Sơn là chất lỏng có chứa bột màu, khi sơn trên bề mặt sẽtạo một màng bám dính lên bề mặt có tác dụng bảo vệ rỉ,trang trí và có tính chất đặc biệt khác.• Binders Chất Kết Dính• Solvents Dung Môi• Pigments Bột Màu• Extenders Chất Độn• Additives Chất Phụ Gia
APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions AMBIENT CONDITIONS Humidity Air Temperature Substrate Temperature Frosio 07 Ambient conditions slide # Parameters influencing the corrosion speed Atmospheric corrosion Humidity Temperature Concentration of salts Amount of air pollution, including acid rain, soot and dust particles Frosio 07 Ambient conditions slide # UnRegID/192.168.57.46/2018-03-13 17:04 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Atmospheric corrosion rate depends on humidity Corrosion rate 20 40 60 80 100 Relative Humidity, % Frosio 07 Ambient conditions slide # Atmospheric conditions Requirement during blasting and painting Surface temperature of the structure must be minimum °C above the dew point of the surrounding atmosphere Frosio 07 Ambient conditions slide # APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions ISO 8502 - Estimating probability of condensation • Cold liquid inside hull and warm air outside causes condensation • See how frames inside keeps the cold longer B-24/2-4 4847-693 Frosio 07 Ambient conditions slide # Why Temperature & Humidity are important Condensation follows the contours of the double-bottom tank Frozen overnight condensation, follows the frames of the ship Frosio 07 Ambient conditions slide # APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Purpose of climatic evaluation Evaluate the likelihood of the moisture in the air to form condensation on a substrate Frosio 07 Ambient conditions slide # Moisture / Absolute Humidity • When water evaporates, it forms water vapour or moisture in the air • We may measure this moisture as gram water per cubic meter air (g/m3) • The maximum amount of moisture that can be contained in the air depends on the temperature of the air • Warm air can contain larger amounts of moisture than cold air • The maximum moisture that can be contained in air at the various temperatures is called the Absolute Humidity Frosio 07 Ambient conditions slide # APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Absolute humidity DEFINITION: • The maximum content of water vapour in the air at a given temperature • The content will vary with temperature Frosio 07 Ambient conditions slide # At 8o C, the maximum moisture content in the air is 8.28 g/m3 Frosio 07 Ambient conditions At 20o C, the maximum moisture content in the air is 17.31 g/m3 slide # 10 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Moisture / Relative Humidity • The Relative Humidity is a measure of how much of the Absolute Humidity (maximum moisture) that the air contains, expressed as percent • If the air contains the maximum amount of moisture, it will have a Relative Humidity of 100% • If the air contain half of the maximum amount of moisture, it will have a Relative Humidity (RH) of 50% • If the air contain a quarter of the maximum amount of moisture, it will have a Relative Humidity of 25% • Question: Will air with RH=50% at 8o C have the same moisture content as air with RH=50% at 20o C? Frosio 07 Ambient conditions slide # 11 Relative humidity DEFINITION: • The ratio of – The amount of water vapour present in a given volume of air at a given temperature and – The maximum amount of water vapour which this volume of air can hold at that temperature • RH is expressed as a percentage • RH outdoors will vary Frosio 07 Ambient conditions slide # 12 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Relative humidity, RH % R.H.: Water vapour in the air as percentage of the total amount water vapour the air can contain at the same temperature Example Air at 20o C can contain 17.31 g water/m3, but the actual content is measured to 15 g/m3 What is the R.H ? R.H = 15g x 100% = 86.65% 17.31g Frosio 07 Ambient conditions slide # 13 Humidity / Dew Point • Air at 20o C and 73% RH contains 12.64 g/m3 water (12.64 as percentage of Absolute Humidity 17.31) • If the temperature drops to 16o C, it will still contain 12.64 g/m3, but the RH will increase to 92.69% (12.64 as percentage of Absolute Humidity 13.65) • If the temperature drops further to 12o C, what will happen? • At 12o C the maximum moisture content (Absolute Humidity) is 10.62 g/m3 This means the moisture content of 12.64 g/m3 is 2.02 g/m3 more than it can hold at this temperature • The consequence is that the excessive moisture will leave the air through condensation, ending up as dew on available surfaces or as rain or fog • The temperature at which a given moisture content will start to condensate is called Dew Point Frosio 07 Ambient conditions slide # 14 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Dew point DEFINITION: • The temperature at which the air becomes saturated with water vapour • At this temperature the RH = 100% and water will condense • The chance of condensation is high when the weather is changeable Frosio 07 Ambient conditions slide # 15 Dew Point / Substrate Temperature • On an early morning inspection we measure the air temperature to be 8oC and the RH to be 83% • Due to cold over-night temperature, the steel temperature of a structure to be painted was measure to only 4o C • Would this cause any problem? • At 8oC and RH 83%, the moisture content is 6.87 g/m3 • Although the general air temperature is 8o C, the air next to the steel surface will be cooled by the steel and perhaps only be 4o C as well • At 4o C the max moisture content is 6.36 g/m3 • This means that although we may not see it clearly, there will be condensation on the steel • This is why Steel Temp must be 3o C above the Dew Point! Frosio 07 Ambient conditions slide # 16 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Main rule for pre-treatment and paint application: Temperature of substrate should be at a temperature of 3oC above dew point of the air in the vicinity Frosio 07 Ambient conditions slide # 17 Measuring ambient conditions • Electronic multi-function gauge • Electronic humidity gauge • Sling Psychrometer (Sling Hygrometer, “Dry and Wet bulb”) • (Hair hygrometer, not suitable!) • Dew point calculator • Steel thermometer Frosio 07 Ambient conditions slide # 18 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course handout: Section 07 Ambient conditions Electronic humidity gauge • Needs frequent calibration • Dependent on batteries • Multi-function models will measure air temperature, surface temperature, relative humidity, and calculate dew point and T (*) (*) difference between dew point and surface temperature) Frosio 07 Ambient conditions slide # 19 Sling Psycrometer A dry and a wet thermometer put together in one unit • The difference in the measured temperatures indicate the amount of humidity: • Large difference = low RH% • Small or none = high RH% Frosio 07 Ambient conditions slide # 20 10 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Unopened, sealed mask for protection against solvents and dust • Important to select correct type of filter: Read Material Safety Data Sheet • Absorption of impurities and solvents starts when the seal is broken CD 4930 no 07 Frosio 18 HES slide # 49 Gas filters • Use gas filters to protect against solvent vapours • Filter against organic solvents must have brown colour code and/or the letter code A • Filters to be used for other gases have other colour codes and letter codes A1 Lowest degree of protection A2 Medium degree of protection A3 Highest degree of protection • Remember to replace gas filters before they become saturated! Frosio 18 HES slide # 50 25 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Dust filters • Use dust filters to protect against inhaling dust, smoke and fog • Filters will have the letter code P • Are grouped according to how coarse or fine dust they protect against P1: Lowest degree of protection P2: Medium degree of protection P3: Highest degree of protection • P2 must be used for example when we grind or wirebrush • If dust contain toxic or carcinogenic particles, P3 filter must be used Frosio 18 HES slide # 51 Combination filters • A combination of gas and dust filters is often used • This is especially the case when spray-applying paint • Filters: A2P2 or A2P3 Frosio 18 HES slide # 52 26 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazards when using paints Binders • Skin contact • Particularly Epoxy, Amines and Isocyanates may cause skin irritation and Allergic reactions Solvents: May enter the body in three ways: • By inhalation • Skin contact • Ingestion Other constituents: • Tar, Heavy metals Frosio 18 HES slide # 53 Health hazards from solvent exposure Acute effects • Headache • Abnormal tiredness • Dizziness • Nausea Long term effects • Irritability • Loss of memory • Organ damages (kidneys, liver, CNS) • Reduced reaction ability • Reduced evaluation ability Skin irritations • Eczema • Dry and cracked skin Frosio 18 HES slide # 54 27 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazards when working with surface treatment Brain and nervous system Respiratory system Heart and circulation system Kidneys Liver Skin Reproductive system Eyes Hazards: • Skin contact • Inhalation • Ingestion Gastro intestinal tract Frosio 18 HES slide # 55 Solvents Symptoms and diseases Acute symptoms • Dizziness, nausea, headache, insensibility, irritation of skin, nose and mouth Chronic symptoms • Brain damage, impact on the nervous system, respiratory system, liver, kidneys, circulation system, shaking / loss of feeling, change of behaviour / judgement Frosio 18 HES slide # 56 28 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazard: inhalation of solvents The most dangerous hazard • Solvents will be transported by the blood stream to internal organs of the body • Amount absorbed and the effect on the body will depend on: Type of solvent, period of exposure, concentration and work load • May cause damage to: Central nervous system, respiratory system, liver, kidneys and reproductive systems, Protective measures: Proper ventilation Use approved, protective mask Frosio 18 HES slide # 57 Suit covering the whole body gives good protection • Here: Disposable suit for painting with epoxy • Fresh air mask • Gloves SHE: Disposable_suit1 Frosio 18 HES slide # 58 29 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Fresh air mask • Usually used in closed compartments • Air supply from compressor placed outside the compartment • Beard may cause leaks Frosio 18 HES CD 4930 no 19 slide # 59 Health hazard: Skin contact with solvents The most frequently occurring health effects • Causes: - Reddening Swelling Drying and cracking of skin Absorption through intact skin: Some, like Xylene Absorption through damaged skin: Several, like White Spirit Protective measures: Avoid direct contact Protective clothes, gloves and boots Frosio 18 HES slide # 60 30 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Breathing of vapours and direct contact with skin must be avoided Solvents can lead to several health problems • Dry out the skin • Transportation by the blood may harm vital organs: Brain, liver, nervous system, kidneys, reproduction system etc Thinners are very harmful to the body CD 4930 no 09 Take care of your own health Frosio 18 HES slide # 61 Several mistakes are done Are you able to find them ? • SHE related mistakes • Technical mistakes? SHE \ She mistakes1 Frosio 18 HES slide # 62 31 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazard: Splash in the eyes Often occurring when pouring thinners and stirring paints • Some thinners are more dangerous than others • Consult the Safety Data Sheet • Irritates or injures the eyes Protective measures: Use approved safety glasses or a visor Flush for at least 15 minutes with tempered, clean water Seek medical assistance Frosio 18 HES slide # 63 Eye wash / shower cabinets are usually located in the vicinity of the work place • Make sure you know the location of them • Important to keep in order; function testing regularly Frosio 18 HES Øyevask Dusj, kabinett - 25 slide # 64 32 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Very simple type of first aid locker • The content may vary significantly • Usually they contain the most important remedies • Know where to find them ! CD 4930 no 16 Frosio 18 HES slide # 65 Eye wash station Sign gives two important information: • Mandatory equipment to be used in the area • Eye wash unit is placed inside the locker Frosio 18 HES slide # 66 33 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazards when working with Epoxies Hazards : Eczema and allergic reactions on the skin Liquid Epoxies with low molecular weigths (below 700) are most likely to give an allergic reaction An allergic reaction to Epoxy is irreversible Hyper-sensitive persons must stay away from epoxies Protective measures Protective clothes covering the whole body and gloves Proper cleaning with water, soap and cleaning cream Use disposable overalls Frosio 18 HES slide # 67 Health hazards when working with tar containing paints Hazards The main hazard with tar containing paints is the risk for developing cancer, especially when exposed to strong sunlight Long term exposure to vapours may damage internal organs, cause heritable genetic defects and birth defects Short term exposure to fume and vapours may cause irritation to nose, throat and eyes Splashes to skin causes irritation Protective measures Protective mask to avoid breathing vapours Protective clothes covering the whole body and gloves Frosio 18 HES slide # 68 34 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazards when working with paints containing Isocyanates The monomer is more volatile than the pre-polymer and is therefore more dangerous Isocyanates are found in Polyurethane paints Hazards Irritation of eyes skin and airways Sensitization by inhalation and skin contact Asthma Protective measures Protective mask to avoid breathing of vapours Protective clothes covering the whole body, boots and gloves Frosio 18 HES slide # 69 Health hazards when working with paints containing heavy metals Some times used in pigments, additives or driers Hazards (Metal fumes,dust from hot work) Zinc Dust and fumes: Zinc fever, chills, coughing, irritation Copper Fumes: Metal fever and chills Lead Dust and fumes Damage blood cells, Anemi, skeleton, reduced fertility and central nervous system Chromium Dust and fumes: Sensitisation, cancer Nickel / Cobalt Sensitisation General Protective measures Protective mask to avoid breathing of vapours Protective clothes covering the whole body, boots and gloves Frosio 18 HES slide # 70 35 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Health hazards when working with antifoulings • Antifoulings are generally looked upon as Toxic • Some antifoulings contain Tin • Tin may cause irritation to skin and eyes the central nervous system and effect the immune system General Protective measures Protective mask to avoid breathing of spray mist / droplets Protective clothes covering the whole body, boots and gloves Frosio 18 HES slide # 71 Label of tin gives useful information • Note the safety and health signs, Risk and Safety (R/S) phrases • Read Material Safety Data Sheet for further information CD 4930 no 11 Frosio 18 HES slide # 72 36 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Application of Antifouling Antifouling is considered toxic Operator follows Safety and health regulations: • Mask • Protective suit • Working gloves Frosio 18 HES CD 4930 no 12 slide # 73 It is important to warn other personnel about ongoing paint work • Several type of signs are used to describe the hazards • Do not forget to put up the signs before the work starts • Do not overlook warnings put up by others Frosio 18 HES CD 4930 no 13 slide # 74 37 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES How dangerous is a chemical or a paint ? Different persons will respond differently In general the hazard will depend on: The toxicity and amount of the compound The concentration and risk of exposure Frosio 18 HES The contact period with the chemical slide # 75 Conditions at the workplace Near by activities Cordon off areas Housekeeping Ventilation Waste treatment Frosio 18 HES slide # 76 38 APCPCWM_4828539:WP_0000020WP_000002 APCPCWM_4828539:WP_0000020WP_0000020 Frosio course hand-out: Section 18 HES Life Cycle Assessment Total life cycle must be evaluated • • • • • High solid paints offer many advantages Less production Less transportation Fewer coats Lower VOC Less waste Frosio 18 HES SHE \ LCA_Paints slide # 77 39