API Publ 2026:1998 pdf download
API Publ 2026:1998 pdf download.Safe Access/Egress Involving Floating Roofs of Storage Tanks in Petroleum Service.
3.4 entry: Any work activity involving entry onto a floating roof. Entry occurs as soon as any part of an entrant’s body goes past the top of the tank preparatory to descent upon the floating roof.
a. Atte’ndant is a trained and qualified person stationed outside a permit-required confined space to monitor the entrants and perform attendant duties in accordance with the facility’s Permit Space Program.
b. Entrant is a person who is trained, qualified, and authorized to enter permi-required confined spaces.
c. Entry supervisor is a person who by training and experience is qualified and authorized to allow entry for work in permit-required and non-permit-required confined spaces and who is familiar with the tasks to he performed, the potential hazards that may he encountered in the confined space. the safety and health requirements for work in the confined space and the facility’s Permit Space Program. Designated Entry Supervisors are responsible to determine that acceptable permit-required confined space entry conditions are present and met; to authorize entry into permit and non—permit—required confined spaces; to assign or act as required testers, entrants, attendants and rescuers; to oversee entry operations; and to terminate entry as required.
d. Tester is a person who is trained and qualified to operate, calibrate and adjust instruments, and conduct appropriate atmospheric testing. When descending upon floating roofs to conduct testing, the tester then becomes an entrant. A tester or an entrant can also be an entry supervisor
3.5 exposure limit: The maximum airborne concentration limits for toxic substances to which workers may he safely exposed for a prescribed time without protection (i.e., respiratory protection). Exposure limits are usually expressed in parts per million or milligrams per cubic meter, averaged for a prescribed time, e.g., 15 minutes, 8 hours. They may also he expressed as ceiling limits, which should not he exceeded. Material safety data sheets (MSDSs) available from employers, manufacturers or suppliers of the material should identify recommended exposure limits of the product stored in the tank.
a. Permissible Eposure Limits (PELs) are exposure limits established in the Occupational Safety and Health Administration, U. S. Department of Labor regulations and are those found in the most current editions of OSHA 29 CFR 19 10.1000 and chemical specific standards.
b. Hazardous atmo.sphere is an atmosphere which may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue, injury, or acute illness from (1) flammable gas, vapor or mist in excess of 10% LFL, (2) airborne combustible dust at a concentration that meets or exceeds its LFL, (3) atmospheric oxygen concentration below 19.5% or above 23.5%, (4) atmospheric concentration of any substance in excess of its permissible exposure limit, and (5) any other atmospheric condition which is immediately dangerous to life or health.
Note: OSHA Standards. MSDSS, facility documents and other published information may be used to provide guidance for acceptable atmospheric exposure limits for vapors and toxic contaminants.
3.6 flammable vapor limit: The concentration of vapor in normal air which will ignite upon contact with a source of ignition.
Note: Flammable vapor limits will be extended in oxygen-enriched atmospheres. The following definitions for LFL and UFL are based on definitions of flammable vapor limits given in NFPA 325M.
a. Lower Flammable Limit (LFL) is the minimum concentration of a vapor in air below which propagation of flame does not occur on contact with an ignition source and is generally considered to he “too lean to burn.” LFL is usually expressed as a volume percentage of the vapor in air.
b. Upper Flammable Limit (UFL) is the maximum concentration of a vapor in air above which propagation of (lame does not occur upon contact with an ignition source and is generally considered to be “too rich to bum.” UFL is usually expressed as a volume percentage of the vapor in air.
