heat detector, the detector must activate within_________. Term. Detection devices are dispersed throughout a building. Make sure this account has posts available on instagram.com. Where must the record of completion be kept? A minimum of 2 years of fire detection and signaling systems experience which MUST include: At least 12 months of fire alarm systems experience, including alarm and detection, notification, sprinkler monitoring, and interfaces and controls for agent . Applicants with a disability as defined in Title III of the Americans with Disabilities Act who may be placed at a disadvantage when taking a NICET certification examination may request a testing accommodation by contacting test@nicet.org prior to scheduling testing. Teaches the code knowledge and practical technical skills you need to design, install and maintain fire alarm systems that comply with NFPA 72 (2019 edition) Prepares students for NICET Level 1 and 2 examinations and to satisfy one of the key requirements for the ESA NTS Certified Alarm Technician - Level II Who is responsible for maintaining Personal Protective Equipment? And what is the color code requirement for a spot type heat detector rated at 200F, I unless otherwise recommended by manufacture is published instructions, single and multiple stations smoke alarms installed in one and two family dwellings should be replaced every. Nicet Level 1 Fire Alarm Inspection & Testing. 14 conductors of type THHN that may be installed in 1/2" electrical tubing (EMT)? Devices located up to (before) the single open condition. Find job postings near you and 1-click apply! Failure to accept will result in a failed score and fees will be forfeited. Two detectors are more on each initiating device circuit. by Splextech1, All rights reserved. A secondary power supply is required to be able to operate a fire alarm system for ______ hours under non alarm conditions and then ________ minutes thereafter. hz. a. the value of the charging current at the first instant S1S_1S1 is moved to Position 111? (c) be installed only when approved by the AHJ. February 2020; July 2019; June 2019; October . How often are engine driven generators tested? Why is the name "suction cup" a bit of a misnomer? How often must household fire alarm system smoke detectors be tested by a qualified alarm tech? Level 2 >>http://firealarmscertified.com/nicet-fire-alarm-systems-level-2-study-guide/. The design engineer has specified the appliance to be protected from flying objects using a wire . Feel free to browse other questions here. Operating the alarm switch electrically or mechanically annually, and verifying receipt of the alarm signal at the fire alar control unit. 75 terms. Is the complex neutral or is it charged? {"cdnAssetsUrl":"","site_dot_caption":"Cram.com","premium_user":false,"premium_set":false,"payreferer":"clone_set","payreferer_set_title":"NICET Fire Alarm Level 1","payreferer_url":"\/flashcards\/copy\/nicet-fire-alarm-level-1-8463689","isGuest":true,"ga_id":"UA-272909-1","facebook":{"clientId":"363499237066029","version":"v12.0","language":"en_US"}}. According to NFPA 72 how often are VISDs to be tested to verify that there are no obstructions in the detectors field of view? According to, how many spot type heat detectors are required for a space that is 80 foot long and 55-foot wide with a smooth 10 foot ceiling? When are visual alarm notification devices required to be tested? A complete record of the tests and operations of each system is required to be kept until the next text, and then ____________. For the 5 years of testing and for 1 year thereafter. 375 ma (milliamps) can also be expressed as ___________. No trouble signal or gate operation would occur. One of the best ways to study for your NICET exam is through online courses provided by Fire Tech Productions. NICET Fire Alarm Systems Level 1 Exam Study Guide ? Brain damage can also occur. It's pretty simple, I was able to pass it on my first attempt. An email has been sent to you with your results. Click on the slide to start the timer and begin the test. How frequently are rate-compensated heat detectors to be tested? An Introduction to Fire Alarm Systems; NICET Fire Alarm Systems Levels 1 & 2 Study Guide; 2018 NICET Fire Alarm Systems Level 2 Study Guide; 2018 NICET Fire Alarm Systems Level 1 Study Guide; NICET Certification Fire Alarm System Pop Quiz Question-Concealed Duct Detector; Recent Comments. Quickly memorize the terms, phrases and much more. What does an inspection of a fire alarm system power supply do? C. not less than 4-1/2 feet, and not more than 5-1/2 feet This error message is only visible to WordPress admins, NICET Fire Alarm Systems Level 1 Exam Study Guide, NICET Fire Alarm Systems Level 2 Study Guide, The Value and Importance of NICET Fire Alarm Certification, http://firealarmscertified.com/fire-alarms-systems-nicet-level-1-exam-study-guide/, http://firealarmscertified.com/nicet-fire-alarm-systems-level-2-study-guide/, NICET Certification Fire Alarm System Pop Quiz Question, NICET Fire Alarm Systems Levels 1 & 2 Study Guide, 2018 NICET Fire Alarm Systems Level 2 Study Guide, 2018 NICET Fire Alarm Systems Level 1 Study Guide, NICET Certification Fire Alarm System Pop Quiz Question-Concealed Duct Detector. When testing a high/low air pressure switch, a ________ psi change shall cause the required signal. Who does NFPA 72 require you to notify? What are the colors and corresponding number codes of a resistor? Fire alarm systems that are not monitored for alarm supervisory and trouble signals shall have their lamps and LED's visually inspected at what frequency? Where detectors are installed but not operational during construction, they shall be __________________________________. ix5Eh^-T |R^640p^kFF}G(bI=z/&J*#wmeW-V;v Whiplash injuries during an automobile accident are caused by the inertia of the head. Starting October 1, 2018, the NICET Fire Alarm System exam content for Levels I will be updated to the following references: NFPA 70 2014, NFPA 72 2016, NFPA 101 2015, IBC 2015. What is the Maximum number of No. Welcome to the NICET Inspection & Testing of Fire Alarm Systems Sample Test! Select three of the following items which are symptoms of heat exhaustion. NICET will contact the applicant to arrange a mutually suitable accommodation. 176 terms. A factory Uses a motorized gate opener for access to there facility. After the final acceptance test, how is the owner given the software programing for his system? These courses are designed to help those preparing for the NICET Fire Alarm Systems Certification - Level I, II, III. How do you test a non restorable heat detector? Introducing Cram Folders! Transformers and other power sources for power-limited fire alarm circuits must be protected by an over-current device rated at not more that__________? Sample NICET Inspection & Testing of Water-Based Systems Practice Test. February 2020; July 2019; June 2019; October 2018; , learning the proper way to navigate the referencessuch as NFPA 72 (2013) and NEC or NFPA 70 (2011). You have already completed the quiz before. There are many functions that are served by the fire alarm system and it all may be a bit confusing to someone new to fire alarms, so I decided to create a visual guide to fire alarm basics. The process is not complete until you click the Confirm Reschedule button, see the notice: Your Appointment is Rescheduled and receive a confirmation email. What is the maximum allowable spacing for a hat detector which is listed for 50 foot spacing, when it is mounted on a smooth, flat, 23-foor high ceiling? How many heat detectors with a listed 30 foot spacing are required? What is the minimum voltage for power-limited fire alarm cables? I understand that NICET tests and test questions are owned and copyrighted by NICET and affirm that I will not share the content of any NICET examination with any other person. NICET Fire Alarm Systems Level I Pop Quiz #6 Answer. Have A NICET Day Electrical Contractor Magazine. What is the maximum number of NO. Happy studying! Each attempt of a DACT to send a test signal to the supervising station may take up to ________, Fire alarm system components shall be installed, tested , and maintained in accordance with ________. The best way to reschedule your exam is to login to your NICET account and click Schedule in the left side navigation then Schedule with Pearson VUE for the exam you want to reschedule. Then click the exam name to view the appointment then Reschedule on the right side of the screen. What shall be done when testing basic interfaces? Caution: Just like the original scheduling process there are several screens, agreements, and confirmations. In a few questions, you may be presented a picture and asked to click on the part of the picture that correctly answers the question. The ceiling is 10 feet high and level. Activated detectors between the control unit and that detector base should alarm. Are all supplemental circuits required to be monitored for integrity? Inspections, testing, or maintenance shall be permitted to be done by a person or organization other then the owner if___________. For more information about taking the Standard Model exam, please click here. False, Removal of the release control solenoid keeps the system from releasing when the detectors are tested. To answer this question, we use the index to locate our keyword: detectors, which points us to various types of detectors. The Fire Alarm Systems exam is delivered on a computer at Pearson Vue Testing Centers. Cram has partnered with the National Tutoring Association, Antiquated Simplex Firearm System Case Study, The Importance Of The UK Building Regulations, Compare And Contrast Freudy And Paul Valentine's. Fire. Manual fire alarm boxes shall be located within ________ of the exit doorway opening at each exit on each floor. the same building.b. February 2020; July 2019; June 2019; October . Please contact PearsonVUE. An 180 foot long corridor is 10 feet wide, with a smooth 10 foot ceiling, interrupted by 4-inch beams spaced every 10 feet. Nicet Level 3 Tips NICET Certification training and. NICET Level 1 ITM of Water Based Systems. Eliminate Battery back-up Trouble on FACP, Smoke Detector Placement for Door Release. You will receive your score at the conclusion of your test session. The circuit disconnect means (breaker) for a fire alarm system to the power source shall _____________. Study Flashcards On NICET Fire Alarm Level 1 at Cram.com. 2018 NICET Fire Alarm Systems Level 1 Study Guide; NICET Certification Fire Alarm System Pop Quiz Question-Concealed Duct Detector; Recent Comments. How long does NFPA 72 state out-of-service (impairment) records are to be kept? whom is supposed to be doing the T&I of the fire alarm system. You may also call Pearson VUE at 1-866-880-0048 to reschedule. What is the equivalent resistance? A secondary power supply for protected premises shall automatically provide power within _______ seconds of the primary power fails. Successful candidates must pass an exam or exams, complete a work history description that documents and meets specific industry related experience, successfully perform key role specific activities, and obtain a personal recommendations (Levels III and IV). Audible notification appliances intended for operation in public mode shall have a sound level at least _____________ above the average ambient level or ___________ above the maximum sound level. What type of cable is required for this if the cable will not be installed in a metal raceway or fireproof shaft? R Quiz 1: Basic Fire Alarm. During the acceptance test and annually thereafter. If charged, give the charge. Michael_Coomer2 Teacher. True or False, A according to NFPA 72 a qualified fire alarm service tech needs to Understand & apply requirements to properly design a fire alarm system? The instructor. This course covers certification procedures and requirements, testing strategies, and NFPA code books. NICET understands that learning the applicablecodes and how to navigate these references will get you a lot further than forcing you to memorize all of the material. Congratulations on passing Level 1. The temperature of the air surrounding a heat detector when its activated, is usually considerably higher then raited temperature of the detector. guards, covers, or lenses are employed, they shall ____________________. Who is responsible for maintaining a record of impairment or out of service event? have a red marking and be identified as "FIRE ALARM". On the inspection record you must now________. Find out how you can intelligently organize your Flashcards. However, her head is free to move until the neck restrains it, causing damage to the neck. Monitoring for integrity shall not be required for the interconnection between listed equipment within _____.a. Title Page - Edit and print this page with the information about the reference, according to the standard. (d) all of the above. Basic test equipment questions. The fire alarm panel uses an on-board relay to open the gate upon alarm, What operation or signal is required of this circuit should an open occur? If you would like more NICET certification fire alarm exam questions, check out our study guides: Level 1 >>http://firealarmscertified.com/fire-alarms-systems-nicet-level-1-exam-study-guide/ Level II Exam: 76 questions, 110 min. Jobs . Rescheduling you NICET exam has never been easier and in most cases does not incur any additional fees. Explain how wind might affect living things in an ecosystem. The time delay between the activation of an initiating device and the automatic activation of emergency control functions, shall not exceed __________. (broken wire to gate opener)? The NDA that will be displayed is: You must accept the Non-Disclosure Agreement (NDA) below in order to take this exam. These little practices can cut down on your time thus reducing anxiety as well as giving you time to circle back at the end of your NICET exam to answer any questions you were unsure on. . 70E, Confined space, fall protection, ladders, fire extinguishers. Applicants are presented with the option to select online administration through OnVue during the scheduling step. (a) be listed for use with the appliance. All supervising station alarm systems transmission equipment shall report initiating device activation within how long? Secondary power supplies for an emergency voice/alarm communications fire alarm system shall be capable of operating for a minimum of _________ of standby followed by __________ of alarm. (d) be at least twice the size of the installed appliance. Please sign in to share these flashcards. W U [Content_Types].xml ( Io0z)lK@DjU#)>I7^,&9DTirnXu&n;%M|X],6_]d7.>snr0iE!)+=noMol#s*o[}q,i7r'V}>ne7:4{\YK2,fU}=+y^!%ZUvDydjI|U?#54x[C*'Kqq-]4Gs/ STWp\AW0/OE"sddx42OGOGgF]]]]]]]===_tttttttttt ccccc@CCCCCCWh1111111111&ccccccccccBB78vp@?C!!h w;]p 'Ifpqsuwy{}00FBxh #al400NFJxi3 #a400FR@.Qg'~J&('~JZR^!yrF~Yj[{Z_^U;Rrq*q*q*q*q*q*q*q*~6"+x-5isuj;nOq`rt/ PK ! Which of the following shall be done when conducting tests in lead-acid type batteries. Level I the same zo. Who should be informed first when a tech is planning to perform an inspection or testing of a commercial fire alarm system? In a power limited fire alarm system the size of conductors in a multi colors cable shall not be smaller than __________AWG, single conductors shall not be smaller than _____________.