Figure 7-1。  Floor sweep

7-4。4 Ductwork。  See paragraph 2-4。1 for general ductwork design。  See NFPA 664 for specific requirements on wood shop ductwork construction。  Size the ductwork to maintain a minimum transport velocity as specified in the ACGIH IV Manual, Chapter 10, Woodworking。 Use only metal ductwork and conductive flexible hose。 Bond and ground all ductwork in accordance with NFPA 664。 The ductwork must be designed on the basis that all hoods and other openings connected to the system are open。

7-4。5 Blast Gates。  Provide blast gates only for the specific purpose of balancing the airflow。 Do not use blast gates to isolate equipment from the exhaust system with the intent to reduce the overall airflow requirement。 When possible, install blast gates on horizontal runs and orient the gate so the blade is on the top half of the duct and opens by pulling the blade towards the ceiling。 When possible, blast gates

must be installed at a location not easily accessible to shop personnel。 After final balancing and acceptance, secure the blade and mark its position so that it can be returned to the balanced position if inadvertently moved。 When the blast gate cannot be placed out of the reach of shop personnel, then lock the blade in position。 For example, drill a hole through the body and blade of the gate and then insert a bolt and tack weld  it。

7-4。6。 Duct Support。  If sprinkler protection is provided in the duct, horizontal ductwork must be capable of supporting the weight of the system, plus the weight of the duct half-filled with water or material being conveyed, whichever has the higher density。

7-4。7 Clean Out Panels。  See paragraph 2-4。1。 7-4。8 Exhaust Fans。  See paragraph 2-4。2。

7-4。9 Weather Stack Design and Location。  See paragraph 2-4。3。

7-4。10 Air Cleaning Devices。  See paragraph 2-4。4。  Locate the air-cleaning device outside the building。

7-4。11 Heating and Air Conditioning。  Provide heating and cooling according to MIL-HDBK-1003/3。

7-5 SAFETY AND HEALTH CONSIDERATIONS。 See paragraph 2-7 and the following items。

a。 Refer to section 7。2。2 of ANSI O1。1, Woodworking Machinery, Safety Requirements for personal protective equipment。

b。 Provide a means for separately collecting and disposing of any metal scrap such as nails, band iron, or any wood containing metal。 Do not use the woodshop ventilation system to pick up these materials。

c。 Avoid the use of wood painted with paints containing lead, hexavalent chromium, cadmium, or coated with wood preservatives。 Otherwise, consult an industrial hygienist to determine the exposure level and the level of respiratory protection needed。

d。 Use sharp and clean blades at the correct feed rate to generate less heat。 The generated heat can raise the wood or wood-containing product to ignition temperature that could start a fire。

CHAPTER 8

BATTERY MAINTENANCE FACILITIES

8-1 FUNCTION。 Battery maintenance facilities contain space and equipment for receiving, cleaning, testing, charging, and issuing batteries。 Sizes range from a small booth to a room with storage area。 In these facilities, batteries are not in operation while being charged。 Two types of electrochemical battery in general use are lead-acid and nickel-cadmium (NICAD)。 This chapter does not address battery-post repair operation。 Design of facilities for installation of battery banks, such as UPS, will be covered in a different UFC。