1、 NSF Protocol P335 Hygienic Commercial Hand Dryers April, 2007 April 2007 Copyright 2007 NSF International Page i NSF International, an independent, not-for-profit organization, is dedicated to public health safety and protection of the environment by developing standards, by providing education and
2、 by providing superior third-party conformity assessment services while representing the interest of all stakeholders. This Protocol is subject to revision. Contact NSF to confirm this revision is current. Users of this Protocol may request clarifications and interpretations, or propose revisions by
3、 contacting: NSF International 789 Dixboro Road Ann Arbor, MI 48105 Phone: (734) 769-8010Telex: 753215 NSF INTL FAX: (734)769-0109 E-mail: infonsf.org Web: http:/www.nsf.org April 2007 Copyright 2007 NSF International Page ii NSF Protocol P335 Hygienic Commercial Hand Dryers NSF International Engine
4、ering Bacteria and mold present in the retained water is removed or killed before discharge; No objectionable odors shall be detected from the air. 4.4 Product literature Each system shall be accompanied by a comprehensive manual. This may consist of separate documents covering each of the following
5、 sections or may be combined into a single manual with subsections. 4.4.1 Owners manual: The manual or section intended for owner reference shall be written so as to be easily understood by the intended reader and shall include, at a minimum: Model designation; A statement confirming that the system
6、 meets the requirements of NSF Protocol for Hygienic Commercial Hand Dryers; A functional description of system operation, including diagrams illustrating basic system design; A clear statement of the types of environment in which the system may be installed; A list of substances (including cleaners
7、) that, if placed in the system, may adversely affect the system or process; Operating instructions that clearly describe proper function of the system and the operating and maintenance responsibilities of the owner and authorized service personnel; A designation of the length of one operating cycle
8、, if the operating cycle is preset; Clear methods and criteria to be used to identify system malfunctions or problems; A statement instructing the owner to reference the system data plate in the event that a problem arises or service is required; Name and telephone number of an appropriate service r
9、epresentative to be contacted in the event that a problem with the system occurs; Electrical schematics for the system if not appearing on the system itself. 4.4.2 Installation, operation, maintenance, and troubleshooting manual: The manual or sections intended for distribution to authorized represe
10、ntatives shall be written so as to be easily understood by the intended reader and shall include, at a minimum: A numbered list of system components and an accompanying illustration, photograph, or print in which the components are respectively identified; Basic design, construction, and material sp
11、ecifications, for the systems components; Wiring schematics for the systems electrical components; Unpacking instructions including safety considerations, identification of fragile components, and measures to be taken to avoid damage to the system; A sequential installation procedure; Repair or repl
12、acement instructions in the event that a system possesses flaws that would inhibit proper functioning and a list of sources where replacement components can be obtained; A maintenance schedule for all components; April 2007 Copyright 2007 NSF International Page 6 of 11 A sequential method for isolat
13、ing specific component failure. 5 Methods 5.1 System set-up and operation The system shall be installed according to manufacturers instructions for the intended end use. 5.2 Airborne particle reduction under normal operating conditions Testing to determine the effectiveness of the filtration media a
14、nd seals shall be conducted at an aerosol introduction point specified by the manufacturer. 5.2.1 Test procedure The manufacturer shall determine the aerosol induction point that provides the most uniform distribution (reference IEST-RP-CC-O34). Turn on the aerosol photometer and adjust in accordanc
15、e with the photometer manufacturers instructions. Sample the aerosol concentration upstream of the HEPA filter and verify that the concentration gives a light scattering intensity at least equal to that produced by 10 g/L of DOP. For linear readout photometers (graduated 0 100), adjust the instrumen
16、t to read 100 on the 100% scale. For logarithmic readout photometers, adjust the upstream concentration to 1 x 104above the concentration needed to produce one scale division (use the instrument calibration curve). With the nozzle of the probe held not more than 1.0 in (2.5 cm) from the area being t
17、ested, scan the entire downstream side of the HEPA filters, the air discharge point(s), and the seals between the HEPA filter and the hand dryer, by passing the photometer probe in slightly overlapping strokes at a traverse rate of not more than 2 in/sec (5 cm/sec). Record the results. 5.3 Ability t
18、o dry hands within a specified drying time The unit shall be allowed to run for a period of either one operating cycle or 15 seconds, whichever is shorter. This cycle time will be verified to a tolerance of 1 second. A panel of three adult men and three adult women will be randomly selected. The dim
19、ensions of the panel members hands shall be within the dimensions presented by AdultData The Handbook of Adult Anthropometric and Strength Measurements Data for Design Safety. Mean maximum hand spread: measured from the other border of the tip of the little finger to the outer tip of the thumb: Male
20、 212.9 mm 5%; Female 200.2 mm 5%. April 2007 Copyright 2007 NSF International Page 7 of 11 Mean middle finger height: measured from the tip of the middle finger to a line through the wrist crease: Male 193.3 mm 5%, Female 174.9 mm 5%. The test is to be carried out under standard room temperature (23
21、 5C, 73.4 9F) and humidity (55 5%) conditions with climatically conditioned equipment that had been stored in standard room conditions for a minimum of 24 hours. 5.3.1 Test Procedure The user shall remove jewelry (rings, bracelets, watches, etc.) and thoroughly wash their hands using a readily-avail
22、able hand soap and warm water prior to the start of the test. Weigh folded paper towel (Scott Multi-Fold Towels, Product Code 01804, size 23.88 cm x 23.62 cm or equivalent) on a digital scale and record weight. Place hands in bucket containing water (at a temperature of 37C, 98.6F) up to the hand-wr
23、ist crease level for a minimum duration of five seconds, rubbing hands in water to remove air traps and bubbles. Remove hands from bucket and let water drip from hands for five seconds (do not shake) while moving to position under machine. Use the hand dryer as instructed by the manufacturer. If the
24、 manufacturers instructions include rubbing hands together, the user shall rub hands together at the rate of two times per five seconds. When the dryer shuts off, dry excess water from hands (including between fingers and wrist) with the weighed paper towel until hands feel dry. Roll the used paper
25、towel into a ball and place back on the digital scale within five seconds. Reweigh the water-absorbed towel and record weight. The difference in weight between the water-absorbed towel and the dry towel is the residual moisture. 5.4 Plenum seals test This test shall be conducted when the interstitia
26、l space between the HEPA filter and pump operates in a pressure condition where an unacceptable flow of unfiltered air could enter into the plenums and be discharged at the effluent point. 5.4.1 Test Procedure Remove exterior panels and other access obstructions, where necessary, to expose plenums t
27、o be tested. Attach a manometer, pressure gauge, or pressure transducer system with a minimum accuracy of 0.08 in w.g. (20 Pa) to a point of maximum vacuum for the seal (typically close to the motor inlet). In case of doubt, use a series of pressure taps following the air path to determine the maxim
28、um vacuum point. April 2007 Copyright 2007 NSF International Page 8 of 11 Attach sealed ducting either to the inlet or to the effluent point with an in-line flow meter of minimum 2% of reading accuracy. The ducting and measurement system must offer minimal restriction to the airflow; otherwise measu
29、rements should be compensated for the flow loss caused. Run the hand dryers motor at the rated voltage and measure the interior pressure (vacuum) during normal operation. Remove the ducting and seal off any parts subject to positive pressure. Remove the HEPA filter and seal the hand dryers air intak
30、e. Attach a vacuum source with in-line flow meter of minimum 0.1 L/min accuracy to the sealed area away from the pressure tapping. De-pressurize the sealed area to match the normal operation interior pressure (vacuum) and measure the leakage flow rate through the vacuum source. 5.5 Disinfection of h
31、andwash effluent (if applicable) If the hygienic commercial hand dryer is equipped with a reservoir to collect and disinfect the handwash effluent, this test procedure shall be used to evaluate the bacterial and fungal disinfection capabilities of the unit. 5.5.1 Test Procedure Fungal Disinfectant E
32、fficacy o The procedure described in ASTM E2315-03Standard Guide for Assessment of Antimicrobial Activity Using a Time-Kill Procedure shall be followed. o Trichophyton mentagrophytes (ATCC 9533) shall be utilized as the challenge organism. o 10 carriers shall be evaluated. o The following amendments
33、 to the test conditions shall be utilized: 500 ppm hard water (calculated as CaCO3); 5% blood serum addition to test water. Bacterial Disinfectant Efficacy o The procedures described in ASTM E2315-03Standard Guide for Assessment of Antimicrobial Activity Using a Time-Kill Procedure shall be followed
34、. o Pseudomonas aeruginosa (ATCC 15442), Staphylococcus aureus (ATCC 6538) and Salmonella choleraesuis (ATCC 10708) shall be utilized as the challenge organisms. o 10 carriers shall be evaluated. o The following amendments to the test conditions shall be utilized: 500 ppm hard water (calculated as C
35、aCO3); 5% blood serum addition to test water. The vendor shall specify the disinfection chemical and the minimum anticipated concentration of the chemical in the handwash effluent and the minimum contact time period of the disinfection chemical with the handwash effluent. This concentration and Apri
36、l 2007 Copyright 2007 NSF International Page 9 of 11 contact time shall be used in the test. If no contact time is specified, 5 minutes shall be utilized as the exposure time. 5.6 Burn resistance test The burn resistance test shall be conducted on each surface or sample of each surface (including al
37、l treatment and storage containers) that can hold a lighted cigarette. All test surfaces shall not ignite, progressively glow, smolder, or show evidence of being functionally impaired during or after testing in accordance with the following method. 5.6.1 Test Procedure For each test surface, select
38、3 cigarettes from a freshly opened package of cigarettes. Light all 3 cigarettes and place them on the test surface. If possible, place them 25 mm (1 in.) from the edge and 50 mm (2 in.) from each other. Allow the cigarettes to burn for 2 minutes 2 seconds. Remove the cigarettes and allow the surfac
39、e to cool for 1 minute. 5.7 Test observations The following items shall be monitored during testing: liquid containment; ability to dry hands; odors; and noise. 6 Acceptance Criteria 6.1 Noise Any continuous noise, measured at a distance of one meter directly in front of the system, shall not exceed
40、 90 dBA. Any periodic noise associated with unit operations shall not exceed 100 dBA. 6.2 Airborne particle reduction under normal operating conditions When the hand dryer is challenged with an upstream concentration with an aerosol of 10 g/L of DOP particles, or an equivalent fluid, at a flow rate
41、equivalent to the rated flow of the hand dryer, and the emitted air is analyzed with an aerosol photometer, the sustained aerosol penetration shall not exceed 0.03% of the upstream concentration at any point. 6.3 Ability to dry hands within a specified drying time The unit shall be 95% effective at
42、achieving a residual hand moisture content of 0.1 g or lower within one operating cycle or 15 seconds, whichever is shorter, when the test is replicated a minimum of 20 times. April 2007 Copyright 2007 NSF International Page 10 of 11 6.4 Plenum seals The operational intent of a hygienic commercial h
43、and dryer is to prevent the hand dryer from using air contaminated with microbes to dry a users hands. No scientifically peer-reviewed research or regulations identifying typical or acceptable levels of microbes in indoor air are readily available. However, studies available on the U.S. EPA website1
44、indicate that an upper threshold of 500 CFU/m3of culturable bacteria may be found in indoor office environments. This threshold value can be restated so that 1 CFU/min would be present in a 2 L/min flow of air. We can incorporate the operational intent of a hygienic hand dryer and the hand dryers op
45、erating cycle to express an acceptance criterion that states the allowable leak rate shall be less than the 0.5 CFU/min threshold divided by the operating cycle established in Section 6.3. For example, at an operating cycle time of 15 sec (0.25 min), plenum seal leak rate of 2 / 0.25 or 8 L/min woul
46、d result in 1 airborne culturable bacteria being emitted per operating cycle, so the acceptance criteria would be less than 8 L/min. 6.5 Disinfection of handwash effluent (if applicable) Fungal Disinfectant Efficacy: For Trichophyton mentagrophytes, a 4-log reduction in concentration shall be achiev
47、ed within 5 minutes or a vendor-specified time period less than 5 minutes. Bacterial Disinfectant Efficacy: For Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella choleraesuis, a 6-log reduction in concentration shall be achieved within 5 minutes or a vendor-specified time period less tha
48、n 5 minutes. 6.6 Burn resistance test All test surfaces shall not ignite, progressively glow, smolder, or show evidence of being functionally impaired during or after testing. 1Tsai, FC; Macher, JM; Hung, Y-Y. Concentrations of Airborne Bacteria in 100 U.S. Office Buildings. Proceedings: Indoor Air
49、2002. Downloaded 9 April 2007 from U.S. EPA website: www.epa.gov. April 2007 Copyright 2007 NSF International Page 11 of 11 Annex A Program Specific Policies for Hygienic Commercial Hand Dryers A.1 Marking the product In addition to that required in the NSF Certification Policies for NSF Protocols and Non-NSF Standards, certified individual products or packaging materials should bear the following information: A.2
