Cal. Code Regs. tit. 3, § 6454 – Chloropicrin and Methyl Bromide--Structural Fumigation.

(a) When fumigating a structure, the fumigator shall ensure that the distance between the fumigated structure and its property line shall meet the following criteria and that no person, other than the fumigation crew, enters the area prescribed in either (1), (2), or (3) below during the treatment period:
1. (1) For fumigations utilizing 50 pounds of methyl bromide or less, a distance of at least five (5) feet must exist; or
2. (2) For fumigations utilizing more than 50 pounds, but less than 80 pounds, a distance in feet calculated using the following formula must exist:
  5 times the total poundage of methyl bromide minus 240 feet; or
3. (3) For fumigations utilizing 80 pounds or more, a distance in feet equal to two (2) times the total poundage of methyl bromide applied must exist.
(b) Structures shall be covered with the required tarpaulins or sealed prior to fumigation. The “acceptable” tarpaulin used in fumigations shall be vinyl coated with a minimum weight of seven (7) ounces per square yard (or having a fumigant retention capability equal to or greater than that provided by the seven-ounce weight tarpaulin). The vinyl coating shall not be worn, cracked, abraded, or similarly damaged to the extent that any of the underlying fabric shows through the vinyl coating.
(c) All cuts, tears, holes, or similar damage to tarpaulins shall be repaired prior to introduction of the fumigant. Temporary repairs to damaged tarpaulins shall be made with vinyl coated self-adhesive tape, or the damaged area of the tarpaulin may be rolled and clipped so the tarpaulin's fumigant gas retention capability is maintained.
(d) Fumigators shall use the fumigant retention method specified in the table below for the application rate and poundage combinations utilized in the fumigation:
Methyl Bromide Application Rate Per 1,000 Cubic Feet of Structure
Total Pounds of M ethyl Bromide Applied in a 24-hour Period
Fumigant Retention Method
Up to 0.5 pounds
Not more than 20 pounds
“acceptable” tarpaulin
More than 20 pounds, but less than 1,000 pounds
“acceptable” tarpaulin, or if the structure is a concrete tilt-up, seal with vinyl coated self-adhesive tape
More than 0.5 pounds Up to 1.5 pounds
Not more than 50 pounds
“acceptable” tarpaulin and a side drape of either: (1) an “acceptable” tarpaulin or (2) an unused 4-mil disposable polyethylene sheet
More than 50 pounds, but less than 1,000 pounds
“acceptable” tarpaulin, or if the structure is a concrete tilt-up, seal with vinyl coated self-adhesive tape
More than 1.5 pounds Up to 3.0 pounds
Not more than 50 pounds
“acceptable” tarpaulin and a side drape of one unused 4-mil disposable polyethylene sheet
More than 50 pounds, but less than 1,000 pounds
“acceptable” tarpaulin, or if the structure is a concrete tilt-up, seal with vinyl coated self-adhesive tape
(e) When tarpaulins are used, all sides of the structure shall be draped to the ground. Sand snakes, water snakes, or similar weights shall be used to seal the base of the tarpaulins to the ground. Prior to the placement of these snakes or weights, the soil adjacent to the structure foundation shall be thoroughly watered.
(f) Chloropicrin shall be used as a warning agent when fumigating a structure unless specifically prohibited by regulations or product labeling.
(g) A fan shall be used to disperse chloropicrin and methyl bromide within the structure. Chloropicrin shall be released into the airstream of the fan when it is introduced (either by itself or in combination with methyl bromide).
(h) Aeration of the fumigated structure shall not begin earlier than one hour after sunrise or later than one hour before sunset. The sunrise and sunset times published in the local newspaper shall be used to establish aeration timing.
(i) Following treatment, the fumigated structure shall be aerated through convection tubing or ducting. Except as provided in subsection (j), the convection tubing or ducting outlet shall be located above the highest point of the roof as follows:
1. (1) Six (6) feet for fumigations utilizing 50 pounds of methyl bromide or less; or
2. (2) Ten (10) feet for fumigations utilizing more than 50 pounds of methyl bromide.
(j) If any nearby structure is taller than the fumigated structure and the distance between the structures is equal to or less than the distance indicated in the following table, the convection tubing or ducting outlet shall be located as high as the top of the roof of the tallest structure.
Total Pounds of Methyl Bromide Applied
Convective Tubing or Ducting Outlet Must Be As High As the Tallest Structure Within:
1-14
50 ft.
15-24
75 ft.
25-32
100 ft.
33-40
125 ft.
41-50
150 ft.
51-60
175 ft.
61-99
200 ft.
100-1,000
A distance in footage equal to 2 times the pounds of methyl bromide used
(k) When aerating a fumigated structure, a licensed Branch 1 operator or field representative shall ensure, from the initiation of the aeration procedure to completion of the steps described in (n) of this section, that persons not involved in the aeration process do not come within:
1. (1) Ten (10) feet of the fumigated structure, for fumigations utilizing 50 pounds of methyl bromide or less; or
2. (2) For fumigations utilizing more than 50 pounds but less than 80 pounds, a distance in feet calculated using the following formula must exist:
  5 times the total poundage of methyl bromide minus 240 feet; or
3. (3) The number of feet equaling two (2) times the pounds of methyl bromide used for fumigations utilizing more than 80 pounds.
(l) Exhaust fans and convection tubing or ducting may be installed prior to aeration or when covering the structure with tarpaulins in preparation for fumigation. The exhaust fans, convection tubing, and installation of the fans and tubing shall meet the following requirements:
1. (1) Each exhaust fan shall have a capacity of at least 5,000 cubic feet per minute (cfm).
2. (2) Convection tubing or ducting shall be large enough to fit over the exhaust fan housing and shall be securely attached to the housing prior to aeration.
3. (3) Exhaust fans and convection tubing shall be installed in a manner which does not present a hazard to workers and the public.
(m) If exhaust fans and convection tubing or ducting are installed after the fumigation has begun, the installer shall wear self-contained breathing apparatus (SCBA) respiratory protection.
(n) The methyl bromide concentration shall be measured at the approximate center of the structure with a Fumiscope®, or similar instrument, that shall be located outside of the fumigated structure. (An instrument similar to a Fumiscope® may be used provided it can measure methyl bromide concentrations at the one ounce per 1,000 cubic feet [250 ppm] level.) Without entering the structure, the fumigator shall collect the methyl bromide sample for measurement through the use of tubing or ducting placed inside the structure and connected to the analytical instrument prior to the initiation of fumigation. The structure shall be aerated until the methyl bromide concentration has been reduced to 250 ppm or less (250 ppm is about one ounce per thousand cubic feet) while following the requirements listed below:
1. (1) If the fumigated structure's windows were left open during the fumigation, the structure shall be aerated through convection tubing or ducting until the methyl bromide concentration is 250 ppm or less with the tarpaulins left in place; or
2. (2) If the fumigated structure's windows were closed during the fumigation:
  1. (A) The space between the fumigated structure and the tarpaulin shall be aerated prior to tarpaulin removal through convection tubing or ducting.
  2. (B) After the tarpaulins are removed, the fumigated structure shall be aerated through convection tubing or ducting until the methyl bromide concentration is 250 ppm or less.

This section supplements the methyl bromide fumigation requirements found in the Business and Professions Code and Title 16 of the California Code of Regulations, as well as directions for use given on methyl bromide product labeling.

Note: Authority cited: Sections 11456, 12976, 12981, 14005 and 14102, Food and Agricultural Code. Reference: Sections 11501, 12981, 14006 and 14102, Food and Agricultural Code.

History

1. Editorial renumbering of former section 2453(d) to section 6454 filed 8-13-85 (Register 85, No. 33).

2. Amendment of section heading and Note and new subsections (c)-(f) filed 4-14-92 as an emergency; operative 4-14-92 (Register 92, No. 18). A Certificate of Compliance must be transmitted to OAL 8-12-92 or emergency language will be repealed by operation of law on the following day.

3. Amendment of section heading and Note and new subsections (c)-(f) refiled 8-14-92 as an emergency; operative 8-14-92 (Register 92, No. 33). A Certificate of Compliance must be transmitted to OAL 12-12-92 or emergency language will be repealed by operation of law on the following day.

4. Amendment of section heading and Note and new subsections (c)-(f) refiled 12-18-92 as an emergency; operative 12-18-92 (Register 92, No. 51). A Certificate of Compliance must be transmitted to OAL 4-17-93 or emergency language will be repealed by operation of law on the following day.

5 Amendment of section heading and Note and new subsections (c)-(f) refiled 3-29-93 as an emergency; operative 3-29-93 (Register 93, No. 14). A Certificate of Compliance must be transmitted to OAL 7-27-93 or emergency language will be repealed by operation of law on the following day.

6. Repealer of subsections (c)-(f) and reinstatement of section heading and Note as they existed prior to emergency amendments filed 12-1-93, effective 7-28-93 by operation of Government Code section 11346.1(f) (Register 93, No. 49).

7. Editorial correction of History 3, 4, 5, and 6 (Register 94, No. 30).

8. Repealer and new section and amendment of Note filed 8-15-2000; operative 9-14-2000 (Register 2000, No. 33).