1. Quality Assurance of Reagents, Supplies, And Laboratory Water

2. In order to produce high quality work, a laboratory requires a constant supply of good quality reagents, supplies and water
A deficiency of any of these can cause the most efficient laboratory either to come to a standstill or to provide substandard service

3. Choice and Evaluation of Reagents and Supplies
A selection of a brand of reagent for instrument system or laboratory tests is made after searching and gathering information concerning the reagent sensitivity, preparation, storage, and cost
Next, an evaluation of the selected material is performed in the laboratory, comparing the new reagent to the old
If the comparison is favorable, the new reagent is purchased

4. Choice and Evaluation of Reagents and Supplies
Before committing to purchase insists on performing a field trial of the reagent
Factors that should be considered in selecting and evaluating a new reagent or material supplies are:
Sensitivity
Stability and storage conditions
Vendor reputation
Delivery time
Cost

5. Laboratory Inventory Management
Effective inventory control involves setting up a system that has the following goals:
Simplify and reduce paperwork
Improve communication between the laboratory and the other hospital departments involved in purchasing, stocking, and paying for supplies
Manage inventory so that Shortages and overstocking should be avoided
Teaching laboratory employees better budgeting and materials management techniques

6. Inventory Control Program
Designing and implementing an inventory control program involves :
The identification of the needed supplies
Their rate of use
Periodic review and evaluation of the inventory and ordering process

7. Inventory Control Program
Conduct a survey to list all of supplies that the laboratory uses, the list should include:
The name of the item
A brief description
Approximate usage per month
Current vendor
Order unit amount
Current unit packing, that is per box, carton, or bag
Order or catalogue number
Priority of need
Assigning an item its relative importance
High priority: if needed constantly or cannot be done without
Medium priority: if needed occasionally
Low priority: if needed rarely

8. Inventory Control Program
The next step is to determine the order point, order quantity and lead time for the item
Order point: the sum of the minimum inventory plus the emergency supply
The level of inventory at which an order is generated
Lead Time: is the length of time between initiating an order and receiving it in the laboratory

9. Inventory Control Program
Controlling inventory involves the counting, storage and movement of supplies within the laboratory
A written record system of inventory levels and checks should be devised
Three types of record systems are suggested:
The periodic count
Strict inventory control is not required
Count of materials weekly or every two weeks, when count reaches the order point, an order is generated
Good for small to midsize Lab.

10. Inventory Control Program
The perpetual inventory record
Strict inventory control is required
Inventory is closed to lab. Personnel, one or two persons manage it
Good for larger lab.
The specialized inventory record
Used for slow-moving, infrequently ordered parts such as instrument spare parts
Parts are not ordered until inventory is used
Once the inventory system has been set up, it should be reviewed annually for updating

11. Reagents Prepared in the Lab.
Reagents, standards and controls prepared in the laboratory from stock chemicals should be:
Prepared using class A volumetric glassware and properly calibrated balances
To eliminate variation (batch to batch), preparation should be limited to one or two persons
Label each reagent, standard, and control with the following:
The name of the material
The procedure for which the material is to be used
Date of preparation
Date of expiration
Initials of the person who prepared it

13. Laboratory Water
Reagent - grade water must be properly purified and periodically inspected for:
Electrical resistivity
Resistivity (R) of water is the measurement of electrical resistance and is the inverse of electrical conductivity (C)
R and C are directly related to the number of inorganic ions and conduction particles in the water
The greater the ionic concentration, the greater the electrical conductivity and the less the electrical resistance
Measurements are made using a resistivity or conductivity meter
Soluble silica concentration
measured by a chemical reaction between silicate and molybdate ions to form a blue complex

14. Laboratory Water
Desired pH
The pH is measured with pH meter
Bacterial contamination
The microbiological content of the water is defined as the number of colony - forming units per milliliter of water
Three recommended methods:
Pour plate (1 ml of water)
membrane filtration
or calibrated loop for sampling (0.01 ml)
If organic free water is desired , soluble organic materials can be removed using charcoal filter

15. Laboratory Water
Purification of water can be achieved through 3 methods:
Distillation
Deionization
Reverse osmosis
Additional purity is obtained with charcoal filtration.
Membrane capacitive deionization
Membrane capacitive deionization (MCDI) is a water desalination technology based on applying a cell voltage between two oppositely placed porous electrodes sandwiching a spacer channel that transports the water to be desalinated

16. Water Grades According to Purity
Type I water:
The highest level of purity,
used for:
tissue and cell culture methods
special and critical analytical chemical analysis
and in preparation of standard solutions
Type II water:
Used for most routine quantitative clinical laboratory methods
It should be stored for short periods of time before use, to prevent change in resistivity and bacterial growth

17. Water Grades According to Purity
Type III water:
The least pure
Suitable for most qualitative procedures including:
Urine analysis
parsitology
and histology
Suitable for glassware washing
Stored in containers that protect it form contamination

18. Three of Clinical Laboratory Water