The post AutoQuiz: How to Assess the Hazard/Risk Category for an Industrial Electrical Panel first appeared on the ISA Interchange blog site.
Today’s automation industry quiz question comes from the ISA Certified Automation Professional certification program. ISA CAP certification provides a non-biased, third-party, objective assessment and confirmation of an automation professional’s skills. The CAP exam is focused on direction, definition, design, development/application, deployment, documentation, and support of systems, software, and equipment used in control systems, manufacturing information systems, systems integration, and operational consulting. Click this link for more information about the CAP program.
A control circuit within Field Control Panel #1 (FCP-1) in your facility is malfunctioning, and you must initiate a work order to have a technician troubleshoot the circuit. FCP-1 contains a PLC, terminal blocks, circuit breakers and fuses, and various other control equipment, of which none exceeds 120vac. The technician will be working on energized electrical conductors and circuit parts and performing voltage testing on the live circuits. On the work order, you will be required to state under which NFPA 70E-2009 Standard for Electrical Safety in the Workplace Hazard/Risk Category this work activity falls.
Per NFPA 70E-2009 Standard for Electrical Safety in the Workplace, what Hazard/Risk Category should be defined for the above task?
a) Hazard/Risk Category 0
b) Hazard/Risk Category 1
c) Hazard/Risk Category 2*
d) Hazard/Risk Category 4
e) none of the above
Answer A, Hazard/Risk Category 0, is incorrect as it typically relates to non-contacting work on various voltage ranges.
Answer C, Hazard/Risk Category 2*, is incorrect as it relates to work on equipment with voltage present that is greater than 240V.
Answer D, Hazard/Risk Category 4, is incorrect as it relates to work on equipment with voltage present that is 600V or greater.
The correct answer is B, Hazard/Risk Category 1. Per NFPA 70E-2009 Table 130.7(C)(9), work on energized electrical conductors and circuit parts, including voltage testing on panelboards, or other equipment rated 240V and below would be classified as Hazard/Risk Category 1.
Reference: NFPA 70E-2009 Standard for Electrical Safety in the Workplace
Source: ISA News