Relative Humidity Treatments of Pollen Environments
Department: Agronomy
Created by: Agustin Fonseca and Sebastian Schneider
Laboratory: Crop Production & Physiology
Supervisor: Mark Westgate
Lab Supervisor: Maria Hartt Eckerman
Date approved: 19 Feb 04
Procedure Overview: This procedure is used for the preparation of saturated solutions used to control environments at varying relative humidity.
Equipment and reagents necessary :
Distilled water (approximately 200 ml)
Glass beakers
Stirring hot plate/stir bar
Lithium chloride (15% Relative Humidity)
Calcium nitrate, tetrahydrate (50% Relative Humidity)
Sodium carbonate, anhydrous (85% Relative Humidity)
Procedure :
1. Place a heatproof glass beaker containing distilled water and stir bar on a stirring hotplate. Set heat to bring water to a temperature of ~ 60 ºC.
2. Add the desired reagent necessary to achieve proper relative humidity until saturation (reagent will start to precipitate).
3. Let the solution cool down; store at room temperature.
4. Clean the hotplate and all glassware used.
Personal Protective Equipment / Engineering Controls :
Protective gloves and clothing
Safety glasses
Adequate ventilation
Eyewash station
Safety shower
Hazard controls :
Calcium nitrate tetrahydrate: Do not get water inside containers or use combustible materials for spill cleanup.
Lithium chloride: Minimize dust generation & accumulation; do not get on skin or in eyes.
Sodium carbonate anhydrous: Minimize dust generation & accumulation
Waste Disposal & Decontamination Procedures :
Calcium nitrate tetrahydrate: Store with compatible solutes in tightly closed designated waste container in Hazardous Waste Satellite Accumulation Area.

Lithium chloride: Small amounts of liquid wastes can be safely flushed (using a plentiful amount of water) down a sanitary sewer that is connected to a sewage treatment plant. Solids should be placed in dumpster units.
Sodium carbonate anhydrous: Small amounts of liquid wastes can be safely flushed
(using a plentiful amount of water) down a sanitary sewer that is connected to a sewage treatment plant. Solids should be placed in dumpster units.
Health & Safety Info for Required Reagents :
Chemical name i n o g e
C a r c e v e n l l i v o s e r r
C o g e t o n r a
T e i x
T o c n t t a i r
I r
T l y o x g h i
H i c i z t i n s
S e e r
Target Organ i t u s l b
C o m b e s s r e e d
C o m p
G a s l b m a e l
F a m i v o s e l p
E x
P e n i c
O r g a i d e r o x s i z e r i d
O x o r p h r o
P y i c a b l e t s
U n a c r
R e t e
W a i t v e
Storage precautions and incompatibilities
Calcium nitrate tetrahydrate
Lithium chloride
X X Blood
X X X Central nervous system, cardiovascular
X X system
X X Incompatible with aluminum, ammonium nitrate
Bromine trifluoride, strongs acids
Sodium carbonate anhydrous
Silver nitrate, 2,4dinitrotoluene, 2,4,6trinitrotoluene, sulfuric acid, sodium sulfide + water, lithium, phosphorus pentoxide, fluorine, and hydrogen peroxide. Hot concentrated solutions of sodium carbonate are mildly corrosive to steel
.

The above summary consists of guidelines for proper handling & disposal of chemicals used in this procedure. You must read attached MSDSs for more specific information before using the procedure. a l
H e t h i l b i m a
F l a m t y i v i t a c
R e t y
2 0 1
2 0 0
3
1
0 0
2 03feb04 ss/af