Fowler Associates Labs

First Published in EOS/ESD Technology Feb/March 1988

How to Select Flooring

A systematic analysis to determine the best flooring for you.

Steve Halperin: Halperin & Associates, Elmhurst, IL

Take the first step down the yellow brick road to ESD control by beginning with floor control. You know it is a critical area, but are you handling it correctly? Do you know how to analyze the issue systematically? Follow this survey and learn the whys and whats on flooring that pertain specifically to your business.

Section 1: Background

The first issue to adddress is needs.
1. Why, specifically, does your company need ESD control? Circle all that apply.
a. Required by military contract.
b. Required by commercial customer specifications.
c. We have confirmed ESD losses in our facility.
d. Our customeers have confirmed ESD losses due to our operation.
e. Management insists on an ESD program.
f. We do not have proof of losses, but suspect ESD losses.
g. Other

Next, it is important to understand the elements involved in each different physical area of your company. By addressing an area in terms of size, traffic and sensitivity, you will get a clearer picture of your needs.

What is the approximate total measurement of each area in ft.²?
a. < 1000
b. 1000 to 5000
c. 5001 to 10,000
d. 10,001 to 20,000
e. 20,001 to 30,000
f. 30,001 to 40,000
g. 40,001 to 50,000
h. > 50,000

How many people work in each ESD area?
a. < 5
b. 5 to 10
c. 11 to 20
d. 21 to 50
e. 51 to 75
f. 76 to 100
g. 101 to 200
h. > 200

What is the ESD sensitivity in volts of each area?
a. < 100
b. 101 to 1000
c. 1001 to 2000
d. 2001 to 4000
e. 4001 to 6000
f. 6001 to 8000
g. > 8000
h. We do not know device or product sensitivity.

Area description matrix: For the areas listed on the answer sheet (questions 2-13), use the answers from the questions above and enter the appropriate letter in the corresponding column.

14. Does your plant utilize clean room operations? If it does, what is the clean room classification?
a. Class 1000
b. Class 100
c. Class 10
d. Other

Now the first stage is completed. You know your company's primary ESD-control needs, you know the areas that require control, and you know the sizes and sensitivity of those areas. Take a minute to note the lowest voltage listed in your sensitivity rating. This will provide an indication of your facility's worst-case ESD sensitivity and form a guideline for the degree of control you must establish for the plant in general.

Section II: Present ESD Control

How do you currently control floors in ESD-sensitive areas? By compiling a breakdown of the floor surface and type of ESD floor control in the different areas of your company, you will be able to establish your current status and determine potential modifications that may be necessary. Using the following answer guides, fill out the floor description matrix outlined on the answer sheet (Section II, questions 1-12); enter the appropriate letter in the corresponding column.

What type of floor surface are you using?
a. Cement floor without sealant
b. Cement floor with epoxy sealant
c. Painted cement floor
d. Vinyl tiled floor
e. Wooden floor without varnish
f. Wooden floor with varnish
g. Marble floor
h. Poured terrazzo
i. Carpeted (roll stock; seamed)
j. Carpet tiles
k. Other

What type of ESD floor control do you have?
a. Installed conductive tile
b. Installed conductive sheet goods at workstations and critical equipment
c. Installed static-controlled carpeting (tiles or rolled stock)
d. ESD floor wax
e. Periodic application of topical antistats or floor dressings
f. ESD-controlled mats only
g. ESD-controlled aisle runners
h. Conductive paints or epoxy sealants
i. None presently used
j. Other

Section III: Defining Performance Needs

When selecting any ESD product for a given application, there are four areas of concern: mechanical performance, chemical attributes, electrostatic discharge functions, and value. The following section is oriented toward defining flooring needs as related to these four areas.

Mechanical Considerations

These include such issues as installation, maintenance, traffic, and longevity, which will carry different weights in different companies. The weight that an issue carries depends on various questions. Can the plant be closed for two days in order to install a new ESD floor? A week? Are shiny floors a consideration?

Using the rating scale below, determine the appropriate value for each issue. Enter the budget, time or frequency for each element. This will help further quanify the true impact of each factor.
a. Extremetly important, a top priority in our decisions.
b. Very important to our facility, usually included.
c. A consideration, but not a decision making factor.
d. Not a decision factor at this time, but should be.
e. Not a consideration for flooring in our facility.
f. Not suitable or appropriate for our facility.

Rate the following considerations.

1. Installation concerns:
a. Time allowed
b. Budgeted cost per ft²
c. Prepartation of current floor surface
d. Moisture seepage through cement

2. Maintenance concerns:
a. Desired frequency
b. Budgeted cost per ft²
c. Required equipment
d. Manpower needs
e. Appearance

3. Traffic and use concerns:
a. Foot traffic
b. Cart traffic
c. Material hand truch traffic
d. Lift truck traffic
e. Machine or surface loading

4. Longevity concerns (varies with ownership versus lease of building and maintenance considerations):
a. Life of ESD floor performance
b. Potential for plant remodeling
c. Potential for plant relocating
d. Potential change in ESD needs

In addition to these, there are other mechanical concerns. Is the same floor suitable for all area applications? Will carpeting chosen for the CEO's office be effective in general manufacturing areas? Will the same flooring you choose for your soldering or chemical areas be a success in shipping and receiving? Will high versus low traffic play a part in your decision-making process?

Futher considerations include lease-hold restrictions. Does the owner of the building have restrictions on the type of reconstruction you can do? Is there a policy concernng removal? If so, concrete resurfacing might not be a viable option. What about company policies? Are there rules about appearance or safety?

Chemical Considerations

Chemical attributes can be seen as having a negative or positive influence on the product and the environment. Issues such as outgassing or corrosivity either are a critical area of concern, or they are not.

Determine whether or not each of the following chemical attributes is a factor in your decision-making process for ESD control floor materials.
5. Outgassing
6. Flammability
7. Sloughing
8. Contact contamination
9. Corrosivity
10. Other

Electrostatic Function

The next area to consider in ESD control is electrostatic functions. Traditionally, when you look at an ESD-control material, you look for its ability to dissipate a charge and to define the path a charge takes to ground. When considering floor materials, it is important to determine how much charge is generated and where it goes. How quickly it dissipates may also be a concern in some environments.

Using the questions below determing the appropriate value for each issue listed on teh answer sheet (section III, questions 11-17). Enter comments and specific performance requirements for an element in the area provided.

Rate the suitability of the ESD function for floor control.
A. A consideration, but not a decision-making factor
B. Not a descision making factor at this time, but should be
C. Not a consideration for flooring in our facility
D. Not sutiable or appropriate for our facility

What is your acceptable performance range?
A. Our desired performance range
B. We would accept this performance range
C. We would only accept this range in certain areas
D. We would not accept this performance range

How often do you evaluate or survey floor ESD performance?
a. Daily
b. Weekly
c. Monthly
d. Quarterly
e. Semiannually
f. Annually
g. Never
h. Other

In addition to flooring, footwear must also be an ESD concern. A controlled floor helps to reduce charges on the body, but it can not be totally effective unless controlled footwear is worn. Luckily, today's ESD-controlled footwear do not even resemble bowling shoes. Whether you want wingtips, pumps, or workshoes, there is suitable ESD-controlled footwear available for operations and administrative personnel alike. (For question 18, follow the same proecure described above.)

Defining Value

Only after mechanical, chemical and electrostatic requirements are determined is it time to look at value. First, determine the importance of each factor in the decision making process. (Every installation is differnt, not only physically, but also in terms of need. When considering floor materials, note any custom concerns that are particular to your company.) To determine the value, you must look at the key elements of these considerations, adn then at your budget constraints.

List you most important factor in the following three categories and rank in order of importance.
19. Mechanical
20. Chemical
21. Electrostatic

Determine the maximum allowed cost for the following.
22. Installation per ft²
23. Material per ft<sup>2
24. Maintance per year</sup>

^{A company must define its needs and know the cost factors before it can even consider the products available in the market place. The comparison must be based on rational value analysis, including all mechanical, chemical, and electrostatic factors. You cannot compare a low-cost solution that only meets some of your requirements with a higher-cost flooring material that meets all your needs. Only products meeting the fundamental requirements of a company can be rationally compared.}