Health, safety, and ecological implications of using biobased floor-stripping products.

Introduction

There is an ongoing debate about whether biologically based (biobased), or green, cleaning products are safer, healthier, and more environmentally sustainable than conventional solvent-based cleaners (Committee on Biological Products, Board on Biology, Commission on Life Sciences, & National Research Council, 2000; Mary, 2003; Singh, Ekanem, Wakefield, & Comer, 2003). There are, however, no known detailed studies on biobased floor strippers to support the arguments.

Even if the arguments for biobased products are true, many issues could still confront organizations intending to switch from current petroleum-solvent based products to biobased, or greener, floor-stripping alternatives. One problem is the large number of these products in the market. Literally hundreds of biobased and green product formulations are on the market today Another challenge is that some manufacturers have labeled their products as environmentally friendly, or green, when the products do not objectively offer such attributes (Mitchell, 2000). A third challenge is the existence of great variability in the literature from one vendor or product to another with respect to the performance of biobased products (Marshall, 2005). The fourth and most important challenge, from the EHS perspective, is a lack of detailed eco-toxicological information on the products. For various reasons, including reasons of proprietary information and confidentiality, manufacturers do not disclose all the components of their formulations on the material safety data sheets (MSDSs). This situation makes it extremely difficult to evaluate the toxicity of such products.

A strategy called toxics use reduction (TUR) planning can address some of these problems. TUR planning promotes the use of techniques such as product or material substitution, process changes, and good housekeeping. The main focus is to reduce pollution and human health impacts at the "beginning of the pipe" rather than at the "end of the pipe." TUR planning offers an assessment framework that is often used by toxic use reduction advocates in the state of Massachusetts. The framework was developed under the Massachusetts Toxics Use Reduction Act of 1989. TUR planning often precedes organizational decisions to switch from one toxic product or process to another that is safer, healthier, and more ecologically friendly. The planning tool focuses on pertinent issues such as environmental health and safety (EHS) and economic and other social impacts of processes, products, or services. It is often used in the identification and analysis of available alternative options. The final alternative product, process, or service is then recommended to top management as the optimum one in terms of the attributes used in the analysis (Thomas, Laplante, & Buckley, 1997).

In TUR planning, it would be uneconomical to perform a detailed EHS analysis or even to attempt an economic evaluation of several products, processes, or services. As a result, quick methods of narrowing down the available options have evolved. One of these methods is the use of five key parameters for initial screening of cleaning products.

While products recommended under the TUR planning process for a detailed analysis must be safer and less toxic for workers and other users, they should also be more ecologically friendly than the products they are intended to replace. Evaluating these attributes from the beginning, when biobased products are emerging as "new breeds" of products from biomass feedstocks, is an important step. Early evaluation has the potential to prevent repetition of mistakes made in the past, when generations of products have come and gone out of the market because of EHS or similar problems. As an old saying goes, we should not run to solutions thinking we are "escaping the goblins only to be captured by wolves" (Goklany, 2001). Under the TUR framework, products that seem to perform well technically in terms of the EHS attributes used in the study reported here must also be as cost-effective as the traditional product to ensure easy adoptability and adaptability.

The study examined the EHS implications of some alternative cleaning products made of biologically based (biobased) materials, which are potential substitutes for petroleum-based floor strippers such as Johnson Wax Professional (Pro Strip). The study also attempts to compare the costs of switching to these alternative substitutes, both at full strength and at the dilution ratio recommended by the manufacturers.

Before describing the methods used in the study and the results obtained, this paper will look at some key policy drivers in the promotion of biobased products in the United States.

Drivers for the Promotion of Biobased Products in the United States

Many policies and regulations have evolved to promote biobased cleaning products. One of these policies is the Presidential Executive Order (EO) 13101, Greening the Government Through Waste Prevention, Recycling and Federal Acquisition (Office of the Federal Environmental Executive, 1998). It was signed on September 14, 1998. Section 504 of this EO, together with the guidelines for its implementation (Office of the Federal Environmental Executive, 2001), encourages all federal agencies to purchase environmentally friendly, or greener, products--in particular, products of biobased origin. The EO defines environmentally preferred purchasing as "a purchase of products or services that have a lesser or reduced effect on human health and the environment when compared with competing products or services that serve the same purpose."

Another driver for the promotion of biobased and green janitorial products is Presidential EO 13134, which was signed in August 1999. This EO emphasizes the need for governmental agencies to promote biobased products and bio-energy through the purchases they make.

Similar policy and regulatory initiatives promoting biobased janitorial products have evolved in federal and state government agencies. These government interventions take the form of policies and regulations. Some policies and programs have set up strict environmental criteria for the acquisition of products by government agencies and institutions through environmentally preferable purchasing programs (EPPPs) for janitorial products such as floor strippers (Commonwealth of Massachusetts, 2003; Massachusetts Department of Environmental Protection, 2003; U.S. Environmental Protection Agency, 1998). Since government spending can influence mass consumption of products and services, this policy approach is a step toward recognition of a role for biobased products in U.S. society.

At the federal level, perhaps the largest policy driver for promotion of greener janitorial products of biobased origin is the Farm Security and Rural Investment Act, known more simply as the 2002 Farm Bill (U.S. Department of Agriculture [USDA], 2002). Section 9002 of this law establishes a purchasing program for biobased products; Section 9002 (l)(a) mandates that federal agencies promote biobased products in any purchases that exceed $10,000, and section 9002 (1)(c) requires that the products purchased have the "highest percentage of biobased contents practicable."

Examples of state policies and regulations include Massachusetts Bill 694, or the Healthy Cleaning Act, and the Massachusetts Environmental Purchasing Program (Commonwealth of Massachusetts, 2003, 2005). The essence of the Healthy Cleaning Act is its goal of reducing the use of solvent-based cleaning products in public buildings (i.e., schools, hospitals, daycare centers, and health care centers) in order to reduce asthma and other health threats. According to official records, federal, state, and local government departments combined make purchases of over a trillion dollars a year in goods and services. The Commonwealth of Massachusetts alone, for example, makes purchases of commodities worth about $300 million a year, out of which a significant amount of the money is spent on janitorial products (Green Seal, 2004; Tetra Tech EM, Inc., 1999; Yoder & Thompson, 2003).

Another example of a state law that promotes biobased products as substitutes for traditional ones is the Massachusetts Toxics Use Reduction Act of 1989 (TURA). TURA does not require Massachusetts facilities to implement toxic use reduction projects, nor does it require that facilities meet specific toxic use reduction goals. Instead, it establishes a framework by which businesses can analyze their operations in order to uncover opportunities for toxic use reduction, which may include, but are not necessarily limited to product substitution. The premise is that such opportunities, if implemented, will reduce risks to the environment and health and safety hazards to human beings.

Another significant driver for promotion of green and biobased products is corporate social responsibility The prospect of obtaining a competitive advantage can prompt consumers or producers to switch from a more toxic product to one that is less toxic. Thus, corporations and individuals often choose to move toward sustainability by switching to safer, healthier, and more ecologically friendly products, services, and processes. These changes may in the end also yield champions of environmental and occupational health and safety and improve the corporate image in society. While in many cases this tactic is used to control a competitive edge in the market (Huhtala, 2002), some organizations can be really committed to effecting product substitution if they recognize that their corporate responsibility is as important as their products. Consumers, for instance, may want products that satisfy expectations with respect to EHS and technical performance and at the same time save money (Toxics Use Reduction Institute, 2004).

Confronted with all these issues how can consumers avoid the uncertainties of the past in making their decisions? In the past, a product might come into the market and perform well technically, but perform poorly in terms of environment, health, and safety And after a short period, such product would be banned, or the amount that could be used, disposed of, or emitted in the work environment would be regulated. An enormous number of lessons arise from the many petroleum-based products that were produced and later found to have had significant impacts on the environment, health, and safety of consumers (Leblanc, 1997). Despite these obvious risks, consumers do not take past lessons seriously when they make product selections.

Because of increasing awareness about the EHS impacts of chemicals, however, some consumers now want to make informed decisions about the products they use. In choosing products with minimal or no EHS impacts, consumers, like many responsible producers, can contribute to a sustainable economy for present and future generations. In the end, consumers can reduce insurance costs and long-term liability associated with the use of new and potentially safer products. To make informed decisions and select safer and healthier products, one should subject alternative products to a more detailed life cycle risk assessment or other analytical frameworks (Kolluru, 1996; Raffensperger & Tickner, 1999; Tickner, 2002). These methods are, however, costly and time consuming.

Frameworks for Alternative Assessment of Products

New products, such as biobased floor strippers and the processes that make them, should be subjected to third-party independent investigators for technical and EHS appraisal. Some scientists use the life-assessment-studies (cradle-to-grave) approach to determine the "best" alternatives for a particular application or operation. Life cycle assessment studies, however, can be complex, and subjectivity exists in the data. Other frameworks, such as risk assessments, are also subjective, time consuming, and potentially expensive.

TURI has developed an assessment framework called Pollution Prevention Options Analysis (P2OAsys). This tool can systematically analyze products, processes, and services to determine potential EHS impacts (Toxics Use Reduction Institute, 2005). It requires expertise in collecting and interpreting data from the MSDSs and from databases such as Toxnet.

Because of the difficult procedures that consumers have to go through in deciding on the alternatives for operations, they often resort to a quick cost-benefit analysis, which may consider only costs of purchasing the product and changing equipment. This kind of analysis excludes externalities. An externality is a cost or benefit, incurred by society, that is not part of the production process. Externalities include EHS impacts. In other words, the decision creates costs or benefits to stakeholders other than those making the decision (Tietenberg, 1984).

The method presented below avoids these problems by presenting an alternative assessment framework for screening products faster. This method employs a simple set of key criteria to evaluate the EHS performance of potential biobased floor-stripping products. The rationale is to avoid potentially large costs by subjecting many products to a detailed economic, social, and environmental analysis, as required under the TUR planning strategy.

Materials and Methods

The investigation reported in this paper is part of a larger study that was conducted at the Surface Solution Laboratory (SSL) of the Toxic Use Reduction Institute (TURI) to identify and evaluate safer, greener, and technically viable alternative cleaning products suitable for floor stripping at a hospital facility in Massachusetts. The cost per gallon for each product was determined for use at full strength and at a diluted ratio recommended by the manufacturer (25 percent volume/volume [v/v]).

Selection of the Biobased Products for EHS Assessment

An SSL database (www.cleanersolutions.org) of over 500 products was used to select products for technical-performance tests, the results of which are not reported in this paper. Products that had previously performed well technically were selected and assigned points for five SSL screening criteria (described in the section below). The points were then totaled to give an EHS score. The minimum and maximum points for each criterion were 0 and 10, respectively. Ten points was considered best. Any product that received 0 points for any of the screening criteria was deemed unacceptable and unsuitable for further evaluation.

EHS Implications of Using Selected Biobased Products

Five criteria were used to screen products for EHS. The rationale for using these criteria is that they have been used by SSL and have proved to be useful for quick screening of many alternative surface-cleaning products. These criteria are global-warming potential (GWP); ozone depletion potential (ODP); volatile organic compounds (VOCs); pH; and ratings of the National Fire Protection Association (NFPA) and the Hazardous Material Information System (HMIS) on flammability, reactivity, and health. GWP is a measure of how much a given mass of greenhouse gas is estimated to contribute to global warming--in other words, the ability of the gas to trap heat in the atmosphere. It compares the heat-trapping potential of the gas in question to that of the same mass of carbon dioxide (C[O.sub.2]), whose GWP is 1 (Table 1). The units of measure are the absorbing capability of the gas relative to C[O.sub.2] and the decay rate of each gas relative to C[O.sub.2]. Ozone depletion potential (ODP) (Table 2) refers to the capability of a chemical to destroy an ozone layer that keeps ultraviolet and other harmful radiation emitted by the sun from reaching the earth's surface. VOCs are petroleum-based chemicals that off-gas from many products and can cause significant safety, health, and ecological impacts (Table 3). The pH criterion provides a measure on a scale of 0 to 14 of the acidity or alkalinity of a solution (Table 4). Usually a pH of 7 is a neutral position on this scale, and any number lower or greater than 7 indicates acidic or alkaline media, respectively. Finally, the National Fire Protection Association (NFPA) and the Hazardous Material Information System (HMIS) have both developed ratings that evaluate the health hazards, flammability, reactivity, and physical hazards of chemicals and products as a means of communicating those hazards to consumers (Table 5).

It is important to recognize that the five parameters used in the study are not the only criteria available for evaluating EHS impacts of chemicals and products. They have strengths and limitations, which are not discussed in this article. As a result, other organizations may be compelled to use other systems of assessment. Such systems may include toxicological assessment procedures that are specific to products being assessed, such as Green Seal and Canadian Environmental Choice Program standards. The choice of which health hazard or environmental hazard assessment will be documented therefore depends on the categories of hazards one wishes to investigate and document.

An MSDS for each biobased product was used to obtain parameters such as density or specific gravity (sg). For example, the VOC composition of the product was multiplied by its specific gravity, also specified on the MSDSs, to give scores for VOCs (mg/L). Similarly, the MSDSs were used to gather data on the other parameters: pH; GWP; ODP; and the HMIS/NFPA categories of health, flammability, and reactivity. The ratings that nine acceptable products received for these parameters are shown in Table 6, along with the total SSL scores those products received. Table 7 shows the SSL points each product was assigned for the screening parameters.

As described above, the SSL points for the five parameters were added to give a total EHS-screening score for each product (Table 6, Table 8). The maximum possible EHS-screening score would be 50; this number represents the sum of the points assigned for the each of the five parameters.

It should be noted that the five parameters were used only for a quick screening of cleaning products and that no claim is made about their applicability to the entire range of biobased chemical products and composite materials. Different or additional parameters, such as persistence, bioaccumulation and aquatic-toxicity potential, carcinogenicity, mutagenicity, and reproductive toxicity (CMR), may be needed for detailed analysis. Furthermore, it is now apparent that the parameters used for a quick EHS analysis of the floor strippers may not necessarily be the parameters that should be used for all the other biobased product and chemical categories.

Cost-Benefit Analysis

The cost for each product was determined on the basis of the dilution ratio recommended by the manufacturers. To do so, the authors compared the cost of the "best" alternative at 25 percent v/v and at full strength with the currently used product at these concentrations.

Results and Discussion

EHS Scores of the Products Tested

All of the eight biobased products that were examined had EHS scores higher than 26 (Table 6), which was the score for the currently used product (Pro Strip), according to the SSL criteria used in the study. These results imply that all of these products are at least potentially better than the traditional product with respect to the parameters used. Botanic Gold had the highest EHS-screening score, a score of 49, followed by SoySolv 11, EnviroStar Green Floor Stripper, and DBE-6, which had scores of 48, 40, and 38, respectively. SolSafe 245, Bio-T-Max, SoySolv 11 Plus, and CornSolv all scored 37. Most of the petroleum-solvent-based cleaning products that are being replaced at SSL received a score of 37. Thus, any product that earns a score above 37 should be considered safer, healthier, and more ecologically friendly than most conventional petroleum-based products.

Cost Comparison

At 25 percent v/v, Johnson Wax Professional (Pro Strip) was found to be the cheapest product to use, costing $9.90 per U.S. gallon ($2.62 per liter). These costs are shown in Figure 1. According to the MSDS, Pro Strip contains sodium xylene sulfonate, benzyl alcohol, and 2-butoxyethanol, or ethylene glycol monobutylether (EGBE). An eco-toxicological review has linked these components to significant negative health, safety, and environmental impacts (Massawe, 2005). Because of time constraints, these indirect but important costs could not be estimated. The cost for all eight biobased products ranged from $15.50 per gallon ($4.10 per liter) for Eco-Natural Floor Stripper to $59.00 per gallon ($15.61 per liter) for Botanic Gold. These figures represent cost at full strength per gallon (3.78 liters).

Pro Strip has many technical advantages, including high contaminant removal efficiency (Massawe, 2005). Use of this product shortens the time needed to strip the floor in comparison with the biobased floor strippers, which require a longer time and heating. The costs of heating may offset potential EHS benefits. If these products are to be promoted, this issue and others may require further investigation.

Conclusion and Recommendations

With an initial EHS screening score of 49, Botanic Gold seems to have outperformed Pro Strip with respect to the criteria used in the study reported here. SoySolv 11 and Green Floor Stripper had scores of 48 and 40, respectively. Botanic Gold, SoySolv 11, and Green Floor Stripper each had a screening score approximately twice that of Pro Strip, which had a score of about 26. This result indicates that they could be safer, healthier, and more ecologically friendly with respect to the criteria used in the study. All the other potential biobased floor strippers reviewed in the study had initial screening scores above 37 but below 40.

These results indicate that biobased cleaning products capable of floor stripping are better than the currently used solvent-based product. Botanic Gold was best with respect to the five EHS parameters used in the study.

An evaluation of the costs of the products showed that the costs of biobased floor strippers at their full strength ranged from a minimum of $15.50 per gallon ($4.10 per liter) for Eco Natural Floor Stripper (WPR) to about $59.00 per U.S. gallon ($15.61 per liter) for Botanic Gold. At 25 percent volume by volume (v/v), the recommended dilution ratio for the current product, the cost of the Botanic Gold is $14.75 per gallon ($3.90 per liter), about five times that of Pro Strip, which is $2.48 per gallon ($0.65 per liter). It should be noted that these costs do not reflect all the EHS costs, such as disposal, recycling fees, and social costs such as impacts of fertilizers and genetic modification of crops used as feedstocks for nonfood manufacturing. Therefore, it is most likely that Botanic Gold will be cost-effective and may contribute to EHS sustainability in the long run.

The authors conclude that Botanic Gold can be used as an alternative to Pro Strip because its EHS screening scores indicate that it is potentially safer with respect to the parameters studied. The techniques used in the study can serve to compare and quickly perform initial screening of biobased products, particularly cleaning products.

It cannot be concluded from these results alone that all biobased products are safer with respect to EHS, because the information and the number of products evaluated were limited. The evaluation method was also limited in scope, as it attempts to evaluate cleaning products only.

The authors recommend that a detailed EHS analysis based on sophisticated tools such as TURI's P2OAsys or other available assessment frameworks be conducted on Botanic Gold. It is also recommended that large field trials be conducted and janitors' or consumers' perceptions be assessed. A detailed analysis of the eco-toxicological properties of biobased floor strippers would also investigate the common additives in the Botanic Gold formulations and assess these additives through use of World Wide Web databases such as Toxnet. Finally, a review of current and relevant policies that can promote biobased products should be carried out in order to encourage a broader public debate about the future of the biobased industry in the context of sustainability.

[FIGURE 1 OMITTED]

Acknowledgement: The authors acknowledge the financial support of the Toxics Use Reduction Institute (TURI) for their study. They also express sincere gratitude to Carole LeBlanc, TURI SSL laboratory director, for her technical support during the design and execution of the study. Without the support of all the firms that provided samples of floor strippers for testing in the laboratory, the study would not have been possible. The authors also appreciate the input of Professor Margaret Quinn and Maria Brunette during the set up and execution of the experiments.

Disclaimer: The authors are not directly or indirectly associated with any product or company named in this paper. Mention of a product or company by name is not an endorsement. The authors are not responsible for any injuries or accidents that may occur during use of the products listed in this article.

Corresponding Author: Ephraim Massawe, Research Associate in Cleaner Production/Industrial Hygiene, University of Massachusetts Lowell, One University Avenue, Kitson Hall, KT 200, Lowell, MA 01854. E-mail: [e-mail].

REFERENCES

Committee on Biological Products, Board on Biology, Commission on Life Sciences, & National Research Council. (2000). Biobased industrial products: Priorities for research and commercialization. Washington, DC: National Academy Press.

Commonwealth of Massachusetts. (2003). Health Cleaning Products Act. Senate Bill No. 694. Retrieved May 05, 2005, from http://www.cleaningpro.com/page.cfm.

Commonwealth of Massachusetts. (2005). Procurement regulations, policies and programs. Environmentally Preferable Products (EPP) Procurement Program. Retrieved December 2, 2005, from http://www.mass.gov/epp/regs.htm.

Goklany, M.I. (2001). The precautionary principle: A critical appraisal of environmental risk assessment. Washington, DC: Cato Institute.

Green Seal. (2004). Floor-care products: Finishes and strippers (Green Seal's Choose Green Reports). Retrieved November 20, 2005, from http://www.greenseal.org/.

Huhtala, A. (2002, May). Strategies and mechanisms to promote cleaner production financing. Paper presented at the NATO/CCMS Conference on Industrial Ecology, Vilnius, Lithuania. Retrieved May 15, 2005, from http://www.epa.gov/ord/NRMRL/pubs/625r03006/PowerPoint/IE4.ppt.

Kolluru, R.V (1996). Risk assessment for environmental health and safety professionals. New York: McGraw Hill.

LeBlanc, C. (1997, May). The evolution of cleaning solvents. A close look into the basics of solvents and surface cleaning. Precision Cleaning Magazine, pp. 11-16.

Marshall, J. (2004, August). Greening of cleaning: Renewable feedstock alternatives in surface cleaning bio-based alternative solvents--How well do they work. Proceedings of the 3rd Annual International Surface Engineering Congress and Exhibition, Orlando, FL.

Mary, A.C. (2003). Do bio-based products move us toward sustainability? A look at three USEPA case studies. Environmental Progress, 22, 277-292.

Massachusetts Department of Environmental Protection. (2003). Program assessment for the Commonwealth of Massachusetts Environmentally Preferred Procurement Program: A report submitted by North Eastern Recycling, Inc. Retrieved October 30, 2005, from http://www.mass.gov/epp/info/finalreportdec02.doc.

Massawe, E. (2005). Performance characterization of biobased cleaners: A focus on the floor stripping products. Unpublished study conducted for partial fulfillment of M.Sc. degree, University of Massachusetts Lowell.

Mitchell, S. (2000). Mr. Green takes on Mr. Clean. Carbohydrate Economy, 2 (4). Retrieved May 25, 2005, from http://www.carbohydrateeconomy.org/library/admin/uploadedfiles/Mr_Green_Takes_On_Mr_Clean.htm.

Office of the Federal Environmental Executive. (1998). Executive order no. 13101: Greening the government through waste prevention, recycling and federal acquisition. Retrieved November 25, 2005, from http://www.ofee.gov/eo/13101.htm.

Office of the Federal Environmental Executive. (2001). Greening the government: A guide to implementing executive order no. 13101. Retrieved October 30, 2005, from http://www.ofee.gov/eo/greening.pdf.

Raffensperger, C., & Tickner, J.A. (Eds.). (1999). Protecting public health and the environment: Implementing the precautionary principle. New York: Island Press.

Singh, S.P., Ekanem, E., Wakefield, T., & Comer, S. (2003, June). Emerging importance of biobased and bio-energy in the US economy: Information dissemination and training of students. Paper presented at the World Food and Agribusiness Symposium and Forum, Cancun, Mexico.

Tetra Tech EM, Inc. (1999). Final report: Aqueous Cleaning Demonstration Project. San Francisco: City and County of San Francisco, Hazardous Waste Management Program Administrative Service Department.

Thomas, K., Laplante, J., & Buckley, A. (1997). Guidebook of part cleaning alternatives. Retrieved February 13, 2007, from http://www.resourcesaver.org/file/toolmanager/016F6185.pdf.

Tickner, J.A. (2002). Developing scientific and policy methods that support precautionary action in the face of uncertainty--The Institute of Medicine on Agent Orange. Public Health Reports, 117, 534-545.

Tietenberg, T. (1984). Environmental and natural resources economics (pp. 45-46). London: Scott, Foresman, and Company.

Toxics Use Reduction Institute. (2004). Toxics use reduction planner course. Lowell, MA: University of Massachusetts Lowell.

Toxics Use Reduction Institute. (2005). Pollution prevention option analysis (P20asys) tool to compare materials. Retrieved June 20, 2005, from http://www.turi.org/content/content/view/full/1125/.

U.S. Department of Agriculture. (2002). Farm Security and Rural Investment Act of 2002. Retrieved August 30, 2005, from http://www.nrcs.usda.gov/about/legislative/pdf/PLawl07171.pdf.

U.S. Environmental Protection Agency. (1998). Green spending. A case study of Massachusetts' Environmental Purchasing Program. Retrieved October 30, 2005, from www.epa.gov/opptintr/epp.

Yoder, R., & Thompson, M. (2003, November). Being (and buying) green in today's business world. Training conducted at WasteCap's Business R & R Event: Reduction & Recycling, Lincoln, NE.

Ephraim Massawe, M.S., Sc.D.

Kenneth Geiser, M.C.P., Ph.D.

Michael Ellenbecker, M.S., Sc.D.

Jason Marshall, M.S.

TABLE 1 The SSL Global-Warming Potential (GWP) Criterion

Score                 SSL Points

GWP = 0               10
GWP = 1 (C[O.sub.2])   5
All others scores      0

TABLE 2 The Ozone Depletion Potential (ODP) Criterion

ODP Rating         SSL Points

0                  10
All others scores   0

TABLE 3 The Volatile-Organic-Compound (VOC) Criterion

VOC Content Rating (g/L)  SSL Points

0-24                      10
25-49                      9
50-74                      8
75-99                      6
100-149                    5
150-199                    4
200-299                    3
300                        2
>300                       0

TABLE 4 The pH Criterion

pH Level   SSL Points

 0-1.0      0
 1.1-2.4    4
 2.5-2.9    6
 3.0-4.0    7
 4.1-5.9    8
 6.0-6.9    9
 7.0-7.9   10
 8.0-8.9    9
 9.0-9.9    8
10-11.4     7
11.5-11.9   6
12-12.4     4
12.5-12.9   2
13-14       0

TABLE 5 The Hazardous Material Classification System (HMIS) and National
Fire Protection Association (NFPA) Rating Criterion, as Applied to 13
Products* in Initial Screening

         HMIS/NFPA
Product  Rating**   SSL Points***  Remarks

 1       0          10
 2       1           9
 3       2           8
 4       3           7
 5       3           2             The SSL score was lowered because the
                                   product received a rating of 3 for
                                   either flammability, reactivity, or
                                   health. ([dagger])
 6       4           6
 7       4           1             The SSL score was lowered because the
                                   product received a rating of 3 for
                                   either flammability, reactivity, or
                                   health. ([dagger])
 8       5           5
 9       5           0             The SSL score was lowered because the
                                   product received a rating of 3 for
                                   either flammability, reactivity, or
                                   health. ([dagger])
10       6           4
11       7           0
12       8           0
13       9           0

* Any product that received 0 points for any of the screening criteria
was deemed unacceptable and unsuitable for further evaluation.
** On this scale, lower values are considered better. The authors
obtained the HMIS/NFPA rating by totaling individual ratings for three
HMIS/NFPA hazard categories: flammability, reactivity, and health. No
product on the market may have a rating of >3 for any one of these three
categories.
*** On this scale, higher values are considered better. To compute the
SSL points, the authors subtracted the NMIS/NFPA rating from the maximum
possible number of SSL points, which is 10. Thus, the lower the total
HMIS/NFPA rating is, the higher the SSL points are.
([dagger]) An NFPA/HMIS rating of 3 for flammability, reactivity, or
health suggests the presence of a substantial hazard. (Manufacturers may
recommend special handling procedures, including use of personal
protective equipment or respirators.) Because it is the goal of SSL not
to promote the use of hazardous materials, this scoring system lowers
the SSL points for any product that has been assigned an HMIS/NFPA
rating of 3 for either flammability, reactivity, or health.

TABLE 6 EHS Criteria Ratings for Nine Products Examined in the Prefield
Trials, with Total SSL Scores

                                                HMIS      HMIS
              Product          VOC              (Health)  (Flammability)
Type          Name             (g/L)  GWP  ODP  (0-4)     (0-4)

Biobased      Botanic Gold         0  0    0    0         0
              Solsafe 245        850  0    0    2         1
              Bio T Max          780  0    0    0         2
              DBE 6            1,050  0    0    1         1
              Soysolv II           0  0    0    1         0
              Soysolv II Plus    520  0    0    1         2
              Corn Solv        1,035  0    0    1         2
Non-biobased  Green Floor        159  0    0    1         0
                Stripper
              Pro Strip          505  0    0    3         0

                               HMIS                   SSL
              Product          (Reactivity)  pH       Score
Type          Name             (0-4)         (0-14)   (0-50)

Biobased      Botanic Gold     0             8.8-9.1  49
              Solsafe 245      0             N/A      37
              Bio T Max        0             8        37
              DBE 6            0             N/A      38
              Soysolv II       0             6        48
              Soysolv II Plus  0             6.9      37
              Corn Solv        0             N/A      37
Non-biobased  Green Floor      0             10.5     40
                Stripper
              Pro Strip        0             12.1     26

TABLE 7 SSL Points Assigned to Individual Products, by EHS-Screening
Criterion

Type          Product Name     VOCs (g/L)  GWP  ODP

Biobased      Botanic Gold     10          10   10
              Solsafe 245       0          10   10
              Bio T Max         0          10   10
              DBE 6             0          10   10
              Soysolv II       10          10   10
              Soysolv II Plus   0          10   10
              CornSolv          0          10   10
Non-biobased  Green Floor       4          10   10
                Stripper
              Pro Strip         0          10   10

                               HMIS    HMIS          HMIS
Type          Product Name     Health  Flammability  Reactivity  pH

Biobased      Botanic Gold     0       0             0            9
                               Points for this criterion = 10
              Solsafe 245      2       1             0           10
                               Points for this criterion = 7
              Bio T Max        0       2             0            9
                               Points for this criterion = 8
              DBE 6            1       1             0            9
                               Points for this criterion = 8
              Soysolv II       1       0             0            9
                               Points for this criterion = 9
              Soysolv II Plus  1       2             0            9
                               Points for this criterion = 8
              CornSolv         1       2             0           N/A
                               Points for this criterion = 8
Non-biobased  Green Floor      1       0             0            7
                Strippe        Points for this criterion = 9
              Pro Strip        3       0             0            4
                               Points for this criterion = 2

TABLE 8 Technical-Performance Scores and EHS-Screening Scores for Nine
Products

                                    Technical-
                                    Performance    EHS-
Type          Product               Score          Screening
of Product    Name                  (Qualitative)  Score      Remarks

Biobased      Botanic Gold          55             49          25% (v/v)
              Solsafe 245           50             37         100% (v/v)
              Bio T Max             65             37         100% (v/v)
              DBE 6                 50             38         100% (v/v)
              Soysolv II            **             48         n/a
              Soysolv II Plus       84             37         100% (v/v)
              CornSolv              30             37         Foul smell
Non-biobased  Green Floor Stripper  50             40          25% (v/v)
              Pro Strip             99             26         100% (v/v)