N.H. Admin. Code § Env-A 1221.03

Current through Register No. 50, December 12, 2024

Section Env-A 1221.03 - Compliance Standards for Open Top Vapor Degreasers

Open top vapor degreasers shall be controlled using the control equipment, techniques, and operating requirements described below:

(a) Control equipment shall consist of the following:

(1) A cover, located below the lip exhaust, if any, that can be opened and closed easily without disturbing the vapor zone;

(2) Safety switches, as follows:

a. Equipment preventing heat input to the sump when the condenser coolant is not circulating or when the liquid solvent level drops down to the height of the sump heater coils;

b. Equipment preventing spraying outside the vapor level; and

c. Equipment that shuts off the sump heat if the upper vapor level rises above the height of the primary condenser;

(b) Control techniques shall consist of the following:

(1) For degreasers with an open area equal to or greater than one m², equivalent to 10.8 ft², at least one of the following techniques or combination of techniques:

a. The combination of:

1. A freeboard ratio greater than or equal to 0.75; and

2. A powered cover;

b. An enclosed design, such as a cover or door which opens only when the dry part is actually entering or exiting the degreaser;

c. A refrigerated chiller that is capable of maintaining the chilled air blanket temperature, measured at the centroid of the degreaser at the coldest point, at no more than 30% of the solvent's boiling point (F); or

d. A carbon adsorption system meeting the requirements of (c), below; and

(2) For degreasers with an open area less than one m², equivalent to 10.8 ft², at least one of the following techniques:

a. A freeboard ratio greater than or equal to 0.75; or

b. An enclosed design, such as a cover or door which opens only when the dry part is actually entering or exiting the degreaser;

(c) A carbon adsorption system installed pursuant to (b)(1)d., above, shall comply with the following operational requirements:

(1) Ventilation greater than or equal to 15 m³/min per m², equivalent to 50 cfm/ft² of air/vapor area when cover is open; and

(2) Exhausting less than 25 ppm solvent averaged over one complete adsorption cycle or 24 hours, whichever is less; and

(d) Operating requirements shall be as follows:

(1) The cover shall be kept closed at all times except when processing work loads through the degreaser;

(2) Solvent carry-out shall be minimized by using the following measures:

a. Racking parts to allow full drainage;

b. Moving parts in and out of the degreaser at less than 3.3 m/min, equivalent to 11 ft/min;

c. Degreasing the work load in the vapor zone at least 30 seconds or until condensation ceases, whichever is longer;

d. Tipping out any pools of solvent on the cleaned parts before removal; and

e. Allowing parts to dry within the freeboard zone of the degreaser for at least 15 seconds or until visually dry, whichever is longer;

(3) The unit shall not be used to degrease porous or absorbent materials, such as cloths, leather, wood, or rope;

(4) Work loads shall not occupy more than half of the degreaser's open top area;

(5) The degreaser shall not be loaded to the point where the vapor level would drop more than 10 centimeters, equivalent to 4 inches, when the workload is removed from the vapor zone;

(6) No spraying shall occur above the vapor level;

(7) Solvent leaks shall be repaired immediately, or the degreaser shut down;

(8) The evaporation of waste solvent into the ambient air shall not exceed 20% of the weight of the waste during the process of:

a. Disposing of the waste solvent; or

b. Transferring the waste solvent to another person;

(9) Waste solvent shall be stored only in closed containers;

(10) Exhaust ventilation shall not exceed 20 m³/min per m², equivalent to 65 cfm per ft², of degreaser open area, unless necessary to meet OSHA requirements;

(11) Drafts shall be minimized across the top of each degreasing unit such that whenever the cover is open, the unit is not exposed to drafts greater than 40 meters, equivalent to 131 feet, per minute, as measured between 1 and 2 meters, equivalent to 3.3 and 6.6 feet, upwind and at the same elevation as the tank lip;

(12) Water shall not be visually detectable in solvent exiting the water separator; and

(13) A permanent, legible, and conspicuous label, summarizing the operating requirements listed above, shall be affixed to each solvent container or other location where it can be easily seen by the operator.

N.H. Admin. Code § Env-A 1221.03

(See Revision Note at chapter heading for Env-A 1200) #9933, eff 6-1-11

Amended by Volume XXXIX Number 46, Filed November 14, 2019, Proposed by #12899, Effective 10/17/2019, Expires 10/17/2029