API RP 2026-2017 pdf download.Safe Access/Egress Involving Floating Roofs of Storage Tanks in Petroleum Service.
22.214.171.124 non-permit-required confined space A confined space (a space that meets all three of the confined space requirements) that has been checked, inspected, had its atmosphere monitored, and does not have (or does not have the potential to have) any of the characteristics required to be classified as a permit-required confined space. 126.96.36.199 permit-required confined space A tank or space that meets the confined space requirements and also has one or more of the following characteristics: a) contains or has the potential to contain a hazardous atmosphere, b) contains a material with the potential to engulf an entrant, c) has an internal configuration such that an entrant could become trapped or asphyxiated, d) contains any other recognized serious safety or health hazard(s), or e) has a floating roof not properly prepared and secured in accordance with API 2015. 188.8.131.52 permit-required confined space program The employer’s overall program for controlling and regulating entry into permit-required confined spaces and, where appropriate, protecting employees from permit space hazards. 3.1.4 entry The action by which an entrant passes through an opening into a confined space. Entry includes ensuing work activities in both permit-required confined spaces and non-permit-confined spaces and is considered to have occurred as soon as a part of the entrant’s body breaks the plane of an opening into the space. 3.1.5 flammable vapor limit The concentration of vapor in normal air that will ignite upon contact with a source of ignition. 184.108.40.206 lower explosive (flammable) limit LEL The minimum concentration (expressed as a volume percentage) of a vapor-in-air below which propagation of flame does not occur on contact with an ignition source; generally considered to be “too lean to burn.”
3.1.7 floating roof, internal A floating roof that is designed and constructed in accordance with the provisions of API 650, Annex H. An internal floating roof is designed to be used only on a tank with a fixed roof. 3.1.8 floating roof tank Any aboveground vertical atmospheric storage vessel that is equipped with either an external or internal floating roof. 220.127.116.11 floating roof A moveable cover that floats on top of the product in a floating-roof tank. 18.104.22.168 in-service floating roof tank A tank that contains a quantity of petroleum product that could cause a flammable, oxygen-deficient, or toxic atmosphere above the floating roof. 3.1.9 hazardous atmosphere An atmosphere that has the potential to expose entrants to the risk of death, incapacitation, impairment of ability to self-rescue (escape unaided from a confined space), injury, or acute illness from one or more of the following causes. a) Flammable gas, vapor, or mist in excess of 10 % lower explosive (flammable) limit (LEL). b) Airborne combustible dust at a concentration that meets or exceeds 80 % of its LEL. The LEL may be approximated as a condition in which the dust obscures vision at a distance of 5 ft (1.5 m) or less. c) Atmospheric oxygen concentration below 19.5 % or above 23.5 %. d) Atmospheric concentration of any substance for which a dose or permissible exposure limit (PEL) is published in applicable government regulations, safety data sheets (SDSs), standards, or other publications or internal documents and that could result in employee exposure in excess of the substance’s dose or PEL. e) Any other atmospheric condition immediately dangerous to life or health (IDLH). 3.1.10 hot work Any work that has the potential to produce enough thermal energy to provide an ignition source in an area where a potential exists for a flammable gas or vapor-in-air atmosphere in the explosive (flammable) range to occur.