NFPA 70 – NEC:
110.16 Arc-Flash Hazard Warning : Electrical equipment, such as switchboards, switchgear, panelboards, industrial control panels, meter socket enclosures, and motor control centers, that are in other than dwelling units, and are likely to require examination, adjustment, servicing, or maintenance while energized, shall be field or factory marked to warn qualified persons of potential electric arc flash hazards. The marking shall meet the requirements in 110.21(B) and shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing, or maintenance of the equipment.

NPFA 70E:
130.5 Arc Flash Risk Assessment: An arc flash risk assessment shall be performed and shall:
(1) Determine if an arc flash hazard exists. If an arc flash hazard exists, the risk assessment shall determine:
a. Appropriate safety-related work practices
b. The arc flash boundary
c. The PPE to be used within the arc flash boundary
(2) Be updated when a major modification or renovation takes place. It shall be reviewed periodically, at intervals not to exceed 5 years, to account for changes in the electrical distribution system that could affect the results of the arc flash risk assessment.
(3) Take into consideration the design of the overcurrent protective device and its opening time, including its condition of maintenance.

OSHA requirement:
OSHA 1910.335 (a)(1)(i):
Employees working in areas where there are potential electrical hazards shall be provided with, and shall use, electrical protective equipment that is appropriate for the specific parts of the body to be protected and for the work to be performed.
OSHA 1926.960: addresses protecting employees from flames and electric arcs. This paragraph requires employers to: (1) Assess the workplace for flame and electric-arc hazards (paragraph (g)(1)); (2) estimate the available heat energy from electric arcs to which employees would be exposed (paragraph (g)(2)); (3) ensure that employees wear clothing that will not melt, or ignite and continue to burn, when exposed to flames or the estimated heat energy (paragraph (g)(3)); and (4) ensure that employees wear flame-resistant clothing and protective clothing and other protective equipment that has an arc rating greater than or equal to the available heat energy under certain conditions.
OSHA Requires Arc Flash Calculation be done by a standard that has been adopted by a nationally recognized standards producing organization which is NPFA 70 & 70E that address Arc Flash calculation requirement.