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Room 156: Aquatic Toxicology Research Room

This unique aquatic research room is set up inside an environmental chamber. The room itself is a stainless steel-lined Constant Temperature environmental chamber with air temperature control ranging between 5°C-30°C. This air temperature can be alarmed to ±1°C.

Animal Holding Room

Room: This room is a 40 m² environmental chamber. The walls, ceiling and fan units are stainless steel. The floor is a special hardened concrete to prevent water penetration. There is a grate covered trench located along the center of the room. The drain line for the tanks is located within this trench, as is a drain to the sanitary sewer.

The door for animal holding room and the anteroom has a covered window built into it to allow inspection of the room without entry. The door covering the window should remain closed at all times while not in use. There are no handles located in the anteroom.

To exit the animal holding room push on the left side of the door until it opens.

There are no catches to hold the door closed, only a mechanical door closure. There is provision to lock the door. If the door were to be locked while someone was still in the room, a release mechanism is located on the wall inside the room beside the door. Spin the knob until it comes completely off and push on the left side of the door until it opens.

Temperature control: Air temperature in the animal holding portion of the room ranges from 5°C - 25°C and is controlled by the Argus™ system. Temperatures are fully programable, the air temperature could follow a diurnal pattern, rising and dropping with the photoperiod. Temperature is monitored by a thermistor located within the room. The Air Temperature Deviation Alarm can be set to activate with as little as ± 1°C change.

Tanks:

Biofiltration: The biofiltration for this room is accomplished in the gravel bed located in the anteroom. New biofilters need time to grow bacterial cultures. Nitrosomonas sp. grows first, converting ammonia to nitrite. There is a lag time before Nitrobacter sp. starts to grow. It is during the time that Nitrobacter sp. is becoming established that elevated levels of nitrite could become dangerous to fish. Nitrobacter sp. converts nitrite to nitrate a much less toxic form of organic nitrogen.

Aeration: Low pressure air for tank aeration is supplied through black ABS pipe that circles the room. Air is supplied from three 1 hp Gast regenerative air blowers located in room 174.

Power: This room has five 115 V and two 250 V electrical circuits. There are two duplex receptacles per 115 V circuit. These are located around the perimeter of the room. Each circuit has a duplex ground fault receptacle. If power is lost to a receptacle, check the buttons located in the middle of the ground fault receptacles. If one is sticking out, press it back in to reset the power. If power is lost again, report it to Aqualab personnel. A circuit breaker panel is located on the wall in the anteroom. Please do not open this panel without proper authorization.

Lights: This room has a combination of fluorescent and incandescent lights in weatherproof fixtures. The room has a fully programmable photoperiod (i.e., the photoperiod can be programmed to emulate that found at any latitude in the world or any artificial photoperiod that the researcher requires). At “dawn” the incandescent bulbs slowly ramp up to full intensity, then the fluorescent lights turn on sequentially in three steps. At “dusk” the process reverses with the incandescent bulbs slowly ramping off at “sunset” Photoperiod is monitored by a light sensor located in each room. The Photoperiod Alarm is set to activate if the lights do not turn on or off as the program requires. The lights can be turned on manually from the Argus™ panel located in the hall outside Room 181. An alarm situation will occur if the lights are left on too long.

Alarms: There are a number of parameters within the room that can be alarmed. As previously mentioned, there is an alarm for photoperiod and air temperature deviation. There is also a Control Override for the chamber itself. If the air temperature rises above 28°C or drops below 15°C, the control system will cut all power to the chamber. Immediately the system will go into the highest alarm state and activate the Control Override Alarm, an audible alarm and the auto dialer will be activated to notify personnel of the problem. Power will be restored when air temperature returns to normal or by the Facility Manager. Operating in conjunction with the control override are manual temperature controllers. These manual controllers also act to cut power to the chamber during times of temperature extreme. These manual controls need to be reset after environmental conditions are changed usually at the beginning of new experiments. There is also a Low Air Pressure Alarm on the regenerative air system.

Anteroom:

Room: The water treatment system is located in the anteroom and consists of a 2m x 2m x 1.5 m deep sump, two pumps, a screen filter, a one bulb UV sterilizer and three plate heat exchangers. The effluent sump pit is also located here.

The anteroom is also supplied with a sink with hot and cold domestic water, and cupboards above and below the sink for limited storage of chemicals and equipment. A fire extinguisher is located beside the door. Windows in the doors provide visual access to both rooms.

To exit the anteroom push on the left side of the door until it opens.
There are no catches to hold the door closed, only a mechanical door closure. There is provision to lock the door. If the door were to be locked while someone was still in the room, a release mechanism is located on the wall inside the room beside the door. Spin the knob until it comes completely off and push on the left side of the door until it opens.

Water Temperature Control: Water temperature is controlled and monitored by the Argus™ system and consists of two plate heat exchangers supplied with both hot and cold glycol. Water temperature is monitored going in and out of the exchanger by thermistors located in the pipes. These thermistors are set to activate an alarm (Water Temperature Deviation Alarm) if the water temperature deviates from the target temperature by a preset margin.

The computer control system regulates the position of two two-position three-way actuated valves to provide either hot or cold glycol. An actuated modulating valve regulates the amount of glycol supplied to the heat exchanger to maintain the target water temperature. The range of water temperatures in this room is approximately 3°C - 25°C. There is a small amount of flexibility in the system, which is governed by the flow rate of water through the exchanger and the surface area of the plates found in the exchanger itself.

Water Replacement: Water is added to the room’s recirculation system on a regular basis. The volume added is controlled by the Argus™ system which in turn controls the make-up water solenoid valve. The make-up water system is composed of a paddlewheel flow sensor and a solenoid valve on a 1" PVC supply line . Water is fed directly from Aqualab’s pre-filtration system into the room’s sump pit.

Water Recirculation: Water is recirculated around the room from the sump pit to the tanks and back again. Two pumps, located beside the sump pit, draw water through the gravel bed filter located in the sump pit and pump it through the UV sterilizer, and the plate heat exchangers. After the water is filtered and the temperature is modified, it travels to the tanks in the animal holding room. Water overflows stand pipes located within each tank and returns via drain lines to the sump pit. Water is filtered through a rotating screen filter before it passes through the gravel bed filter. The drain lines are found in the trench. Each set of tanks has a set of blade valves to direct flow either into the trench (for cleaning and disinfection) or back to the sump (for recirculation).

Recirculation water flow is monitored by paddlewheel flow sensors which are set to activate an alarm when flow drops below a preset level (Low Flow Alarm). The preset level is dependent upon the minimum required water flow. A No Flow Alarm situation occurs when the pumps shut down.

System Water Volume: The water level in the sump pit is monitored by an ultrasonic level sensor. When the water level drops below a preset point the make-up water solenoid valve opens. Water is added until the sump is once again full. If the water level drops below a preset level (setpoint 1) an alarm is activated (Low Water Level Alarm) and the make-up water solenoid opens. If the water level continues to drop past another prest level (setpoint2), the pumps will be turned off by the control system, to protect them from overheating and draining the sump pit. This will activate another alarm (No Flow Alarm). When the water level rises above the preset point (setpoint 2) the control system will reactivate the pumps, thereby restoring flow. With the resumption of flow the No Flow Alarm will be deactivated. When the water level rises above first preset point (setpoint 1) the Low Water Level Alarm will be deactivated.