API MPMS 17.11 2009 pdf free download

API MPMS 17.11 2009 pdf free download.Measurement and sampling of cargoes on board tank vessels using closed and restricted equipment.
3.12 stand pipe A vertical section of pipe extending from the top of a marine vessel tank through which measurements and samples of tank contents can be obtained. NOTE Stand pipes are frequently fitted with vapor control valves to allow closed or restricted operation. The pipe should extend to the floor of the tank with the internal part (also called “stilling well” or “still pipe”) slotted to allow free flow of tank contents while providing guidance for gauging and sampling equipment. 3.13 static accumulator oils Oils having a conductivity of less than 50 pS/m; these oils relax (dissipate charge) slowly. 3.14 UTI Ullage, temperature and interface 3.15 vapor control valve VCV Valve fitted on a stand pipe, expansion trunk or the deck that permits use of the portable hand-held gauging instruments while restricting the release of vapors into the atmosphere. 3.16 vapor pressure RVP, TVP Reid vapor pressure (RVP): The vapor pressure of a liquid at 100 °F (37.8 °C, 311 °K) as determined by ASTM D323. True vapor pressure (TVP): The pressure at which the fluid is in equilibrium between its liquid and gas state. 3.17 volatile organic compounds VOCs Organic chemicals that have a high vapor pressure and easily form vapors at normal temperature and pressure. 3.18 washing, crude oil COW Use of a high pressure stream of the crude oil cargo to dislodge or dissolve clingage and sediment from the bulkheads, bottom, and internal tank structures of a vessel during the discharge operation.
4.2 Static Electricity Hazards If the tank is in a non-inert condition, specific precautions will be required with regard to safe measurement and sampling procedures when handling static accumulator oils. These are generally as follows. During loading, and for 30 minutes after the completion of loading, metallic equipment for dipping (gauging), ullaging or sampling shall not be introduced into or remain in the tank. Examples of equipment include manual steel ullage tapes, portable gauging devices mounted on deck stand pipes, metal sampling apparatus and metal sounding rods. Non-conducting equipment with no metal parts may, in general, be used at any time. However, ropes or tapes used to lower equipment into tanks shall not be made from synthetic materials. After the 30-minute waiting period, metallic equipment may also be used for dipping (gauging), ullaging and sampling but it is essential that it is effectively bonded and securely earthed to the structure of the ship before it is introduced into the tank and that it remains earthed until after it has been removed. Operations carried out through stand pipes are permissible at any time because it is not possible for any significant charge to accumulate on the surface of the liquid within a correctly designed and installed stand pipe. A stand pipe should extend the full depth of the tank and be effectively bonded and earthed to the tank structure. 4.3 Health Hazards Petroleum vapor dilutes oxygen in the air and may also be toxic. Hydrogen sulfide vapors are particularly hazardous. Petroleum vapors with relatively low concentrations of hydrogen sulfide may cause unconsciousness or death. During and after the opening of a VCV, personnel should position themselves to avoid any gas which may be released. Harmful vapors or oxygen deficiency cannot always be detected by smell, visual inspection, or judgment. Appropriate precautions should be used for the protection against toxic vapors or oxygen deficiency.
Procedures should be developed to provide for the following: a) exposure monitoring, b) need for personal protective equipment, and c) emergency rescue precautions. When necessary, suitable fresh air breathing equipment should be worn prior to entering the gauge site and during the gauging and sampling procedure. This discussion on safety issues is not exhaustive and the appropriate API or Energy Institute publications, together with the International Safety Guide for Oil Tankers and Terminals (ISGOTT), Safety of Life at Sea (SOLAS), and Oil Companies International Marine Forum (OCIMF) publications should be consulted for applicable safety precautions. 5 Types of Equipment 5.1 General Ship-owner, charterer or terminal safety or environmental regulations may restrict tank gauging and sampling operations which result in the release of inert gas, hydrocarbons or other volatile organic compounds (VOCs) into the atmosphere. In these circumstances, traditional open gauging and sampling procedures will not be permitted.