(4w) The outside end of the ducts shall be equipped with a suitable weatherproof fitting or vent-head designed to prevent foreign matter from entering or obstructing the duct. The effective area of the openings in such fittings or vent-heads shall be at least equal to the cross-sectional area of a 4-inch duct. The horizontal section of the ducts shall be as short as practical and shall be pitched to prevent the accumulation of liquids in the line. The number of bends and offsets shall be reduced to a minimum and provisions shall be incorporated to facilitate the periodic cleaning of the ducts.
PSC 135.187 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99.
PSC 135.189PSC 135.189Vaults: drainage and waterproofing additions [49 CFR 192.189].
PSC 135.189(1)(1)After 49 CFR 192.189(a), insert:
(aw) Nevertheless, vault equipment shall always be designed to operate safely, if submerged.
PSC 135.189(2)(2)After 49 CFR 192.189(c), insert:
(cw) Electrical equipment in vaults shall conform to the applicable requirements of the state electrical code, chs. SPS 316 and PSC 114.
PSC 135.189 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; correction in (2) made under s. 13.92 (4) (b) 7., Stats., Register December 2012 No. 684.
PSC 135.195PSC 135.195Protection against accidental overpressuring additions [49 CFR 192.195]. After 49 CFR 192.195(b)(2), insert:
(3w) Suitable types of protective devices to prevent overpressuring of high-pressure distribution systems include:
(i) Spring-loaded relief valves of types meeting the provisions of the ASME Unfired Pressure Vessel Code.
(ii) Pilot-loaded back-pressure regulators used as relief valves, so designed that failure of the pilot system or control lines will cause the regulator to open.
(iii) Spring loaded diaphragm-type relief valves.
(iv) A monitoring regulator installed in series with the primary pressure regulator.
(v) A series regulator installed upstream from the primary regulator, and set to continuously limit the pressure on the inlet of the primary regulator in accordance with the provisions of 49 CFR 192.201.
(vi) An automatic shut-off device installed in series with the primary pressure regulator, and set to shut off in accordance with the provisions of 49 CFR 192.201. This device shall remain closed until manually reset. It may not be used where it might cause an interruption in service to a large number of customers.
(4w) Suitable types of protective devices to prevent overpressuring of low-pressure distribution systems include:
(i) A liquid seal relief device that can be set to open accurately and consistently at the desired pressure.
(ii) A series regulator, as described in s. PSC 135.195 (3w) (v).
(iii) An automatic shut-off device, as described in s. PSC 135.195 (3w) (vi).
(iv) A pilot loaded back-pressure regulator, as described in s. PSC 135.195 (3w) (ii).
(v) A monitoring regulator, as described in s. PSC 135.195 (3w) (iv).
(cw) Suitable types of protective devices to prevent overpressuring of gas pressure holders, pipelines and other facilities that might at times be bottle tight include:
(1) Spring-loaded relief valves of types meeting the provisions of the ASME Unfired Pressure Vessel Code.
(2) Pilot-loaded back-pressure regulators used as relief valves, so designed that failure of the pilot system or control lines will cause the regulator to open.
PSC 135.195 HistoryHistory: Cr. Register, October, 1999, No. 526, eff. 11-1-99; corrections made under s. 13.93 (2m) (b) 7., Stats., Register February 2004, No. 578; correction made under s. 13.92 (4) (b) 7., Stats., Register February 2011 No. 662.
PSC 135.197PSC 135.197Control of the pressure of gas delivered from high-pressure distribution systems additions [49 CFR 192.197]. After 49 CFR 192.197(c), insert:
(dw) The service regulator shall be of a type that is capable under normal operating conditions of regulating the downstream pressure within the limits of s. PSC 134.23 and of limiting the build-up of pressure under no-flow conditions to 50% or less of the discharge pressure maintained under flow conditions.
(ew) In addition to the provisions of 49 CFR 192.197(a) and (b), if the maximum actual operating pressure of the distribution system is greater than low pressure and is equal to or less than 60 p.s.i.g., a suitable protective device shall be installed to prevent unsafe overpressuring of the customer’s appliances should the service regulator fail. These devices may be installed as an integral part of the service regulator or as a separate unit. Some of the suitable types of protective devices to prevent overpressuring of customers’ appliances are: