§ 152.06 DEFINITIONS.
   For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
   ATTENDANT. A person who is assigned as standby to monitor confined space process or operation and provide support or react as required.
   BLINDING/BLANKING. Inserting a solid barrier across the open end of a pipe leading into or out of the confined space, and securing the barrier in such a way to prevent leakage of material into the confined space.
   CONFINED SPACE. An enclosed area that has the following characteristics:
      (1)   Its primary function is something other than the human occupancy;
      (2)   Has restricted entry and exit; and
      (3)   May contain potential or known hazards.
   DOUBLE BLOCK AND BLEED. A method used to isolate a confined space from a line, duct or pipe by physically dosing two-in-line valves or a piping system, and opening a vented-to-atmosphere valve between them.
   ENTRY. Ingress by persons into confined space which occurs upon breaking the plane of the confined space portal with his or her face; and all periods of time in which the confined space is occupied.
   HAZARD EVALUATION. A process to assess the severity of known, real or potential hazards or all three, at or in the confined space.
   HAZARDOUS CHEMICAL. As defined by OSHA, a chemical for which there is statistically significant evidence based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur in exposed employees.
   HOT WORK. Work within a confined space that produces arcs, sparks, flames, heat or other sources of ignition.
   ISOLATION. A process of physically interrupting, or disconnecting, or both, pipes, lines and energy sources from the confined space.
   LEL/LFL and UEL/UFL. Acronyms for lower explosive limit/lower flammable limit and upper explosive limit/upper flammable limit.
   LOCKOUT/TAG OUT. The placement of a lock/tag on the energy isolating device in accordance with an established procedure, indicating that the energy isolating device shall not be operated until removal of the lock/tag in accordance with an established procedure.
   OXYGEN DEFICIENT ATMOSPHERE. An atmosphere containing less than 19.5% oxygen by volume.
   OXYGEN ENRICHED ATMOSPHERE. An atmosphere containing more than 23.5% oxygen by volume.
   PEL. An acronym for permissible exposure limit which is the allowable air contaminant level established by the U.S. Department of Labor, Occupational Safety and Health Administration
   QUALIFIED PERSON. A person who by reason of training, education and experience is knowledgeable in the operation to be performed and is competent to judge the hazards involved.
   SHALL. Denotes a mandatory requirement.
   SHOULD. A recommendation that is sound safety and health practice, it does not denote a mandatory requirement.
   TLV. An acronym for threshold limit value.
   TOXIC ATMOSPHERE. An atmosphere containing a concentration of a substance above the published or otherwise known safe levels.
(Ord. passed - -)