To facilitate instruction, include shared teacher observation, preparation and storage rooms between each pair of wet chemistry and physical science laboratories.

These storage/prep rooms house additional science equipment storage cabinets with counters and separate lockable steel cabinets for safe and secure storage of chemicals and valuable equipment.

The storage and prep feature large demonstration windows into each adjacent laboratory, which make it possible for teachers to demonstrate an experiment behind glass, or to supervise students while they are preparing a lesson.

Storage and Preservation of Materials

Types of Stores

In most secondary schools, there are found two types of stores namely the main stores and the dispensing stores. For the science section, there is a main science store and the materials housed are applicable to the science teaching in the school. Petty issues to individuals are not allowed from the main store. The main science store only issues out complete containers and case to individual dispensing stores such as the Biology, Chemistry, and Physics stores. The dispensing stores, located at each laboratory, are set up mainly for the purpose of issuing out equipment and apparatus to students at that particular laboratory.

Characteristics of Stores

Ideally the main science store should be located at the rear of the building and at the ground floor convenience of delivery of goods. The store must be large enough to accommodate all the necessary stock and yet leave ample room for trolleys to move about.

Good lighting is essential in the store. The fittings must be placed high enough above the stacks to give good distribution of light in the day and should wherever possible be spaced between stacks so as to give illumination to the gangway.

All necessary safety precautions must be adopted in the stores.

2.5.1 System of Location of Items

In the laboratories, storerooms, preparation rooms and workshops, there are always found storage spaces such as cabinets, cupboards, shelve s, racks, side bench drawers and many others. The types of facilities vary according to different schools. Nevertheless, all the storage spaces must be clearly labeled to indicate the types of materials being stored. Besides clear labeling, the storage spaces must be suitably coded. By this it means every storage space is given a code and this is a means of locating the item in the process of stock-checking. For example, there may be five cabinets in Physics laboratory number one and five more in Physics laboratory number two. No doubt, all the items contained in the cabinets are clearly indicated on the outside of the individual cabinets; but in the process of stock-checking, it is often more convenient to check every item in accordance with the stock-cards which are usually arranged in alphabetical order and also contain information on location of every item in a coded form. For example, 10 ohm resistors may be located at PIC3. This code means the resistors are kept in Physics laboratory number 1 and cabinet number 3. Hence any person doing stock-checking cans easily pin-point the location of any item. The types of codes used may be different but they must be simple and do not cause confusion.

Coding of storage spaces not only helps in stock-checking but also helps solve some teething problems. Too often it is found that only the laboratory attendant in a particular laboratory knows where items are kept. A science teacher who needs any set of items is too used to inform the laboratory attendant and get them from him. Troubles usually arise when this laboratory attendant is on leave or being transferred. No one seems to know where a certain piece of item is kept and the poor science teacher has to hunt every storage space to locate for this item. Sometimes a certain experiment has to be abandoned because a particular item cannot be found. Such a thing would occur if the storage space is properly coded. The science teacher has only to check the stock card for location of any item.

But one implementation rule that must be strictly adhered to is that every item that has been issued must be returned to its original position after use. If such a rule is not observed, items may be then misplaced and it is extremely difficult to locate them again especially for small items like capacitors, resistors and others.

2.5.2 Important Documents in Stores

Important documents in the stores must be properly filed and kept in locked cabinets. Except for the laboratory staff, no other persons should be allowed to have access to these documents unless with prior permission from the senior science teacher. References to these documents should only be carried out in the laboratories and loaning them out of the laboratories should be discouraged unless it is absolutely necessary.

The following are some of the important documents usually kept in the stores:

1. Quotations
2. Orders
3. Acknowledgement letters
4. Delivery notes
5. Invoices
6. Instructional manuals
7. Catalogues
8. Pamphlets
9. Stock-cards
10. Others

Except for stock-cards, all the documents above are common documents and needed no further description. Stock-cards are the most important documents in the stores as they contain relevant information to every single item kept in the store. An involved system of recording is unnecessary as paper work must be kept to a minimum. Nevertheless they should contain enough relevant information to all the items kept in the laboratory.

Stock-cards are usually arranged in alphabetical order and it is useful to separate chemicals from the other apparatus, that is, there are two types of stock-cards, one for chemicals and one for apparatus and equipment.

2.5.3 Chemicals

It is necessary that chemicals should be segregated from other equipment and apparatus. When it comes to the matter of storage, this is necessary because of the unique nature of the chemicals such as hydroscopic, poisonous, deliquescent and others generally chemicals may be grouped under two main categories: Inorganic and organic.

Because chemicals tend to deteriorate with age, a constant check at regular intervals on their condition of stock is, therefore, necessary. The old stock should be used up before the new and in this respect the easiest way is to stamp (or write) the date on each bottle as it is received and to place the new stock at the back of the shelves.

For dangerous chemicals, it is important that they should be clearly labeled and stored under lock and key in special cupboards. Periodic checks on these bottles for dropping or fading of labels are required and replacement made if necessary. Chemicals are stored in alphabetical order.

a)      Inorganic Chemicals

         These should be arranged under the name of the metal. The shelves should be labeled accordingly. Double compounds such as ammonium nickel sulphate or ferrous ammonium sulphate or ferrous ammonium sulphate tend to create some confusion but this can be overcome if the normal method of labeling, as adopted by the suppliers of chemicals are placed in the shelves accordingly, in any case such as matters are put right by the adoption of a procedure suitable to the store and by cross reference and location marks on the stock cards.

The prefixes to the names of chemicals, such as di, tri, ortho, and meta are ignored for storage purposes and such chemicals are stored in the normal way under the name of the metal.

For example, triammonium orthophosphate would be stored with the ammonium compounds. Ferric and ferrous are stored under the metal iron.

b)      Organic Chemicals 

Organic chemicals present much more difficulty storage of these chemicals in classes such as alcohol, ether and acid may be convenient for the selection of substances or certain class exercises, but the system is not convenient for storage purposes, organic chemicals should be kept in alphabetical order in employing this system the prefixes such as o, m and p are ignored. Other prefixes, however such as di, and tri, should be taken into account for purposes of alphabetical location. This is generally done m suppliers catalogues so that if the normal system of the chemical supplier is adopted it simplifies the store arrangement.

c)      Glassware

The size of the items of glass apparatus stored should be standardized as for as possible. They should not be placed too high and mixed with heavy apparatus or metal articles. Tall glass apparatus should be stored at the back of shelves and smaller pieces in front. Special pieces of glassware, for example, Kipp’s apparatus, are stored as far as possible in their original packing and paper containers. Make sure the packages are labeled.

Glassware is stored according 10 its type and size. All flasks, for instance, should be stored in neighboring bins but separated according to size. Flat bottom vessels may stand upright but round bottom vessels should be stored in a bin with high front small glassware, such as clock glasses, specimen tubes, Petri dishes and microscopic slides, are best kept in shelf trays. Burettes require a long padded drawer or a stand. All expensive glassware should be separately packed in soft wadding. Thermometer should be kept in their cardboard-cases and stored according to type and range.

d)      Glass Tubing and Rods

Horizontal storage for glass tubing or glass rod is undoubtedly the best. The tubing must be well supported along its length to prevent sagging which is often noticeable in glass tubing which has been stored vertically large-diameter tubing’s must be plugged at the ends to keep out dust Soda glass and hard glass should be kept as far apart as possible.

Glass tubing should be stored by weight (i.e. light, medium and heavy wall) and each weight of tubing is stored according to STS outer diameter. It is convenient if a table of sizes, including wall thickness and allowed tolerances is hung close to the glass tubing storage racks. The tubing is normally delivered in 1.5m lengths and keeps much cleaner if stored in its original packing.

e)      Plastics

Plastics apparatus should be stored away from heart sources if it is brittle, it should not be stored with heavy apparatus.

f)       Metal wares

Metal wares such as clamps, boss heads, tripod stands, Bunsen burners should be stored together and they need periodic maintenance.

g)      Apparatus

The numerous small items found in the laboratory are usually kept in drawers or trays. Optical items such as lenses, mirrors and prisms are kept in drawers with packets of silica gel to maintain dryness.

Bigger apparatus are always arranged in shelves. Those heavy ones are placed below and the lighter ones a top of the shelves.

h)      Electrical Parts

Electrical equipment and components should be stored in a group, away from fumes and chemicals. Valves transistors and other delicate items should be wrapped in cotton wool and placed in individual casings.