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Cleanroom Supplies

  1. Safe Cleanroom Practices

    Safe Cleanroom Practices

    How To Guide: Cleaning Lab Glassware Safely

    Laboratory glassware has frequent contact with a range of substances on a repeated basis and ensuring that equipment can be re-used safely requires a robust cleaning process. Effective cleaning also helps to prolong the life of the products used and protects the validity of future work. The act of cleaning lab glassware for reuse is often referred to as re-processing and can be carried out manually, with the use of automated washing equipment or a combination of both. This post originally printed here outlines the core steps to effective re-processing as well as general tips for cleaning glassware safely.

    Reprocessing Laboratory Glassware Explained

    A complete cleaning, or re-processing cycle typically consists of four stages, although not all are always necessary.

    1. Initial cleaning – This step ensures the removal of any adhering contamination from the surfaces of laboratory glassware, using process chemicals if necessary. 

    2. Neutralisation – If required, this process is undertaken to neutralise the residues of any process chemicals employed on and in the surfaces of laboratory glassware during cleaning. As alkaline process chemicals are typically used in cleaning processes, acidic chemicals are generally used for neutralisation.

    3. Rinsing – This step removes any remaining dissolved / detached contamination and the process chemical employed from the surfaces of the glassware

    4. Disinfection – This stage is only required if the safety classification in the laboratory or specific process demands it. The aim of disinfection is to reduce the number of pathogenic germs and active viruses on the surfaces of laboratory glassware and, if applicable, to reduce the contamination to a degree which is accepted as being safe. 

    Basic Tips for Cleaning Lab Glassware

    1. Whether a full re-processing is taking place or not, and whether it is manual or automated, there are a number of tips that can help ensure lab glassware and plastic coated glassware is cleaned effectively and safely. Here are twelve tips to help you in your daily work.

    2. Washing machines may be used to enable automated re-processing. Support racks on the washer must be well maintained. The support pins should be coated with a non-abrasive material to prevent metal to glass contact and scratching.

    3. For manual washing, use only plastic core brushes that have soft, non-abrasive bristles. Soft, clean sponges or other wiping materials may be used. Do not use brushes or wiping material with abrasive cleaners. Scouring pads will scratch glass and should not be used.

    4. Inspect your glassware after cleaning and discard it if scratched, chipped, cracked or damaged in any way.

    5. Many commercial glass cleaners are available. Follow the manufacturers’ directions for the use of these products since some are corrosive and can damage laboratory glass.

    6. Organic solvents are acceptable cleaning agents when conditions warrant their use.

    7. Do not soak plastic-coated glassware for long periods of time and this can shorten the life of the coating. Do not allow used plastic-coated glassware to sit unwashed for long periods of time, as this will make cleaning more difficult.

    8. Do not place metal or other hard objects, such as spatulas, glass stirring rods, or brushes with metal parts, inside the glassware. This will scratch the glass and can cause eventual breakage and injury.

    9. Do not use strong alkaline products and hydrofluoric acid as cleaning agents. They are glass dissolvers and can damage the glassware and eventually cause breakage which can result in injury.

    10. Do not use any abrasive cleansers, including soft cleansers as these can also scratch the glass and if use repeatedly can cause eventual breakage and injury.

    11. Do not place hands inside glassware while wearing any jewelry, particularly diamond rings, as these will score the inside of the glassware, resulting in damage that could lead to eventual breakage and injury.

    12. Do not heat glassware to temperatures above 400°C to burn out carbon residues. This will result in the introduction of permanent stresses in the glass that will eventually cause the glassware to break, resulting in possible injury.

    13. Plastic-coated glassware should not be cleaned with harsh, chemical grade detergents. Instead, use a non-abrasive grade detergent. If using a dishwasher or dryer, avoid temperatures greater than 110°C (230°C). Scouring pads and brushes are not recommended for use on plastic-coated glassware.

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  2. Advanced Cleaning Mechanisms: Metallic Parts, Bath Monitoring

    Advanced Cleaning Mechanisms: Metallic Parts, Bath Monitoring

    Question: We are using a bath of Alconox powder for cleaning several metallic parts.  We have found that both the concentration of Alconox, along with a set duration brings about the correct end result.  As the wash solution is created at the beginning of each working shift, a gradual ‘weakening’ of the process occurs. In some instances, we resort to manually replenishing the tank with a fresh mix mid-shift. 

    Would you have any general advice?

    Answer:  Alconox® Powdered Precision Cleaner, along with essentially all of our other aqueous detergents are great for using in a cleaning bath (soaking mechanisms) or ultrasonic bath.  (This of course assumes the right chemistry for the right residue/substrate is chosen.) The mechanism of depleting your bath varies with types of residues.  A hydrocarbon or silicon oil/grease will typically deplete the emulsifying capacity of the detergent. This emulsifier type of depletion is best detected by conductivity.   A metal oxide, inorganic particulate residue will deplete the dispersants and chelating agent capacity which can also be detected to a degree by conductivity and somewhat better by monitoring loss of total alkalinity.  A natural oil (triglycerides) or acid residue will deplete the emulsifying capacity as well as the buffering capacity of the detergent.  The natural oil residue depletion can be detected by conductivity, total alkalinity titration, or pH monitoring.  All types of residues, if they are fairly uniform and the surface area per basket of parts or individual part is fairly uniform, can use a method of parts or basket counting to control a bath. There are several methods of monitoring a bath to try to determine when to refresh it.  They all have their pros and cons.

    1. You can monitor conductivity by checking the conductivity of a freshly made solution compared with the bath as it is used at constant volume.  Constant volume is kept by refreshing any lost volume of solution due to dragout (solution leaving with removed parts) or evaporation.  You need to be aware by observation if your system loses volume substantially due to dragout or due to evaporation.  If evaporation is the dominant mechanism of loss of bath volume, then add makeup water to restore volume before taking your controlling conductivity measurement.   If dragout is the primary reason for loss of volume, then restoring volume before taking your controlling conductivity measurement is not needed.  In general a bath at 125F/50C or lower will not lose much to evaporation.  At higher temperatures, evaporation plays are larger role. 

    The idea is that with dragout, the whole bath is being removed and the concentration of detergent, and in particular the concentration of dissolved and emulsified residues, is not being concentrated by evaporation of water.   In a high evaporation, higher temperature cleaning system, the evaporation of water increases the concentration of dissolved and emulsified residues, thereby giving false positive high conductivity readings.  By restoring the volume of evaporated water, you get a more representative conductivity reading.  In either case, a 10% increase in conductivity represents a good guideline of when to change out the bath.  Note that for less critical cleaning or when working with highly conductive residues, consider a 15% increase in conductivity for when you change out the bath.

    2. You can titrate total alkalinity in the bath to monitor depletion of the cleaning solution.  Again for best accuracy, restore bath volume with water in a high evaporation system.  This type of control works best if the residues being removed are alkaline labile such as natural oils that are hydrolyzed or saponified, or other types of alkaline depleting residues.   If you have mostly hydrocarbon oils and assorted insoluble particulates, using total alkalinity titration my not be effective.  Procedures for total alkalinity titrations can be provided upon request.

    3. If the parts being cleaned are fairly uniform in the level of residue and similar in surface area being cleaned per basket of parts, you can control a bath by counting the numbers of baskets of parts, or numbers of parts being cleaned.  Empirical observations of when the bath starts to perform less well, can lead you to a number of baskets or parts that can reasonably and reliably be cleaned before you have to change out the bath.

    4. With Alconox detergent, we do not recommend monitoring pH as a means of bath control.  Alconox powder is highly buffered and needs quite a heavy load of acid residues to overcome the buffering and cause a drop in pH.   If you know you have a highly acidic residue, and no other means of control seems to work for you, then you could consider monitoring pH.  While controlling for evaporation volume with water additions to maintain constant volume, you can measure pH and a drop of approximately 0.3 pH units would indicate a time to change the bath.

    Note that another reason for bath depletion is if the bath temperature drops over time.  A drop of 10C (~20F) in the cleaning bath will cause a 50% drop in cleaning speed.  You should try to use thermostats to control bath temperature to avoid cleaning depletions due to loss of temperature.

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  3. How To Clean Shears and Trimmers That Have Cannabis Residue

    How To Clean Shears and Trimmers That Have Cannabis Residue

    Q: We are looking to clean stainless steel shears and trimmers that have cannabis residue. We have heard great things about Alconox detergents. Will they work here?

    A: Yes, absolutely. Ensuring that between batches, equipment is robustly cleaned to avoid cross contamination is essential to ensure your product stays pure.

    The way it should be.

    We would recommend soaking, scrubbing or ultrasonic tanks for the blades of the shears and trimmers in warm to hot, 2-5% Detonox® Ultimate Precision Cleaner or Alconox® Powdered Precision Cleaner.

    Follow with thorough rinsing, with the first rinse being at or around the same temperature as the wash. In this way, we can avoid having the emulsions that form become thermally shocked and risk redepositing the oily, waxy residue.

    Note: Many customers have reported success using Alconox powder as a grit or paste (small amount of water added to powder). This makes for a great scrub for trimmers and other tool spots that have a lot of build up and need heavy “elbow grease.”

    As always hotter water will help! For washer cleaning of your shears and trimmers, we would recommend Alcojet® Low Foaming Powdered Detergent or Keylajet® Low-foaming Chelating High Alkaline Liquid for powder and liquid dispensing washers, respectively. The same warm to hot, 2-5% solutions can similarly be used here. In both manual and washer applications, the detergent amount, time and temperature can be optimized from there.

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  4. Disposal of Alconox Inc. Detergents

    Disposal of Alconox Inc. Detergents

    Q: What is the proper way to dispose of your detergents? Are they drain safe?

    A: Detergent disposal in a proper manner is an integral part of a robust cleaning program regardless of scale or industry.

    Alconox Inc. detergents are biodegradable and without added softeners, brighteners, dyes or fragrances. This ensures a free-rinsing, residue-free cleaning process. Our detergents between pH 2 and pH 12.5 are all classified as non corrosive based on 40 CFR 261.22. (As a matter of comparison, common household toilet cleaners can be as low as ph 1 and oven cleaner can be as high as ph 13-14.) Overall, the Alconox Inc. detergent portfolio is safe to go to drain.

    As a global distributor of detergents, covering many thousands of municipalities, we certainly recommend reviewing local regulations which may or may not be more stringent for the detergent disposal. Review of our SDS and technical bulletins can assist your Environmental Health & Safety Manager, or equivalent, in making any necessary determinations. Other considerations would include what residues are being removed as those may be the more concerning waste depending on industry/application. We are involved in fields ranging from blood and protein residue removal, to radioactive decontamination. It rarely is the aqueous detergent that is of concern.

    Foaming is another aspect to monitor. While certainly not hazardous, it may be unsightly and can best be resolved by controlling the flow of the detergent to waste. This is especially true with our higher foaming detergents; used in manual cleaning including scrubbing, soaking and ultrasonic.

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  5. Safe Cleanroom Practices

    Safe Cleanroom Practices

    Safe Cleanroom Practices

     

    safe cleanroom

    When entering the cleanroom, always:
    Enter only through the ante-room – no shortcuts.
    Walk across the tacky mat to clean the soles of your shoes.      
    Wear shoe covers.
    Wear cleanroom garments (frock or bunny suit).
    Wear a bouffant cap & beard cover (if necessary). 
    Wear gloves (if necessary).
    Wipe down any hand or power tools. 

    When inside the cleanroom:
    Never remove any cleanroom garments.
    No unnecessary paper products or paper bags.
    No wooden pallets, ladders or wood-handled tools. 
    No cardboard boxes or packing peanuts.
    No pencils or erasers – pens only.
    Never bring in unclean or rusty tools.
    No Food, No Drink, No Chewing Gum – ever. No excessive or dangling jewelry.
    Do not raise your sleeve to observe your watch – checkout the wall clock within the cleanroom.

    Whenever leaving the cleanroom, always:
    Exit only through the ante-room – no shortcuts.
    Remove cleanroom garments within the ante-room.
    Carefully hang up garment(s).
    Properly store or dispose of bouffant & shoe covers.
    Take your time – haste does make waste.

     

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    Lab Coats on sale here

     

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  6. Linear Guides for Cleanrooms

    Linear Guides for Cleanrooms

    Cleanrooms play an essential role in contamination-sensitive applications such as semiconductor fabrication, pharmaceuticals, optics, medical devices/life sciences, and many more. Cleanrooms control the number of particulates in the air (such as dust, microbes, and aerosols) to avoid compromising cleanroom processes and products made there. Standards for these enclosures are tight, especially for motion systems used in them. But following a few basic techniques lets designers use linear motion devices while maintaining an appropriately clean environment. Cleanrooms are classed according to the number of particles of a specific size per unit volume of space. To control the size of particulates in a cleanroom, designers filter and minimize the introduction of new particulates from personnel, materials, and equipment. Controlling particulate generation can be a challenge, particularly when the cleanroom encloses machinery. Micro-lithography, for example, uses slots of robots and other motion devices. Moving equipment that is improperly specified can generate fresh particles. With proper techniques, however, a linear motion devices can support operations in a Class 100 cleanroom as easily as on a factory floor.

    Controlling Contact

    Linear bearings inherently involve metal-to-meal contact. Ball-style bearings, for example, generate metal fragments by having balls contacting each other as the they roll and turn in their rings. One way to minimize that contact is to enclose and separate the balls in a cage. Ball cages are plastic or polymer structures that maintain separation between balls without altering their friction-reducing capabilities. There is a common misconception that ball cages increase prices or leadtimes, but that is not generally the case. For the most common bearings there is no price difference for adding cages. This makes ordering linear guides with ball cages a smart way to increase guide life and improve cleanroom performance.

    Preventing Corrosion

    Corrosion is another source of particulates. Standard-grade carbon steel oxidizes in the presence of moisture to create rust. This is a concern for applications such as semiconductor and laboratory analytics, which involve reagents, and even manufacturing processes that take place in humid environments. In these types of cleanroom applications, corrosion control measures such as the use of appropriate grades of stainless steel and anticorrosion coatings like hard or black chrome. Although these measures are effective, they can add significantly to a part’s leadtime. When orders come in for bearings with an anticorrosion coatings, for example, manufacturers do not modify bearings already in stock. Instead, they build the bearings from scratch, coating each element before assembling the them. This typically extends leadtime to several months. The alternative is to work with local suppliers to disassemble standard bearings, coat, and then reassemble them. The method can substantially reduce leadtimes but must be approached with caution. Working with bearings at this level requires skill and should only be undertaken with experienced technicians who can guarantee results.

    Managing Lubrication

    A final consideration for cleanroom bearings is the choice of lubrication. Although standard greases are designed to reduce rolling resistance, they can spatter and generate particles. Cleanroom greases are specifically formulated for low dusting. 

    Getting linear bearings packed with cleanroom grease is not as easy as it sounds. Manufacturers don’t simply pull a stock part from inventory and change out the grease. Instead, when the order comes in, they build a linear bearing from scratch and inject the appropriate grease at the end. As a result, ordering these parts can involve a leadtime of several months. From the OEM perspective, buying a stock part and swapping out the grease seems like a reasonable solution, but it can actually be problematic.

    One cardinal rules of lubrication is that greases should not be mixed. Doing so can breakdown the lubrication, damage parts, and lead to premature failure. It is difficult to remove all of the grease from a caged bearing before replacing the grease. The process typically requires special degreasing tanks to remove all residue.

    Trust Your Vendor

    Cleanroom applications are typically high-value operations with a high costs for  downtime and scrap. To protect operations and maximize operation equipment expenses (OEE), specify linear bearings that can operate in cleanroom environments. Minimize dust generation by choosing caged bearing guides and specifying corrosion resistant components where appropriate. Be sure to use cleanroom greases and take advantage of local expertise to minimize leadtime. Most important, work closely with your vendor to ensure you make the best choice of components and processes to ensure the success of your application.

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  7. Cleanroom Requirements and Classifications

    Cleanroom Requirements and Classifications
    This infographic was created by Technical Safety Services, a cleanroom testing company
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  8. Water Spots on Medical Devices After Washer Cleaning

    Water Spots on Medical Devices After Washer Cleaning
    Q. We are washing stainless medical devices in a washer and are getting water spots. We are using Solujet and Citrajet. What’s causing this problem? A. Water spots typically occur because of two main reasons: the orientation of the parts in the washer is trapping dirty wash water and/or detergent dosing is insufficient. If any items being washed have a shape that can retain dirty wash water, it can sometimes get carried into the next rinse cycle and spread all over all the items being washed. An example of a such a shape would be “U” shapes or cups. Then the parts gets dried and the residue from the dirty wash water leaves water spots. To solve this, load the items in a way to tilt them so they drain completely and do not carry dirty wash water from the wash cycle to the rinse cycle. If this is not an issue, then consider detergent dosing. If you are washing with hard tap water (high in calcium, magnesium and iron), and you are under-dosing the detergent, then there may not be enough chelating agent to tie up the hardness ions. In this case, these ions will precipitate out as metal oxides/hyrdroxides/carbonates that then do not rinse easily and can lead to water spots. Be sure to use at least a 1% Solujet® Low Foaming Phosphate Free Detergent wash solution (10 mL/L) and 1% Citrajet® Low Foaming Acid Cleaner rinse solution (10 mL/L). Also consider using deionized, RO, or distilled water for rinsing, and even washing, which can help completely avoid this problem. Note that high quality water is less important for the wash step.
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  9. REDEFINING TEPID: TOP 5 REASONS TO PROVIDE THE RIGHT TEMPERATURE WATER TO EYEWASHES AND SHOWERS

    REDEFINING TEPID: TOP 5 REASONS TO PROVIDE THE RIGHT TEMPERATURE WATER TO EYEWASHES AND SHOWERS



    When it comes to emergency shower and eyewash equipment, a ten-degree difference could make all the difference. The right water temperature is critical to ensuring medically suitable results for an injured person. Current ANSI Standards (American National Standards Institute) are referenced by the Occupational Safety and Health Administration (OSHA) when evaluating facilities and mandate a temperature range defined as “tepid.”

    This is clarified as a 40-degree temperature range for flushing fluids spanning from 60°F to 100°F [16°C to 38°C].

    REDEFINING TEPID: TOP 5 REASONS TO PROVIDE THE RIGHT TEMPERATURE WATER TO EYEWASHES AND SHOWERS WHY YOU NEED TO PROVIDE THE RIGHT WATER TEMPERATURE TO USERS VICTIM COMFORT

    According the ANSI Z358.1-2014, fifteen minutes is the required length of a drench cycle when using emergency shower and eyewash equipment. It’s a necessary amount of time to ensure the chemicals and contaminants are properly flushed out of the eyes and off the face and body. But water that is too hot or too cold can drive an injured user out of the emergency equipment much too soon, while also risking exposure to additional injury. Providing tepid water to a user helps cool chemical burns, prevents chemical absorption, and encourages the removal of contaminated clothing that can act as a barrier.

    SCALDING
    The body’s biological response to hot water is for its pores to open, which could potentially increase absorption of contaminants into the skin. Plus, water that is too hot can scald the soft tissue of the eyes and delicate skin causing further damage. Less often addressed are chemicals that can trigger an aggravated chemical reaction when it comes into contact with water at particularly higher temperatures. Cavviot: Review SDS (Safety Data Sheet) of chemicals that could become more of a hazard by reacting violently to warmer temperatures. These types of chemicals require setting the water temperature to a specific degree to prevent chemical reactions.

    HYPOTHERMIA
    Water that is too cold can lead to hypothermia on top of the original chemical exposure. Studies have also shown that a fifteen-minute exposure to water temperatures in the lower end of the ANSI-mandated temperature range (60°F) can cause cold shock. This is the reaction that the body has upon exposure to cold water, and potential side effects including cardiac arrest. Water at low temperatures is also far more likely to prevent an injured worker from drenching for a decontamination period that would prove medically effective. In addition, some severely hazardous chemicals will not dilute to safe levels unless a longer flush is administered such as strong alkali’s that suggest a 60-minute flush.

    BACTERIAL GROWTH/ LEGIONELLA
    Certain water temperature ranges are more prone to bacterial growth, which can present serious health risks to those exposed. Legionella bacteria growth thrives between 95°F and 115°F, a range that overlaps the current ANSI tepid water range. While the ANSI standard does require a weekly flush to clear all piping sections that lead to the emergency shower and eyewash station, avoiding temperatures that harbor bacteria is a valuable step in limiting potential exposure.Water that is too hot or too cold can drive an injured user out of the emergency equipment much too soon.Legionella bacteria growth thrives between 95°F and 115°F, a range that overlaps the ANSI tepid water range. Water too hot can increase absorption of contaminants into the skin. Water too cold can lead to hypothermia.

    DATED STANDARDS
    In 1998, the ANSI Standard introduced tepid water as a requirement of emergency shower and eyewash systems. In the 2004 revision, the standard was further clarified, stating that medical recommendations warned against flushing fluids exceeding 100°F, which “have proven to be harmful to the eyes and can enhance chemical interaction with the eyes and skin” (ANSI Z358.1-2004). The standard also stated that “recent information indicates that a temperature of 60°F is suitable for the lower parameter for tepid flushing fluid without causing hypothermia to the equipment user.” However, no source information accompanied these statements.This standard was maintained in the 2014 revision, but more insight into both the biological response to water temperatures at the low end of this temperature range and the ideal growth temperature of legionella bacteria should dictate a change.

    RECOMMENDATIONS
    Each piece of emergency equipment must be available to provide proper first aid in the event of an emergency, and a revised water temperature range between 70°F and 95°F can help ensure medically effective results:

    INCREASING THE MINIMUM FLUSHING FLUID TEMPERATURE TO 70°F WILL:
    • Help encourage users to use the equipment for the full fifteen-minute flush cycle

    • Protect against cold shock that could lead to cardiac arrest

    • Advocate for the removal of contaminated clothing

    DECREASING THE MAXIMUM TEMPERATURE TO 95°F WILL:
    • Avoid temperatures known to harbor specific bacteria growth

    • Prevent scalding of the eyes and skin

    • Reduce the chances of an increased chemical reaction


    A majority of outdoor or extreme climate equipment installations would require additional infrastructure to meet the tepid water range for water delivery. Emergency shower and eyewash manufacturers offer various tempering solutions including Thermostatic Mixing Valves. Setting Thermostatic Mixing Valve temperatures between 80°F and 85°F not only meets current ANSI Standards, but also ensures compliance should future revisions take into account these recommendations. To assist in the appropriate installation and performance of its emergency systems, Haws recommends a much tighter temperature range. Thermostatic Mixing Valves on Haws emergency shower and eyewash systems are set between 80°F and 85°F. It’s a narrow, yet necessary interpretation of ANSI Z358.1, which defines a suitable temperature range as 60°F to 100°F. This defined range fits neatly into a new recommended range of 70°F to 95°F, temperatures that ensure both victim comfort and appropriate equipment use, as well as a reduced risk of bacterial exposure.Studies show that when proper first aid is provided, an average of 7.7 days of hospitalization were necessary, whereas those who did not receive proper first aid required an average of 20.5 days of hospitalization

    Emergency shower and eyewash systems are designed for emergency scenarios, but simply providing them isn’t enough. The equipment needs to perform in accordance with the most current ANSI Z358.1 Standard and work as intended at any time, while providing a comfortable and appropriate temperature water delivery.

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  10. Passivate: Citric Acid Option with Citranox and Citrajet Detergents

    Passivate: Citric Acid Option with Citranox and Citrajet Detergents

    Q. Surface contamination interferes with formation of protective oxide coating on stainless steel thereby leaving it open to corrosion.

    The stainless steel needs passivation. Can Alconox, Inc. help?

    A. Stainless steels are autopassivating in the sense that the protective oxide passive film is formed spontaneously on exposure to air or moisture.

    Surface contamination, may interfere with the formation of the passive film. The cleaning of these contaminants from the stainless steel surface with citric acid detergent will facilitate passivation by allowing the oxygen access to the surface.

    Passivate by immersing the stainless steel in either a 30% solution (300mL/L) of Citranox® Liquid Acid Cleaner and Detergent or Citrajet® Low-Foam Liquid Acid Cleaner/Rinse at any of the following combination of time and temperature: 70-120 deg F (21-49 deg C)/20 min, 120-140 deg F (49-60 deg C)/10 min, or 140-160 deg F (60-71 deg C)/4 minutes.

    Rinse thoroughly immediately after passivation.

    Final rinse should be in clean water with a final reading of less than 200 ppm total solids. Neutralization is not required.

    Air oxidation will complete passivation.

    Note that this process conforms to ASTM A967-01 Standard Specification for Chemical Passivation Treatments of Stainless Steel Parts.

    If desired, Ferritic and Martensitic steels can be treated with 5% sodium dichromate at 150 deg F (65 deg C) for 30 min to accelerate surface oxidation to form passive oxide layer.

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