ANSI ASSP A10.16-2009 pdf download.Safety Requirements for Tunnels, Shafts and Caissons
3.14.5 Material Lock. A lock designed for and primarily used for the passage of materials and equipment.
3.14.6 Medical Lock. A special lock in which workers suffering from decom- pression illness may be placed for medical attention and treatment. The medical lock may also be used for pre-employment physical examinations to determine the adaptability of prospective employee(s) to changes in pressure.
3.14.7 Working Man Lock. A personnel lock, combination lock or long lock that is normally used by personnel for entering or leaving the working chamber. Synonymous with Working Person Lock. 3.15 Pressure. A force exerted over a unit area, usually indicated in pounds per square inch (psi).
3.15.1 Atmospheric Pressure. The normal air pressure of free atmospheric air at sea level. In this standard, atmospheric pressure is assumed to be 1 4.7 psi. Atmospheric pressure is always 0 psig (1 01 .4 kPa) (see Gauge Pressure).
3.15.5 Working Pressure. The pressure established at any time by the air master, or their duly authorized alternate, to be the required air pressure in the working chamber.
3.16 Primary Lining. A support, usually of timber or steel, or both, that is placed to retain soil or rock loads immediately after excavation and is usually covered afterward by a permanent lining of masonry or concrete. Synonymous with Primary Liner.
3.17 Qualified Person. A person who, by possession of a recognized degree, certificate or professional standing, or by extensive knowledge, training and exper- ience, has demonstrated their ability to solve or resolve problems relating to the subject matter of this standard.
3.18 Rapid Flooding. A hazardous condition resulting in the rapid rise of water in the working chamber when the air pressure is lowered, whether by design or otherwise.
3.19 Safety Screen. An airtight and watertight diaphragm placed across the upper part of a compressed-air tunnel, between the face and the bulkhead, in order to prevent flooding the crown of the tunnel between the screen itself and the bulkhead, thus providing a safe refuge and means of exit from a flooding or flooded tunnel.
4.4 Existing Utilities. Prior to the commencement of work, the employer shall identify and ascertain the location of each underground utility and any other utility adjacent to the work. Utility companies shall be contacted and advised of proposed work prior to the start of actual excavation. When it has been verified that locations have been marked, the work may start. Any utilities creating a hazard to employees or the public shall be properly safeguarded or removed.
4.5.3 No person shall be permitted to carry or use intoxicating liquor or controlled substances in a tunnel, shaft or caisson. Any person known to be under the influence of intoxicating liquor or controlled sub- stances shall not be permitted to enter such premises. Any worker using prescription medicines shall obtain a work clearance from the physician prior to working underground.
4.5.4 Employees working alone and out of range of natural unassisted voice communication shall be provided with an effective means of communicating and obtaining assistance in an emergency. A system for checking in no less than once each hour shall be provided, and failure to check in will initiate an immediate investigation.
4.5.5 All machinery, equipment, appli- ances, materials, structures and work places shall be maintained in a safe condition, free of all recognized hazards at all times, in accordance with the equipment manufacturers’ instructions, and shall be periodically inspected for unsafe conditions or defects by a competent person(s) designated by the employer. Every employee shall be directed to advise their supervisor immediately of any observed defects or unsafe conditions.ANSI ASSP A10.16-2009 pdf download
