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Materials of Construction
National and local codes call for semiconductor manufacturing equipment to be constructed from non-combustible materials. An exception allows alternative materials to be used when there is an issue with chemical compatibility. Due to the fire risks and high combustible loading associated with plastic construction materials like polypropylene, polycarbonate, and PVC that are used extensively in the industry, a number of plastics manufacturers are developing new materials to minimize fire risks. These are known as "Fire Safe" or non-fire propagating materials. Manufacturers are required to have their materials be tested and qualified using one of the two methods listed below:

FM 4910 Test Standard 4910 ­ Cleanroom Material Flammability Test Protocol
UL 2360 Standard Test Method to Determine Combustibility Characteristics of Plastics used in Semiconductor Tool Construction

Many jurisdictions require fire detection and suppression systems on equipment manufactured with combustible plastics. In many cases, authorities are not requiring on-board detection and suppression systems for equipment manufactured with fire safe plastics.

Fire Detection and Suppression
When Fire Safe plastics are not used, many authorities having jurisdiction require on-board fire detection and suppression systems. Fire detection systems vary based on the specific equipment application, with smoke, heat, and flame detectors being the most common detectors used in the industry. There are many choices available as each manufacturer offers units using different methods of detection and different sensitivity ranges. These detection systems can be designed to do multiple functions. In addition to sounding a local alarm, they can be connected to facility alarm systems, interlocked to remove power from the equipment, and/or initiate suppression systems.

There are numerous types of suppression systems available. Many are designed to extinguish a fire in its very early stages to minimize the damage from both the fire itself and the contamination from smoke damage in the facility. These early suppression systems include gaseous agents like Intergen, FM 200, and CO2. Another quick responding system uses Fine Water Mist droplets. Due to the large loss potential associated with contamination from smoke generation internal sprinkler systems are not normally used to control developing fires.

CHANGES IN SEMICONDUCTOR REGULATIONS
Previously there were there three Code development bodies in the United States (U.S.). In general, the family of Codes used was dependent upon what region of the US you resided in as outlined below:

International Conference of Building Officials (ICBO)
          o Region: Primarily used in the Western half of the U.S.
          o Codes Published:
Uniform Building Code
Uniform Fire Code
Uniform Mechanical Code (jointly published with IAPMO)

Building Officials & Code Administrations International, Inc. (BOCA)
          o Region: Primarily used in the Northeastern region of the U.S.
          o Codes Published:
National Building Code
National Energy Conservation Code
National Fire Prevention Code
National Mechanical Code
National Plumbing Code

Southern Building Code Congress International, Inc. (SBCCI)
     o Region: Primarily used in the Southeastern region of the U.S.
     o Code Published:
Standard Building Code
Standard Fire Prevention Code
Standard Gas Code
Standard Mechanical Code
Standard Plumbing Code

International Codes Council
In December 1994, BOCA, ICBO, and SBCCI formed an umbrella organization, known as the International Codes Council (ICC). Their goal was to develop a single set of International Codes to replace each organization's separate codes; the National Codes developed by Building Officials and Code Administrators (BOCA), the Standard Codes developed by the Southern Building Code Congress International (SBCCI), the Uniform Codes developed by the International Conference of Building Officials (ICBO). Originally, plans were for the ICC to partner with the National Fire Protection Association (NFPA) and jointly develop the International Fire Code (IFC), which would work in concert with the International Building Code (IBC). Due primarily to disagreements in Code Development methodology, the NFPA severed its partnership with the ICC and is no longer involved in the ICC Code development process. The 2000 editions of the International Building Code and International Fire Code were developed and released by the ICC In January 2000.

NFPA 1 - Uniform Fire Code
The NFPA has decided to develop its own family of consensus codes. The Western Fire Chiefs (WFCA) has retained the rights to the Uniform Fire Code, and along with the International Association of Plumbing & Mechanical Officials (IAPMO) have partnered with the NFPA to produce a full set of consensus codes for the built environment. The 1997 edition of the UFC is the final version published by ICBO. In 2000, the Western Fire Chiefs published an updated version of the Uniform Fire Code. WFCA, IAPMO, & NFPA will publish NFPA 1 ­ Uniform Fire Code in 2003. The NFPA is also developing The NFPA 5000, Building Code that will be published in August 2002.

NFPA 1 will include various sections previously contained in the ICBO & WFCA versions of the UFC like Article 80 ­ Hazardous Materials. A number of sections in NFPA 1 will direct its user to other existing NFPA Codes and Standards, for example, NFPA 30 for Flammable and Combustible Liquids and NFPA 70 ­ the National Electric Code. For Semiconductor Facilities, users of will be directed to NFPA 318, Standard for the Protection of Cleanrooms. NFPA 318 is currently in a 2-year revision cycle with its next published version expected to be available in August 2002. The 2002 edition will be renamed NFPA 318 ­ Standard for the Protection of Semiconductor Fabrication Facilities and will incorporate the requirements of Article 51 from the ICBO & WFCA versions of the UFC.

State of California Update
In Sacramento on October 25, 2000 - The California Building Standards Commission (CBSC), who are in charge of reviewing, approving, and publishing Building Standards for the State of California, voted 5 to 1 to not use the International Building Code or the International Fire Code. As a part of this vote, the Commission has elected to continue using the 1997 Uniform building Code as the basis for the 2001 California Building Standards Code. The Commission voted to continue with the adoption of the 2000 edition of the UFC developed by the Western Fire Chiefs (WFCA), the 2000 edition of the Uniform Mechanical & Plumbing Codes (UMC & UPC) developed by the International Association of Plumbing & Mechanical Officials, and the 2000 edition of the National Electric Code (NEC) developed by NFPA.

This vote covers the adoption process for the next three years, when the Commission will again meet to determine which family of Codes will be adopted. The Building Standards Commission had previously utilized the 1997 editions of the UFC, UMC, and UPC, and the 1996 edition of the NEC.

SEMI Standards
Semiconductor Equipment Manufacturers International (SEMI ) develops Safety Standards and Guidelines for Semiconductor Manufacturing Equipment. SEMI S2-0200 Environmental, Health, and Safety Guideline for Semiconductor Manufacturing Equipment is one such document. See other sections of the Earth Tech Microelectronics Website for more details associated with this Safety Guideline.

SEMI S14-0200 Safety Guidelines for Fire Risk Assessment and Mitigation for Semiconductor Manufacturing Equipment provides guidelines for completing a Fire Risk Assessment on a piece of equipment used to manufacture, measure, assemble, or test semiconductor products. This guideline evaluates the equipment from the fire risk perspective, looking at combustible fuel loading from materials of construction and potential hazardous process chemistry, various sources of ignition, and the presence of oxidizers that can contribute to the fire risk. Any type of fire mitigation system included with the equipment is evaluated and reported on. The evaluation procedure should include any mitigation techniques available to reduce the risk.