What Does High Voltage Mean?
High voltage is a term that usually refers to any level of voltage that is high enough to inflict harm to living organisms, particularly humans.
The term also refers to voltage above a specific threshold, which depends on the occupational context that it is used in.
Safeopedia Explains High Voltage
In the context of building wiring and the general use of an electrical apparatus, the International Electrotechnical Commission defines high voltage as more than 1,000 volts (V) of alternating current (AC) and above 1,500 V of direct current (DC). This is also the definition used by the UK Health and Safety Executive.
OSHA does not have a consistent definition for high voltage—OSHA standard 1910.304(g)(9) for grounding fixed equipment refers to fixed equipment as anything higher than 1,000 volts, whereas other OSHA standards such as 1910.303(h)(5)(ii) refer to high voltage as being above 600 volts.
The definition of high voltage varies because the amount of voltage that might be considered dangerous to a given individual is different depending on the individual’s level of electrical expertise. "High voltage" in an everyday work setting is geared toward warning unqualified persons that an item poses enough electricity to harm or kill them. For electrical workers, "high voltage" refers to an elevated risk threshold. In this context, the term tells workers valuable information about the nature of the system they are working on to allow them to make informed decisions about working safely.
Equipment and systems that feature high-voltage components are subject to a variety of individual safety guidelines that regulate their accessibility, use, and design. For instance, OSHA requires high-voltage equipment to be grounded and surrounded with sufficient open space for electrical workers to operate safety.
Unprotected high-voltage equipment must also be separated from work spaces in which unqualified persons are present, labeled with warning signs, and protected by a locked barrier or security person. Work on high-voltage equipment may be further regulated by safety standards such as the use of personal protective equipment and mandatory grounding or de-energizing procedures.