Worker Safety

• Flammability
• Enclosed Areas
• Protective Equipment
• Toxicity and Inhalation Risks
  • Background: Toxicity Explained
• Exposure Limits for MicroCare Products
• Understanding the Bromothane^™ Toxicity Rating
• Storage and Handling of MicroCare Cleaners

Flammability of the MicroCare Fluids

First, the MicroCare cleaning products have no flashpoint and are nonflammable. This makes them very safe to ship, store and use. In addition, they are extremely stable. This means that under normal conditions during storage and use the products will not deteriorate in any way. With the exception of Vertrel® XSi and BromoBooster™  concentrate, these products are all true azeotropes or near-azeotropic blends which retain their proportions across all the normal temperature ranges, even when distilled. This specific feature makes them ideal for use in heated cleaning systems, and especially in vapor degreasers.

Specifically, none of the MicroCare precision cleaners exhibit a tag closed cup flash point. The products are rated as nonflammable according to the Tag Closed Cup Method ( ASTM-D-56). Because of these test results, none of the solvents are classified as flammable liquids by either the National Fire Protection Association (NFPA) or the Department of Transportation (DOT).

In addition, some of the cleaners include flammable constituents and therefore have "vapor flammability limits." This means that it is theoretically possible to find a combination of vapors and oxygen that could sustain combustion under very unusual circumstances. These normally are described as a "lower explosive limit" (LEL) and the "upper explosive limit" (UEL). For example, in the event of a spill or leak the mixture of air and solvent vapors around the spill may fall between the LEL and the UEL and, therefore, become flammable. These vapor flammability limits are presented on each Product Spec sheet and each MSDS sheet.

However, Vertrel^® XSi and the BromoBooster^™ concentrate are flammable mixtures. These two products need to be handled with all the normal care and caution used on any flammable material, such as isopropyl alcohol. It's worth noting, however, that neither of these products are a solvent product per se.

So, it is safe to heat the MicroCare cleaners, the Vertrel^® products and the Bromothane^™ cleaning agents in vapor degreasers. In fact, they are designed for it!

However, these products can decompose if they come into contact with very high temperatures, such as an open flame or the hot surfaces in space heaters. Decomposition products include irritating and toxic compounds such as hydrogen bromide. If this happens, the vapors will be hazardous. At that time the work area should be evacuated and ventilated to prevent personnel exposure. Anyone exposed to the decomposition products should be taken to fresh air and given medical attention immediately.

To prevent the decomposition of the cleaning agents, operating conditions should be held within the recommended guidelines. Any contact with a high heat source – such as open flames, heating elements or hot surfaces – should be avoided. Vapor degreasers should be equipped with interlocks that automatically prevent the heating coils from becoming uncovered. If there is evidence that decomposition is taking place, shut down the system, provide ventilation to clear the area of decomposition products, and leave the area to get fresh air.

NOTE: the irritating aroma of the vapors will generally alert people and force them to leave the area long before any hazardous effects might occur.

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Working with Solvents in Enclosed Areas

Vapor degreasers filled with the MicroCare cleaners are very safe cleaning systems. However, during maintenance technicians may be exposed to unusually high concentrations of vapors. Similarly, in the event of a spill, workers may be exposed to prolonged inhalation of high vapor concentrations. These situations require slightly different procedures than merely working near a well-tuned cleaning machine.

First and foremost, if there is any concern that a very high concentration of vapors may exist (such as during a spill) supervisors should follow the safety regulations specified by O.S.H.A. in the U.S. Code of Federal Regulations CFR 29 for safe tank entry procedures. These documents specify state-of-the-art procedures, and will provide the best information so the clean-up may proceed safely. Every company's Health and Safety manager or O.S.H.A. should have the details on these specifications.

Users should be aware that the highest concentration of solvent vapors will be near the ground because the vapors are four to eight times heavier than air. These heavy vapors will displace the air in a confined space. Inhalation may cause suffocation and death due to oxygen deprivation. In the event of a spill, and before attempting any remediation or control measures, evacuate the area and thoroughly ventilate the work spaces. Companies may chose to monitor the individual exposure levels during the clean-up to enhance worker safety.

Prior to performing maintenance on the cleaning system, or before entering a confined space, a pit or a low-lying area, open all hatches or vents on the equipment and ventilate the equipment and the area thoroughly. In addition, never go into a confined space along – always work with a buddy in case there is a problem. This is crucial!

To ventilate a confined area, use fans to force air down to the lowest point in the area. Monitor the composition of the atmosphere in the area. Before it will be safe to enter the area safely without an independent air supply, the oxygen content should be at least 18.5% and the concentration of solvent vapors should be below the AEL for the solvent in use.

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Protective Equipment for Eye and Skin Contact

Skin and eye contact are the most common risks. Impervious gloves and protective clothing really are the best choice if there is any potential for skin contact. While casual and intermittent skin contact with the MicroCare cleaners is not a problem, it is not a recommended practice. Common sense strongly recommends that prolonged or repetitive skin contact with any solvent or chemical should be avoided. These solvents remove natural oils from skin, and are particularly adept at dissolving natural oils. This can result in the temporary drying, itching, swelling and roughening of the skin, a condition called temporary local dermatitis. Healing is rapid after the exposure ceases.

Impervious gloves and protective clothing are strongly suggested if there is any potential for skin contact. Gloves, splash goggles, aprons (when handling open drums), and safety shoes with steel toes also are highly recommended. As a general rule for MicroCare products, Viton^® gloves, butyl rubber or other materials to provide optimal protection. Chose the powderless option if it is important to control nonvolatile residues in the production process. These are widely available from quality distributors everywhere.

There is a really good web site which has excellent technical data about the huge array of glove choices available on the market. It's organized by the Office of Radiation, Chemical and Biological Safety (ORCBS) of the Michigan State University, so it's not tied to any one manufacturer or brand. The site suggests the best type of glove to use based on the materials and chemicals in-use. In the color chart, look for gloves rated white or green.

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Toxicity and Inhalation Risks from the Cleaning Fluids

The vapors from the MicroCare cleaners are generally not hazardous unless there is significant over-exposure to them, but monitoring the vapors is an important part of a company's worker safety program. The hazards associated with solvents, particularly n-propyl bromide, vary by the extent of the exposure. Short-term over-exposure can lead to skin and eye irritation, dizziness or headaches. Long-term tests show effects on fertility in laboratory animals.

MicroCare requires an annual air quality monitoring program as part of the MicroCare product stewardship program and recommends it for the other cleaners as well. All Bromothane^™ users are required to conduct a simple workplace exposure test using air monitoring badges to assure worker safety. This is an excellent and simple process and is applicable to the other MicroCare cleaners besides just the Bromothane products.

The exposures badges are an easy way for the employee to determine the exposure to a chemical. While wearing the badge on the collar of their shirt, each employee simply goes about their daily routine. After wearing the badge for eight hours, the badge is sent to an independent lab to determine exposure levels.

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Exposure Limits for the MicroCare Products

In general, the MicroCare cleaning products and the Vertrel^® specialty fluids can be considered very safe for workers and relatively “non-toxic.” The Bromothane^™ cleaners do have some special toxicity concerns and MicroCare has implemented a strong product stewardship program to manage those.

As a way of comparison, the 8-hr TLV values for the most common components in the most popular competing products are:

The Toxicity of Common Solvents

Chemical	TLV (8 hr TWA in ppm)
Vertrel® XF, the main ingredient in the Vertrel® products and many of the MicroCare cleaning fluids	200*
HCFC-225, blend	50**
HFC-365	1,000
Cyclopentane	600
IPA (Isopropyl Alcohol)	400
Ethanol (The alcohol used in beer and wine)	1,000
Methanol	200
HCFC-141b	500
n-Propyl Bromide (nPB)	10
Perchloroethylene	25
Trichloroethylene (TCE)	50
Methylene Chloride	25

NOTES: * DuPont's Acceptable Exposure Limit. ** Calculated exposure limit based on a 25 ppm (8-hr TWA) limit for HCFC-225ca and a 200 ppm (8-hr TWA) limit for HCFC-225cb.

To ensure worker safety and the cost-effective use of the solvent, MicroCare has established the industry's leading Product Stewardship Program for solvents. This program is offered free to all customers.

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Understanding the Bromothane^™ Toxicity Rating

Some customers have questions about the toxicity of nPB solvents, specifically the very conservative threshold limit value of 10 ppm established for the Bromothane^™ solvents.

In order to maximize worker safety, early in 2005 and after years of research and deliberations, the American Conference of Industrial Hygienists (ACGIH) finally finalized and established a "Threshold Limit Value" (TLV) of 10 parts-per-million for an eight-hour time-weighted workday. This TLV applies to the "Bromothane^™" brand solvents sold by MicroCare and to all other versions on nPB marketed by other companies under their own brand names.

The TLV values established by the ACGIH have long been recognized as the "gold standard" to which most health professionals reference when looking for guidance on exposure limits. The establishment of a new TLV is a lengthy, open, peer-reviewed process. Persons having views contrary to the proposed ratings are given years to provide new information or other data that is persuasive enough to change the proposed standard. Apparently nobody had enough convincing evidence to cause the TLV committee to move from their 10 ppm recommendation.

According to the ACGIH web site, "The American Conference of Governmental Industrial Hygienists (ACGIH^®) is a member-based organization and community of professionals that advances worker health and safety through education and the development and dissemination of scientific and technical knowledge...For over 60 years, ACGIH^® has been respected for its dedication to the industrial hygiene and occupational health and safety industries. [ The ACGIH mission is ] to provide essential, cutting edge information to government, academia, and corporate facilities throughout America, Canada and countries abroad."

The decision to set the TLV of nPB at 10 ppm was not without controversy. For example, MicroCare and Chemtura have asserted for years the proper TLV should be 10 ppm. But other companies had urged higher threshold levels, as high as several hundred ppm, and the ACGIH chose to disagree with those ratings.

In fact, one trade association went to court in an attempt to block the publication of the ACGIH standard. In a Nov. 30, 2004 press release, the ACGIH noted that the case involved ACGIH's proposed toxicity ratings on n-Propyl Bromide. But the court found the lawsuit was without merit. The chairman of ACGIH's board, Vickie L. Wells, MS, CIH, CSP, stated, "We stand by our [ACGIH's] policies, procedures and processes. We stand by our recommended Threshold Limit Values, and the fairness and thoroughness of the system used in their development and dissemination."

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Storage and Handling of MicroCare Cleaners

The MicroCare cleaners are shipped in drums that can weigh in excess of 600 lb./280 kilos. Moving such heavy objects is a serious undertaking and not to be attempted without the proper equipment, training and supervision. Whenever drums are handled, several cautions should be observed:

Full drums can be moved by forklift trucks and lifted onto racks to provide gravity feed to the point of use.

Drum pumps are strongly recommended.

Always store drums and pails in cold, dry locations out of direct sunlight. Inside storage is greatly preferred over storing the drums outside, where the drums may be vulnerable to the elements. Do not let the temperatures of the drum climb above 50° C/110° F.

Drums should be stored with the bung tightened to eliminate the possibility of spills through a loose or a leaky bung.

Wear the proper safety equipment, including gloves, splash goggles, aprons (when handling open drums), and safety shoes with steel toes if the drums are to be moved.

Before moving drums, make sure the bungs are tightly closed to prevent splashing.

When working near other drums and equipment, be careful of pinch points.

Remember that solvent vapors are heavier than air and will collect in low points and poorly ventilated rooms. Prior to entering a confined space, open all hatches or vents on the equipment and ventilate the area. Review other FAQs for further instructions about working in poorly-ventilated spaces.

Persons moving and storing solvent drums should receive safety training about solvents. They should know where MSDS sheets are stored, the phone numbers to call in case of a spill, and reasonable "first-response" emergency procedures.

Another important thought: while the MicroCare cleaners are extremely cost-effective, they are not cheap. When storing the drums, always double-check that the bungs are tightly sealed. This will minimize evaporation losses and save money.

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