1、FOREWORDIn 1994,the Plumbing and Drainage Institute agreed to work with the American Societyof Mechanical Engineers for the development of this Standard.This Standard includes criteriafor testing and rating of grease interceptors;general requirements for these appurtenances;andan appendix of valuabl
2、e sizing,installation,and maintenance data.The Plumbing and Drainage Institute has a membership of organizations that manufactureproducts for the plumbing industry.The basic aim of PDI is to contribute its combinedtalents and resources to the advancement of plumbing engineering and the plumbing indu
3、stry.This Standard was developed with the assistance of the Plumbing and Drainage Institute.For more than a century,grease interceptors have been used in plumbing wastewatersystems to permit free flow of drainage from sinks and similar equipment and to preventgrease accumulations from clogging conne
4、cting piping and sewer lines.In 1883,one NathanielT.Whiting of California applied for a patent on a grease trap,which was issued in October1884.Whitings design principle does not differ greatly from present-day grease interceptors.For the next 50 years,there was no coordinated effort to standardize
5、ratings or toestablish performance requirements for grease interceptors.Ratings were determined by eachmanufacturer for its interceptors,which were produced in a variety of sizes and types inan effort to meet engineersspecifications and satisfy code requirements.In late 1940 and early 1941,prior to
6、the United Statesentry into World War II,greaseinterceptors were specified for Army posts to meet specifications of the Construction Division,Office of the Quartermaster General.These specifications called for interceptors,whichproved inadequate;it immediately became apparent that a comprehensive en
7、gineering andtesting program was needed to properly rate grease interceptors.Apart from prevention ofsewage systems clogging,properly rated and sized grease interceptors were essential to therecovery of oils and grease so badly needed for the war effort.As a result,a series ofconferences involving t
8、he Research Committee of the Plumbing and Drainage ManufacturersAssociation(now Plumbing and Drainage Institute).representatives of the QuartermasterGeneral,Surgeon General,Army Corps of Engineers,and others was held to develop atesting program to establish flow rates and grease holding capacity for
9、 uniform rating ofgrease interceptors manufactured at that time.The program that emerged from these conferences included exhaustive laboratory testingof each grease interceptor at the lowa Institute of Hydraulic Research at lowa StateUniversity.This phase of the program was covered in a comprehensiv
10、e report issued inAugust 1945.Using the guidelines established in lowa,the Research Committee continuedthe testing program at the United States Testing Company,Inc.,which culminated in thepublication of Standard PDI-G101 in 1949 and the rating of applicable grease interceptors.Since its initial publ
11、ication,Standard PDI-G101 has been widely accepted and is referencedin most plumbing codes.It has been reprinted in its original format many times.The Plumbing and Drainage Institute currently maintains a grease interceptor testing,rating,and certification facility.The scope of this Standard is limi
12、ted to units of 100 gallons per minute(gpm)or lessin rated capacity.Units over the 100 gpm value shall be engineered for the demand ratedfows of the jobsite requirements and specifications.道No roproduction or notworking permitled without liconso from IHSNot for RosaleThe Committee recognizes that a
13、number of sewage treatment communities and otherjurisdictions have established various maximum limits of fats,oils,and greases(FOG)inthe waste stream.The most common of these is 100 mg/L or 100 ppm.The Committeedecided that until a specific maximum limit is universally accepted,no number should bein
14、cluded in the Standard.The inclusion of a maximum limit will be reconsidered foradoption in a future edition of this Standard.Suggestions for the improvement of this Standard are welcome.They should be sent toThe American Society of Mechanical Engineers;Attn:Secretary,A112 Main Committee;Three Park Avenue;New York,NY 10016-5990.This Standard was approved as an American National Standard on November 1,2000.ivNo roproduction or notworking permitled without liconso from IHSNot for Rosale
