Marine and offshore industry recommends to use oil mist detectors. They recommend oil mist detectors for safety of engine and crew onboard. While engine is running oil mist detectors checking continuously any vapor or oil mist in the crankcase of engine. Atmospheric oil mist detectors is also very important to install in open space or in framo pump room, oil purifier room, high pressure pump room, engine room. Crankcase oil mist detectors for monitoring of oil mist in engine crankcase. The G26 and VISION IIIA Ambient Oil Mist Detector is used to detect oil mist in open spaces such as pump rooms, engine rooms, and other facilities. The G26 and VISION IIIA has the several decisive advantages compared to the single point extractive sampling system. Each detector can cover a much larger area. The scanning distance of a detector is from 1 to 15 meters. The oil mist detectors has been developed for use in enclosed oil rig well head areas, generator rooms and turbine enclosures. The oil mist detector uses photoelectric cells to measure small increases in oil mist density. A motor driven fan continuously draws samples of crankcase oil mist through a measuring tube. The level model tests each crankcase in turn against a reference tube sealed with clean air Type Testing Procedure for Crankcase Oil Mist Detection and Alarm Equipment If a forced extraction of the oil mist atmosphere from the crankcase is provided (for mist detection purposes for instance), the vacuum in the crankcase is not to exceed 2.5 x 10–4 N/mm2 (2.5 m bar). Oil mist detection arrangements (or engine bearing temperature monitors or equivalent devices) are required: for alarm and slow down purposes for low speed diesel engines of 2250 kW and above or having cylinders of more than 300 mm bore for alarm and automatic shutoff purposes for medium and high-speed diesel engines of 2250 kW and above or having cylinders of more than 300 mm bore Oil mist detection arrangements are to be of a type approved by classification societies and tested in accordance with UR M67 and comply with UR M10.9 to UR M10.20. Engine bearing temperature monitors or equivalent devices used as safety devices have to be of a type approved by classification societies for such purposes. Note: For equivalent devices for high speed engines, refer to UI SC 133. The oil mist detection system and arrangements are to be installed in accordance with the engine designer’s and oil mist manufacturer’s instructions/recommendations. The following particulars are to be included in the instructions: Schematic layout of engine oil mist detection and alarm system showing location of engine crankcase sample points and piping or cable arrangements together with pipe dimensions to detector. Evidence of study to justify the selected location of sample points and sample extraction rate (if applicable) in consideration of the crankcase arrangements and geometry and the predicted crankcase atmosphere where oil mist can accumulate. The manufacturer’s maintenance and test manual. Information relating to type or in-service testing of the engine with engine protection system test arrangements having approved types of oil mist detection equipment. A copy of the oil mist detection equipment maintenance and test manual required by UR M10.9 is to be provided on board ship. Oil mist detection and alarm information is to be capable of being read from a safe location away from the engine. Each engine is to be provided with its own independent oil mist detection arrangement and a dedicated alarm. Oil mist detection and alarm systems are to be capable of being tested on the test bed and board under engine at standstill and engine running at normal operating conditions in accordance with test procedures that are acceptable to the classification society. Alarms and shutdowns for the oil mist detection system are to be in accordance with UR M35 and UR M36 and the system arrangements are to comply with UR M29 and UR The oil mist detection arrangements are to provide an alarm indication in the event of a foreseeable functional failure in the equipment and installation arrangements. The oil mist detection system is to provide an indication that any lenses fitted in the equipment and used in determination of the oil mist level have been partially obscured to a degree that will affect the reliability of the information and alarm indication. Where oil mist detection equipment includes the use of programmable electronic systems, the arrangements are to be in accordance with individual classification society requirements for such systems. Plans of showing details and arrangements of oil mist detection and alarm arrangements are to be submitted for approval in accordance with UR M44 under item 28. The equipment together with detectors is to be tested when installed on the test bed and on-board ship to demonstrate that the detection and alarm system functionally operates. The testing arrangements are to be to the satisfaction of the classification society. Where sequential oil mist detection arrangements are provided the sampling frequency and time is to be as short as reasonably practicable. Where alternative methods are provided for the prevention of the build-up of oil mist that may lead to a potentially explosive condition within the crankcase details are to be submitted for consideration of individual classification societies. The following information is to be included in the details to be submitted for consideration: Engine particulars – type, power, speed, stroke, bore and crankcase volume. Details of arrangements prevent the buildup of potentially explosive conditions within the crankcase, e.g., bearing temperature monitoring, oil splash temperature, crankcase pressure monitoring, recirculation arrangements. Evidence to demonstrate that the arrangements are effective in preventing the buildup of potentially explosive conditions together with details of in-service experience. Operating instructions and the maintenance and test instructions. Where it is proposed to use the introduction of inert gas into the crankcase to minimize a potential crankcase explosion, details of the arrangements are to be submitted to the classification society for consideration. When required by UR M10.8 or by SOLAS Reg. II-1/47.2. One oil mist detector for each engine having two independent outputs for initiating the alarm and shut-down would satisfy the requirement for independence between alarm and shut-down system. If a cross-head type engine is used as DFD, the crankcase is to be protected by oil mist detector or bearing temperature detector. Protection for piston underside space of cross-head type engine. In addition to the causes specified in 16.3.7 of IGC Code, the master gas valve is to be closed in case of any of the following: Oil mist detector or bearing temperature detector detects abnormality. Any kind of gas fuel leakage is detected. Abnormality specified in Abnormality specified in Type Testing Procedure for Crankcase Oil Mist Detection and Alarm Equipment. To specify the tests required to demonstrate that crankcase oil mist detection and alarm equipment intended to be fitted to diesel engines satisfy classification society requirements. Note: This test procedure is also applicable to oil mist detection and alarm equipment intended for gear cases. Recognized Standards. IACS Unified Requirement E10 Type Test Specification. Purpose The purpose of type testing crankcase oil mist detection and alarm equipment is seven-fold: To verify the functionality of the system. To verify the effectiveness of the oil mist detectors. To verify the accuracy of oil mist detectors. To verify the alarm set points. To verify time delays between oil mist leaving the source and alarm activation. To verify functional failure detection. To verify the influence of optical obscuration on detection. Note: Engines are to be fitted with crankcase oil mist detection and alarm equipment complying with this UR when: an application for certification of an engine is dated on/after 1 January 2007; or installed in new ships for which the date of contract for construction is on or after 1 January 2007. The requirements of 6.7 and 6.8 are to be uniformly implemented by IACS Societies from 1 January 2008. The “contracted for construction” date means the date on which the contract to build the vessel is signed between the prospective owner and the shipbuilder. For further details. regarding the date of “contract for construction”, refer to IACS Procedural Requirement (PR) No. 29. Test facilities Test houses carrying out type testing of crankcase oil mist detection and alarm equipment are to satisfy the following criteria: A full range of facilities for carrying out the environmental and functionality tests required by this procedure shall be available and be acceptable to the classification societies. The test house that verifies the functionality of the equipment is to be equipped so that it can control, measure and record oil mist concentration levels in terms of mg/l to an accuracy of ± 10% in accordance with this procedure. Functional tests All tests to verify the functionality of crankcase oil mist detection and alarm equipment are to be carried out in accordance with with an oil mist concentration in air, known in terms of mg/l to an accuracy of ±10%. The concentration of oil mist in the test chamber is to be measured in the top and bottom of the chamber and these concentrations are not to differ by more than 10%. See also 8.1.1.1. The oil mist monitoring arrangements are to be capable of detecting oil mist in air concentrations of between 0 and 10% of the lower explosive limit (LEL) or between 0 and a percentage corresponding to a level not less than twice the maximum oil mist concentration alarm set point. Note: The LEL corresponds to an oil mist concentration of approximately 50mg/l (~4.1% weight of oil in air mixture). The alarm set point for oil mist concentration in air is to provide an alarm at a maximum level corresponding to not more than 5% of the LEL or approximately 2.5mg/l. Where alarm set points can be altered, the means of adjustment and indication of set points are to be verified against the equipment manufacturer’s instructions. Where oil mist is drawn into a detector via piping arrangements, the time delay between the sample leaving the crankcase and operation of the alarm is to be determined for the longest and shortest lengths of pipes recommended by the manufacturer. The pipe arrangements are to be in accordance with the manufacturer’s instructions/recommendations. Detector equipment that is in contact with the crankcase atmosphere and may be exposed to oil splash and spray from engine lubricating oil is to be demonstrated as being such, that openings do not occlude or become blocked under continuous oil splash and spray conditions. Testing is to be in accordance with arrangements proposed by the manufacturer and agreed by the classification society. Detector equipment may be exposed to water vapor from the crankcase atmosphere which may affect the sensitivity of the equipment and it is to be demonstrated that exposure to such conditions will not affect the functional operation of the detector equipment. Where exposure to water vapour and/or water condensation has been identified as a possible source of equipment malfunctioning, testing is to demonstrate that any mitigating arrangements such as heating are effective. Testing is to be in accordance with arrangements proposed by the manufacturer and agreed by the classification society. Note: This testing is in addition to that required by 5.1.2(e) and is concerned with the effects of condensation caused by the detection equipment being at a lower temperature than the crankcase atmosphere. Detectors and alarm equipment to be tested. The detectors and alarm equipment selected for the type testing are to be selected from the manufacturer’s normal production line by the classification society witnessing the tests. Two detectors are to be tested. One is to be tested in clean condition and the other in a condition representing the maximum level of lens obscuration specified by the manufacturer. Method The following requirements are to be satisfied at type testing: Oil mist generation is to satisfy Oil mist is to be generated with suitable equipment using an SAE 80 monograde mineral oil or equivalent and supplied to a test chamber having a volume of not less than 1m3. The oil mist produced is to have a maximum droplet size of 5 µm. Note: The oil droplet size is to be checked using the sedimentation method. The oil mist concentrations used are to be ascertained by the gravimetric deterministic method or equivalent. Note: For this test, the gravimetric deterministic method is a process where the difference in weight of a 0.8 µm pore size membrane filter is ascertained from weighing the filter before and after drawing 1 liter of oil mist through the filter from the oil mist test chamber. The oil mist chamber is to be fitted with a recirculating fan. Samples of oil mist are to be taken at regular intervals and the results plotted against the oil mist detector output. The oil mist detector is to be located adjacent to where the oil mist samples are drawn off. The results of a gravimetric analysis are considered invalid and are to be rejected if the resultant calibration curve has an increasing gradient with respect to the oil mist detection reading. This situation occurs when insufficient time has been allowed for the oil mist to become homogeneous. Single results that are more than 10% below the calibration curve are to be rejected. This situation occurs when the integrity of the filter unit has been compromised and not all of the oil is collected on the filter paper. The filters require to be weighed to a precision of 0.1mg and the volume of air/oil mist sampled to 10ml. The testing is to be witnessed by authorised personnel from classification societies where type testing approval is required by a classification society. Oil mist detection equipment is to be tested in the orientation (vertical, horizontal or inclined) in which it is intended to be installed on an engine or gear case as specified by the equipment manufacturer. Type testing is to be carried out for each type of oil mist detection and alarm equipment for which a manufacturer seeks classification approval. Where sensitivity levels can be adjusted, testing is to be carried out at the extreme and mid-point level settings. Assessment Assessment of oil mist detection equipment after testing is to address the following: The equipment to be tested is to have evidence of design appraisal/approval by the classification society witnessing tests. Details of the detection equipment to be tested are to be recorded such as name of manufacturer, type designation, oil mist concentration assessment capability and alarm settings. After completing the tests, the detection equipment is to be examined and the condition of all components ascertained and documented. Photographic records of the monitoring equipment condition are to be taken and included in the report. Design series qualification. The approval of one type of detection equipment may be used to qualify other devices having identical construction details. Proposals are to be submitted for consideration. The report. The test house is to provide a full report which includes the following information and documents: Test specification. Details of equipment tested. Results of tests. Acceptance. Acceptance of crankcase oil mist detection equipment is at the discretion of individual classification societies based on the appraisal plans and particulars and the test house report of the results of type testing. The following information is to be submitted to classification societies for acceptance of oil mist detection equipment and alarm arrangements: Description of oil mist detection equipment and system including alarms. Copy of the test house report identified in 11. Schematic layout of engine oil mist detection arrangements showing location of detectors/sensors and piping arrangements and dimensions. Maintenance and test manual which is to include the following information: Intended use of equipment and its operation. Functionality tests to demonstrate that the equipment is operational and that any faults can be identified and corrective actions notified. Maintenance routines and spare parts recommendations. Limit setting and instructions for safe limit levels. Where necessary, details of configurations in which the equipment is and is not to be used. Oil Mist Detectors manufacturers kidde graviner uk specs vision korea specsvision com schaller automation Germany Daihatsu oil mist detectors DAIHATSU DIESEL MFG CO LTD dhtd co jp Johnson Controls Meiyo Electric Co Ltd VISATRON OIL MIST DETECTOR SYSTEMS Engine Protection Partner AS epp no Green Instruments green instruments com Quality Monitoring Instruments Ltd QMI oilmist com