[Code of Federal Regulations]
[Title 40, Volume 11]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR63.1294]

[Page 211-212]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 63--NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES--Table of Contents
 
 Subpart III--National Emission Standards for Hazardous Air Pollutants 
                for Flexible Polyurethane Foam Production
 
Sec. 63.1294  Standards for slabstock flexible polyurethane foam production--diisocyanate emissions.

    Each new and existing slabstock affected source shall comply with 
the provisions of this section.
    (a) Diisocyanate storage vessels. Diisocyanate storage vessels shall 
be equipped with either a system meeting the requirements in paragraph 
(a)(1) of this section, or a carbon adsorption system meeting the 
requirements of paragraph (a)(2) of this section.
    (1) The storage vessel shall be equipped with a vapor return line 
from the storage vessel to the tank truck or rail car that is connected 
during unloading.
    (i) During each unloading event, the vapor return line shall be 
inspected for leaks by visual, audible, or any other detection method.
    (ii) When a leak is detected, it shall be repaired as soon as 
practicable, but

[[Page 212]]

not later than the subsequent unloading event.
    (2) The storage vessel shall be equipped with a carbon adsorption 
system, meeting the monitoring requirements of Sec. 63.1303(a), that routes 
displaced vapors through activated carbon before being discharged to the 
atmosphere. The owner or operator shall replace the existing carbon with 
fresh carbon upon indication of breakthrough before the next unloading 
event.
    (b) Transfer pumps in diisocyanate service. Each transfer pump in 
diisocyanate service shall meet the requirements of paragraph (b)(1) or 
(b)(2) of this section.
    (1) The pump shall be a sealless pump; or
    (2) The pump shall be a submerged pump system meeting the 
requirements in paragraphs (b)(2)(i) through (iii) of this section.
    (i) The pump shall be completely immersed in bis(2-
ethylhexyl)phthalate (DEHP, CAS #118-81-7), 2(methyloctyl)phthalate 
(DINP, CAS #68515-48-0), or another neutral oil.
    (ii) The pump shall be visually monitored weekly to detect leaks,
    (iii) When a leak is detected, it shall be repaired in accordance 
with the procedures in paragraphs (b)(2)(iii)(A) and (B) of this 
section, except as provided in paragraph (d) of this section.
    (A) The leak shall be repaired as soon as practicable, but not later 
than 15 calendar days after it is detected.
    (B) A first attempt at repair shall be made no later than 5 calendar 
days after the leak is detected. First attempts at repair include, but 
are not limited to, the following practices where practicable:
    (1) Tightening of packing gland nuts.
    (2) Ensuring that the seal flush is operating at design pressure and 
temperature.
    (c) Other components in diisocyanate service. If evidence of a leak 
is found by visual, audible, or any other detection method, it shall be 
repaired as soon as practicable, but not later than 15 calendar days 
after it is detected, except as provided in paragraph (d) of this 
section. The first attempt at repair shall be made no later than 5 
calendar days after each leak is detected.
    (d) Delay of repair. (1) Delay of repair of equipment for which 
leaks have been detected is allowed for equipment that is isolated from 
the process and that does not remain in diisocyanate service.
    (2) Delay of repair for valves and connectors is also allowed if:
    (i) The owner or operator determines that diisocyanate emissions of 
purged material resulting from immediate repair are greater than the 
fugitive emissions likely to result from delay of repair, and
    (ii) The purged material is collected and destroyed or recovered in 
a control device when repair procedures are effected.
    (3) Delay of repair for pumps is also allowed if repair requires 
replacing the existing seal design with a sealless pump, and repair is 
completed as soon as practicable, but not later than 6 months after the 
leak was detected.