GB/T 4798.6-2012 Classification of environmental conditions Classification of environmental parameter groups and their severity levels Marine GB/T4798.6-2012 Standard compression package decompression password: www.bzxz.net
This part of GB/T4798 classifies the classification of environmental parameter groups and their severity levels to which products installed on ships are subjected. These products may be permanently or temporarily installed on the following ships: ————Ship propelled by mechanical means, including mobile offshore platforms. ————Ship propelled by non-mechanical means, including sailboats and life rafts. The specified levels apply to ships of all sizes, from yachts to trawlers, ferries, icebreakers, cargo ships (including oil tankers), etc. The areas where ships normally navigate are: ————inland waterways (canals, rivers, lakes); ————coastal waters; ——sea. It also includes ice areas where ships must navigate. The classification of environmental parameter groups and the classification of severity in this section are applicable to products installed on ships for operation, management and safety, and can also be used for other products installed in the same position in a similar way. This section does not include accidental accidents, but the possibility of accidents for products that have a significant impact on the safety of ship operation should be considered. This classification does not include the impact of water pressure on underwater products. For the classification of environmental parameter groups and their severity, please refer to the provisions on environmental conditions in IEC60092-101 for application on ships propelled by mechanical means. The classification of storage and transportation environmental conditions is specified by IEC60721-3.
class="f14" style="padding-top:10px; padding-left:12px; padding-bottom:10px;"> GB/T4798 Classification of environmental conditions Classification of environmental parameter groups and their severity classification standards currently include the following parts:
———GB/T4798.1 Environmental conditions for the application of electric and electronic products Part 1: Storage;
———GB/T4798.2 Environmental conditions for the application of electric and electronic products Part 2: Transportation;
———GB/T4798.3 Environmental conditions for the application of electric and electronic products Part 3: Fixed use in weather-protected places;
———GB/T4798.4 Environmental conditions for the application of electric and electronic products Part 4: Fixed use in places without weather protection;
———GB/T4798.5 Environmental conditions for the application of electric and electronic products Part 5: Use on ground vehicles;
———GB/T4798.6 Classification of environmental conditions Classification of environmental parameter groups and their severity classification Marine use;
———GB/T4798.7 Environmental conditions for the application of electric and electronic products Part 7: Portable and non-stationary use;
———GB/T4798.9 Classification of environmental conditions Classification of environmental parameter groups and their severity classification Microclimate inside the product;
———GB/T4798.10 Introduction to environmental conditions for the application of electric and electronic products. This part
is Part 6 of GB/T4798.
This part was drafted according to the rules given in GB/T1.1-2009.
This Part replaces GB/T 4798.6-1996 "Environmental conditions for application of electric and electronic products for marine use". Compared with GB/T 4798.6-1996, the main changes are as follows:
———Add environmental parameter levels 6K6 and 6K7 in Table 1;
———In Appendix A, A.2, the description of climatic environmental conditions 6K6 and 6K7 is added;
———Add Appendix B (informative appendix);
———Add Appendix NA (informative appendix).
This part adopts the translation method equivalent to IEC60721-3-6:1987 "Classification of environmental conditions Part 3: Classification of groups of environmental parameters and their severity Section 6: Marine use" and its Amendment No. 1 (1991-06) and Amendment No. 2 (1996-11), and makes the following editorial changes:
———"This part of IEC60721-3-6" is changed to "This part of GB/T 4798.6";
———"Technical report" is changed to "This part";
———The foreword and introduction of IEC60721-3-6 are deleted, and the foreword of the national standard is added;
———According to the requirements of GB/T 1.1-2009, Chapter 3 "Normative references" is added, and the sequence numbers of chapters and clauses are adjusted in sequence thereafter;
———Appendix NA (informative appendix) is added.
This part is proposed and managed by the National Technical Committee for Standardization of Environmental Conditions and Environmental Testing for Electrical and Electronic Products (SAC/TC8).
The main drafting units of this part are: 704th Research Institute of China Shipbuilding Industry Corporation, China Electric Power Research Institute Co., Ltd.
The main drafters of this part are: Li Zijie, Huang Songjun, Huang Kaiyun, Chen Xinxin, Sun Weixing.
The previous versions of the standards replaced by this part are:
——GB4798.6—1984, GB/T4798.6—1996.
The following documents are indispensable for the application of this document. For all dated referenced documents, only the dated version applies to this document. For all undated referenced documents, the latest version (including all amendments) applies to this document.
IEC60092-101 Electrical installations in ships Part 101: Definitions and general requirements
IEC60092-505 Electrical installations in ships Part 505: Features Mobile off-shore drilling units IEC60721-2-1
Classification of environmental conditions—Part 2: Environmental conditions occurring in nature Section 1: Temperature and humidity
(Classification of environmental conditions—Part 2: Environmental conditions appearing in nature—
1
GB/T4798.6—2012/IEC60721-3-6:1987
Foreword III
1 Scope1
2 Purpose1
3 Normative references 1
4 General provisions 2
5 Classification of environmental parameter groups and their severity classification 2
Appendix A (Informative Appendix) Summary of environmental conditions included in each grade 7
Appendix B (Informative Appendix) Description of environmental conditions in tropical areas specified in grades 6K6 and 6K7 10
Appendix NA (Informative Appendix) Correspondence between China's national standards and IEC standards 12
Figure 1 Typical shock response spectrum (first level maximum shock response spectrum) Figure 6
Figure B.1 Climate diagram of humid hot climate type and dry hot climate type 11
Table 1 Classification of climatic environmental conditions 2
Table 2 Classification of biological environmental conditions 3
Table 3 Classification of chemically active substances 4
Table 4 Classification of mechanically active substances 4
Table 5 Classification of mechanical environmental conditions 5

ICS 19. 020
National Standard of the People's Republic of China
GB/T 4798.6--2012/IEC 60721-3-6: 1987 replaces GB/T4798.6-1996
Classification of environmental conditions
Classification of environmental parameter groups and their severity
Classification of marine
Classification of environmental conditions--Classification of groups ofenvironmental parameters and their severities--Ship cnvironmcnt(IEC 60721-3-6: 1987,Classificationalior of environmental conditions—Part 3:Classificationalion of groups of cnvironmental parameters and their severilies-Section 6.Ship Environmental parameters classification and severity classification Appendix A (Informative Appendix) Summary of environmental conditions included in each grade GB/T 4798.6—2012/IEC 60721-3-6:1987 Appendix B (Informative Appendix) Description of environmental conditions in tropical areas is specified in grades 6K6 and 6K7 Appendix NA (Informative Appendix) Correspondence between my country's national standard and IEC standard Figure 1 Typical shock response spectrum (Grade - maximum shock response spectrum) Figure R.1 Climate of humid hot climate type and hot climate type Figure 1 Classification of climatic environmental conditions
Table 2 Classification of biological environmental conditions·
Table 3 Classification of chemically active substances·
Table 4 Classification of mechanically active substances
Table 5 Classification of mechanical environmental conditions
GB/T 4798.6—2012/IEC 60721-3-6:1987 CB/T4798 Classification of environmental conditions Classification of environmental parameter groups and their severity classification standards currently include the following ten parts: GB/T 4798.1
Electrical.1 Environmental conditions for application of electronic products Part 1! Part: Storage; Environmental conditions for application of electric and electronic products, Part 2: Transportation; GB/T4798.2#
Environmental conditions for application of electric and electronic products Part 3: Fixed use in places with weather protection: GB/T4798.3
GB/T 4798.4
Environmental conditions for application of electric and electronic products Part 4: Fixed use in places without weather protection: - GB/T4798.5 Environmental conditions for application of electric and electronic products Part 5: Use on ground vehicles: GB/T4798.6 Classification of environmental conditions Classification of environmental parameter groups and their severity classification for marine use: - GB/T4798.7 Environmental conditions for application of electric and electronic products Part 7: Portable and non-fixed use; - GB/T4798.9 Classification of environmental conditions Classification of environmental parameter groups and their severity classification Micro-air recovery inside the product; GB/T4798.10 Introduction to environmental conditions for application of electric and electronic products. This part is Part 6 of GB/T4798.
This part was drafted in accordance with the rules given in GB/T 1.1-2009. This part replaces GB/T4798.6-1996 "Environmental conditions for application of electrical and electronic products for marine use". Compared with GI3/T4758.6-1996, the main changes are as follows:
Add environmental parameter levels 6K6 and 6K7 in Table 1; add descriptions of climatic environmental conditions 6K6 and 6K7 in Appendix A A.2; add Appendix B (informative appendix);
Add Appendix NA (informative appendix)
This part uses the translation method equivalent to IEC60721-3-6:1987 Classification of environmental conditions Part 3, Classification of environmental parameter groups and their severity levels Section 6: Marine use" and its first amendment (1991-06) and second amendment The following editorial changes were made in the amendment sheet (1996-[1]):
“This part of IEC60721·3-6” was changed to “This part of GB/T4798.6”; “Technical report\ was changed to\ this part”; the foreword and introduction of IEC 60721-3-6 were deleted, and the “National Standard Foreword” was added; according to the requirements of GB/T1.1-2009, Chapter 3 “Normative Reference Documents” was added, and the chapter numbers were adjusted accordingly; Appendix NA (Informative Appendix) was added.
This part was proposed and managed by the National Technical Committee for Environmental Conditions and Environmental Testing of Electrical and Electronic Products (SAC/TC8). The main drafting units of this part are: the 704th Research Institute of China Shipbuilding Industry Corporation and China Electric Power Research Institute Co., Ltd. The main drafters of this part are: Li Zijie, Huang Songjun, Huang Kaiyun, Chen Xinxin and Sun Weixing. The previous versions of the standard replaced by this part are: GB 4798.6-1984, GB/T 4798.61996. III
1 Scope
GB/T 4798.6-2012/1EC 60721-3-6:1987 Classification of environmental conditions Classification of environmental parameter groups and their severity classification Marine
This part of GB/T4798 classifies the classification of environmental parameter groups and their severity to which products installed on ships are subjected. These products may be permanently or temporarily installed on the following ships: Mechanically propelled ships, including mobile offshore platforms. Non-mechanically propelled ships, including sailboats and life rafts. The specified grades are applicable to ships of various sizes, from yachts to trawlers, ferries, icebreakers, cargo ships (including oil tankers), etc. The normal navigation areas of ships are:
- inland waterways, canals, rivers, tidal flats); - coastal waters;
- open sea.
This includes ice areas where ships must navigate.
The classification and severity of environmental parameters in this part are applicable to products installed on ships for operation, management and safety. It can also be used for other products installed in similar locations in a similar way. This part does not include accidental accidents, but products that have a significant impact on the safety of ship operation should consider the possibility of accidents. This classification does not include the impact of water pressure on underwater products. Classification of environmental parameter groups and their severity: For application on ships propelled by mechanical means, refer to the relevant environmental conditions in IEC60092-101.
The classification of storage and transportation environmental conditions is specified by TEC 60721-3. 2 Purpose
The purpose of this part is to classify the various environmental parameter groups and their severity to which products installed on ships will be subjected under their use conditions.
This standard classifies environmental parameter groups and their severity into a limited number of levels, but its application is very wide. When adopting this standard, the lowest level required to cover the expected conditions of use should be selected. 3 Normative references
The following documents are indispensable for the application of this document. For all dated references, only the dated version applies to this document. For undated references, the latest version (including all amendments) applies to this document. IEC60092-101 Electrical installations in ships Part 101: Definitions and general requirements (ElcctricalinstallatiousinshipsPart lol,Definitions and general requirements) IFC 60092-505 Electrical installations in ships Part 505: Features Mobile off-shore drilling units (Electrical installationsinships—Part 505:Special features—Mobile off-shore drilling units) IEC60721-2-1 Classification of environmental conditions- Part 2: Environmental conditions appearing in nature Section 1: Temperature and humidity (Classification of environmental conditions- Part 2: Environmental conditions appearing in uat.ure-1
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GB/T 4798.6—2012/IEC 60721-3-6:1987Sect 1:Temperature and humidity)IEC60721-3 (all parts)Classification of environmental conditions-Part 3: Classification of environmental conditions and their severity (Classificationof cnvironmental conditions-Parl 3: Cleassifiration ol gtoups of euviranmental parameters and their severities)
IEC60721-3-0Classification of environmental conditions-Part 3: Classification of environmental conditions and their severity Introduction (Claxsiricalionofenvironmentalconlitions-- Part 3: Classification of groups ofcnvirontnellal parameters and their severities
4 General
For more detailed guidance, see IFC60721-3-0. The severity levels given in this section are unlikely to be exceeded. Only severe conditions that may affect the structural integrity and functional characteristics of the product are included.
Different parts may have different occurrence rates over a period of time. For any environmental parameter, its occurrence rate should be specified and additional provisions should be made when applied. See Figure 1, a typical shock response spectrum of a half-sine pulse (maximum shock response spectrum of the first level) showing the duration and rate of occurrence of the environmental parameters
5 Classification of environmental parameter groups and their severity levels Table 1. Tables 2, 3, 4 and 5 give a limited number of grades for climatic environmental conditions (K), biological environmental conditions (B), chemically active substances (C), mechanically active substances (S) and mechanical environmental conditions (M), respectively. For a specific product, a complete set of grades should be quoted, such as: 6K3/631/6C2/6S1/6M3.
The lowest grade 6K1/6B1/6C1/6S1/6M1. combination is the environmental conditions that products installed in weather-protected parts of non-mechanically propelled ships will be subjected to. The highest grade 6K5/6132/6C3/6S3/6M4 combination is suitable for products installed in parts of most types of ships with very severe environmental conditions.
Each grade of environmental conditions usually includes some lower grade severity data. For some environmental parameters, a specific severity level cannot be given at present.
For an overview of the environmental conditions included in each grade, please refer to Appendix A. Table 1
Environmental parameters
a) Low temperature, air
b) Low temperature, water
High temperature, air
a) High temperature, noodle
commercial temperature. Water
[) Temperature gradient change, air
air
g) Humidity change, air/water
Climate environment condition classification
25/—20
Freezing point of water"
-25/+40
25/+40
+40/ +5
-25/+40
+5/+40
—20/+40
+40/+5+40/+15+40/+15
Environmental parameters
h) humidity
(without rapid temperature change
(with rapid temperature change at high and low temperatures)air/
i) Humidity
(accompanied by rapid temperature changes under high water content) air/
k) Low phase humidity
1) Movement of surrounding medium, air
m) Precipitation
n) Lunar radiation
) Thermal radiation
p) Other sources except rain
q) Moisture
mm/min
Negligible
Negligible
Negligible
Table 1 (continued)
GB/T4798 .6—2012/IEC60721-3-6:1987, etc.
25/+35
—25/--35—25/-35+5/+30
+70/+15+70/+15:+55/+15
Wet surface
20/+30
+70/+15
. There are many products in the engine room that only require the space to be preheated for a period of time before they can work. For such products, the working low temperature should be 1 5 C, and the temperature gradient case only applies to non-operating conditions. When the air temperature is 7-40°C, the ship generally does not sail. However, during the coldest period of the year, the ship may temporarily stop at the port, and the products loaded on the ship may be in a state of added protection. In this case, the products in the non-operating state may have to withstand a low temperature environment as low as 55°C. In certain conditions in inland waterways, the ship may also sail at a temperature below -40°C. In the presence of substances such as salt or pollutants, the freezing point of water may be below 0 ℃,. The product may be connected to some heating components, which may affect the surface temperature. For example, in some machines, the extreme surface temperature may be higher. This situation must be taken into account.
. Assuming that the product is only subjected to a sharp drop in temperature (not a sharp rise in temperature), the values ​​of water content apply to various temperatures down to ℃. At various higher temperatures, it can be assumed that the relative humidity is about 100%. Tropical climate conditions are classified according to 6K6 (sensible heat) and 6K7 (dry heat). See Appendix B, Classification of Biological Environmental Conditions
2:
Environmental Parameters
) Plants in the air
b Animals in the air
Presence of molds, etc.
Presence of rodents and other animals harmful to the product Note: Products installed on the underwater part of the outer side of the hull will be subject to erosion by aquatic plants and animals (seaweed, scum, corals). 3
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GB/T 4798.6-—2012/1EC 60721-3-6; 1987 Table 3
Environmental parameters
a) Salt spray
" Sulfur oxide, SO
in water
) Hydrogen sulfide, I
d) Nitrogen oxide, expressed as the equivalent
value of NO
C) Ozone, O
Acid, Cl
R) Hydrofluoric acid, HF
h) Nitrogen,NH3
i) Sea salt
mg/nys
crn'/m
cra'/na
Classification of chemically active substances
Negligible
Obviously negligible
: Due to the loading of specific cargoes, other substances and different severe processes may exist. Oil tankers should refer to TEFC60092-515.1 Explosive gases are not considered in this section, so the technology includes, and there is no data before the month.
Existence'
. In addition to sea salt, this section does not include other water substances. For electrical products that have taken anti-sea salt measures, the impact of other water substances on them can be ignored.
Environmental parameters
a) Sand in the air
Dust sediment!
e) Smoke deposition
mg/(m\h)
Classification of mechanically active substances
Negligible
Smoke components present
Note 1: When loading specific cargo, such as powdery cargo, sand (including abrasive materials), etc., there may also be dust and other levels of dust. The distribution and chemical composition of the particle size are as important as the content of the particles (currently there is no data). Note 2: Oil droplets may be present in the cabin air, and its concentration can reach 3/㎡. The concentration near the diesel engine or the oil-water separator compartment is higher, up to 20nig/m2
Environmental parameters
) Steady-state vibration (positive vibration) 4
Acceleration
Frequency range
b) Unsteady-state vibration (including shock)
I type
Shock response spectrum peak amplitude
T type
Shock response spectrum peak amplitude
Subtype
Shock response spectrum peak acceleration
c) Angle Tilt
Rotation around the X axis (roll)
Rotation around the Y axis (pitch)
）Angular motion shake
Rotation around the X axis (roll)
Rotation around the Y axis (vertical)
Rotation around the Y axis (roll)
e）Constant accelerationwww.bzxz.net
X axis (pitch)
Acceleration
Y axis (pitch)
Acceleration
Z axis (fall)
Acceleration
GB/T 4798.6-2012/1EC 60721-3-6: 1987 Table 5 Classification of mechanical environmental conditions
13--100
18--100
28~-100
Note: This standard uses the first level maximum shock response spectrum without Ni, including the classification of non-steady-state vibration of shock (see Figure 1). Conventional marine engines generally produce sinusoidal vibrations with low-frequency components. On icebreakers, vibrations with frequencies up to 2000 Hz and intensities up to 50 m/s may occur. Due to the forces generated by the collision between the hull or propeller and the water, there are also random vibrations in the ship, but the level is very low, so random vibrations are not included.
h Shock is expressed as peak acceleration. Figure 1 is a typical shock response spectrum (the first level maximum shock response spectrum). The three mutually perpendicular coordinate axes relative to the ship are: X-axis
Y=transverse
Z-vertical
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GB/T 4798.6—2012/IEC 60721-3-6,19871.8
Half-stop pulse duration example
【Type spectrum: duration 11ms
T-type spectrum: duration 6 ms
Type frequency harmonic: duration 2.3 ms
Figure 1 Typical shock response spectrum (first level maximum shock response spectrum) Figure 1000
Frequency/Hz
A.】Overview
Appendix A
(Informative Appendix)
GB/T 4798.6—2012/1EC 60721-3-6: 1987Summary of environmental conditions included in each grade
This appendix covers some of the environmental conditions included in each grade and also refers to the several types of climatic conditions included. The environmental conditions that affect the selection of environmental parameters and their severity are most detailed in IEC60092-101. The following climate types are defined (see IFC60721-2-1 for details): - Cold:
Cold temperature;
- Warm temperature:
Dry heat:
Sub-dry temperature;
Humid heat:
Steady-state humid heat
It should be noted that if a certain level includes the table 1 environment covered by this catalog, this does not necessarily mean that each parameter of the level inserts the minimum environmental severity required to cover the environmental conditions. Note: The most extreme climate types in IF60721-2-1, namely extreme cold and extreme heat, are generally only found in inland areas and are therefore not included. However, it should be noted that ships may be subject to these climate types when navigating in inland waters (rivers, tidal flats), although this can be considered as very special circumstances.
A.2 Climate environmental conditions K
The climatic environmental conditions are divided into the following seven levels: 6K1 6K1 covers the conditions of various products installed in fully weather-protected, heated and ventilated areas after heating, excluding products in engine rooms and areas equipped with large heat dissipation equipment, and the products are not exposed to solar radiation through glass or other transparent materials. 6K1 includes condensation and steady-state climate types. 6K1 also includes products immersed in water in all waters, except for waters with extremely high permanent temperatures such as the Arabian Gulf. 6K2 In addition to the conditions included in 6K1, 6K2 also includes the conditions of various areas with heating and ventilation conditions in all climate types except cold weather before and during heating. For ventilated areas, 6K2 also includes humid heat and steady-state humid heat climate types. These products may be subjected to humidity, thermal radiation from heating elements, and solar radiation through glass or other transparent materials.
6K2 It also includes products immersed in water in waters with particularly high water temperatures. -6K3 In addition to the conditions included in 6K2, 6K3 also includes various products installed in the engine room and close to a large number of heat-generating equipment.
6K3 also includes various products near doors and ladder openings that need to be temporarily opened when loading and unloading cargo. 6K4 In addition to the conditions included in 6K3, 6K4 also includes non-ventilated parts that are exposed to solar radiation, rain and water flow except for cold climate types, and also includes products for light climate protection in all climate types except cold, but does not include sailing in waters with abnormal rainfall and hurricanes.
The product may also be exposed to direct solar radiation and water flow, but does not include the scouring of large waves. 7
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GB/T 4798.6-2012/IEC 60721-3-6:19876K4 also includes products installed in heating parts of the machine. -6K In addition to the conditions included in 6K4, 6K5 includes products installed in cold climate types, in weather-protected but not heated parts and in non-weather-protected parts, and also includes products installed in refrigerated cabins and in waters with abnormal rainfall and hurricanes without weather protection, as well as products that are affected by large waves. 6K6 6K6 represents hot and humid weather conditions (tropical hot and humid weather types, such as tropical rain forest areas), -6K? 6K7 grade indicates dry heat, sub-dry heat and extreme dry heat outdoor climate conditions (tropical hot climate type, such as desert) A.3 Biological environmental conditions H
Biological environmental conditions are divided into the following two grade marks: 6B16B1 includes various devices on ships sailing in waters without special animal and plant hazards, including various devices installed in cabins on other ships where the structure is unlikely to grow mold or be harmed by animals; -6B2 In addition to the conditions included in 6B1, 6B2 also includes various unprotected devices on ships sailing in waters that may be long-term or subject to animal harm.
A.4 Chemically active substances C
Chemically active substances are divided into the following three levels: 6C1-6C1 includes various devices that are not exposed to salt spray, engine exhaust and emissions from adjacent industrial pollution sources, and have complete weather protection. It also includes devices on deck that have protective measures for engine exhaust when sailing in inland freshwater waters and not sailing in waters near industrial areas that emit large amounts of air pollutants: 6C2 In addition to the conditions included in 6C1, 6C2 also includes various devices that are exposed to salt spray and engine exhaust and have complete weather protection;
--6C3 In addition to the conditions included in 6C2, 6C3 also includes various devices without weather protection, and also includes various conditions on ships sailing in waters near industrial areas that emit large amounts of air pollutants. A.5 Mechanically active substances S
Mechanically active substances are classified into the following three levels: 6SI 6SI includes various devices with protection measures against sand, dust and soot; -6S2 In addition to the conditions included in 6S1, 6S2 also includes weather protection and various equipment for dusty deck cleaning areas, and also includes various parts of virgin gas (smoke charcoal). 6S3 In addition to the conditions included in 6S2, 6S3 also includes various devices without weather protection, including various devices of ships sailing near deserts.
A.6 Mechanical environmental conditions M
Mechanical environmental conditions are classified into the following four levels: -6M1 6M1 only includes devices on non-powered ships. -6M2 In addition to the conditions included in 6M1, 6M2 also includes devices on powered ships with a deadweight of more than 1000t, but with a deadweight of less than 200010t, excluding devices at the stern of the ship. 6M does not include devices directly connected to the loading reciprocating machine. -6M3 In addition to the conditions included in 6M2, 6M3 also includes the deadweight less than 1000t. Ship-devices and tail weight small Ding 8
GR/T 4798.6--2012/IEC 60721-3-6: 198720001 Ship accommodation devices, also includes direct loading systems, container rails and equipment connected to the crane, and dredging equipment,
6M4 In addition to the conditions included in 6M3, 6M4 also includes equipment directly connected to reciprocating machinery. iiKacaQiaiKAca=
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