New Jersey Administrative Code
Title 7 - ENVIRONMENTAL PROTECTION
Chapter 18 - REGULATIONS GOVERNING THE CERTIFICATION OF LABORATORIES AND ENVIRONMENTAL MEASUREMENTS
Subchapter 4 - MICROBIOLOGICAL TESTING
Section 7:18-4.2 - Requirements for environmental laboratory equipment, supplies and materials

i. Incubators and water baths shall be sized to accommodate periods of peak work load;

ii. Incubators and water baths must maintain internal temperatures as specified in the analytical method being performed;

iii. When aluminum block incubators are used, culture dishes and tubes shall fit snugly within the block;

iv. The water bath shall be equipped with a calibrated temperature monitoring device graduated in increments of at least 0.2 degrees Celsius; and

v. Whenever an air incubator is in use, a calibrated temperature monitoring device with its sensor or bulb immersed in liquid shall be placed on the topmost and bottommost shelf in use within the incubator. If only one shelf in the incubator is in use, the calibrated temperature monitoring device shall be placed on that shelf.

i. The autoclave shall be in good operating condition when observed during its operational cycle or when time temperature charts are read;

ii. The autoclave shall be equipped with an accurate temperature monitoring device and a working safety valve;

iii. The autoclave shall be equipped with an accurate pressure gauge, unless the laboratory has documentation from the manufacturer of the autoclave certifying that the equipment will operate safely without a pressure gauge;

iv. The autoclave shall reach the sterilization temperature of 121 degrees Celsius, maintain that temperature throughout the sterilization period, and complete the autoclave cycle in no more than 45 minutes when a 12 to 15 minute sterilization period is used for culture media; and

v. During depressurization, the autoclave shall not produce air bubbles in the fermentation media.

i. The hot air oven shall be able to maintain a stable sterilization temperature of 170 to l80 degrees Celsius for at least two hours;

ii. Hot air ovens shall be used for sterilization of glass pipets, bottles, flasks, culture dishes, and other laboratory glassware and utensils; and

iii. A calibrated temperature monitoring device in increments no larger than 10 degrees Celsius with its sensor or bulb placed in sand shall be placed on one of the shelves in use within the hot air oven.

i. At least one low-power magnification device with 10 to l5x magnification, for use in counting membrane filtration colonies;

ii. A fluorescent light source for use in counting total coliform MF colonies;

iii. A mechanical hand tally for use in counting bacteria colonies; and

iv. A colony counter, dark field model, to count Heterotrophic Plate Count colonies.

i. The diameter of inoculation loops shall be at least three millimeters and the loops shall be constructed of 24 to 26 gauge Nichrome, chrome, or platinum-iridium wire;

ii. Either single-service metal inoculation loops, pre-sterilized plastic inoculation loops, or reusable metal inoculation loops shall be used; and

iii. Disposable dry-heat-sterilized hardwood applicator sticks may be used.

i. Units used in MF procedures shall be made of stainless steel, glass, or autoclavable plastic;

ii. MF equipment shall not leak and shall not be corroded; and

iii. Field equipment may be used for coliform and all bacterial analysis using the membrane filter procedure; however, standard laboratory MF procedures must be followed when using field equipment.

i. Membrane filters shall be manufactured from cellulose ester materials, and shall be white, grid-marked, and have a 47 millimeter diameter and 0.45 micrometer ([mu] m) pore size; however, another pore size may be used when the performance data provided by the manufacturer show the performance of that pore size to be equal to or better than the performance of the 0.45[LESS THAN] micro m membrane filter; and

ii. Membrane filters and pads shall be either autoclavable or presterilized.

i. Sterile, glass or plastic pipets shall be used for measuring quantities of 10 milliliters or less; and shall be accurate within a 2.5 percent tolerance or less;

ii. Glass pipets shall be made of borosilicate glass; and

iii. Pipets shall not be excessively etched, mouthpiece or delivery tips shall not be chipped, and graduation marks shall be legible.

i. Open packs of disposable sterilized pipets shall be resealed after each use; and

ii. Pipet containers shall be made of aluminum or stainless steel or individual pipets shall be wrapped in char-resistant paper.

i. Sterile plastic culture dishes with tight or loose lids, or glass culture dishes with loose lids shall be used; and

ii. When culture dishes with loose lids are used, the relative humidity in the incubator shall not be less than 90 percent.

i. Culture dish containers shall be made of either aluminum or stainless steel, or the culture dishes shall be wrapped in heavy aluminum foil or char-resistant paper; and

ii. Open packs of disposable sterile culture dishes shall be resealed after each use.

i. Culture tubes shall be made of borosilicate glass or other corrosion resistant glass and shall be of a sufficient size to contain both the culture medium and the sample portions to be tested, without being more than three-quarters full; and

ii. Caps should be made of snug-fitting stainless steel or plastic; however, loose-fitting aluminum caps or screw caps with non-toxic liners are also acceptable.