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Swimming bath waters and drinking waters at residential schools were examined.
Pending the authorisation by the appropriate Ministry of the expenditure for installing
automatic treatment plants at these baths, they continued to be treated by an
improvised chlorination system.
Instructional visits of school parties to both the County Hall and the Northern
Outfall Works laboratories should be mentioned.
Supplies
The materials examined for this service covered a very wide field and many of
them are dealt with in other paragraphs concerning the services which use them;
for example, paints and building materials for housing. Many foodstuffs of all types
were examined, the main purposes being (a) to allocate contracts to the tenderers of
the cheapest satisfactory material, (b) to check the quality of deliveries, (c) to
investigate complaints and (d) to assess whether new preparations could be of potential
use in the service. Generally, a high standard of quality was maintained for the
foodstuffs in use and there were only a very few justifiable complaints. A careful
watch was kept on the quality of the liquid milk supplied and condensed and dried
milks were examined as required. Other materials which might be mentioned
included chemicals, drugs and medical supplies, lubricating and other oils, floor and
other polishes, soaps, etc.
Careful attention was given to the use of synthetic detergents and an alteration
was made in the formulation of the Council's specification for washing-up powder
which increased its efficiency and decreased the cost.
Fire Brigade
Much of the work in this field was of a consultative and advisory nature, including
the discussions of the British Standards Institution's Technical Committees on
Inflammability of Films and Definitions of Fire Resistance and Incombustibility.
Investigations and laboratory tests were undertaken in a number of cases including:—
(a) the cause of a fire attributed to smouldering in the groove of a board
after the use of a blow lamp: (b) in another case the theory of spontaneous
combustion could not be supported; (c) rubber fire hose, foam producing
compounds, fire resisting paints and protective coatings were examined.
Steamraising,
heating, etc.,
plants
Much consultative and advisory work was done for both the Chief Engineer's
and Architect's departments involving examinations in situ and subsequent analysis
of samples in the laboratory regarding scale formation, scale removal and corrosion
problems. The use of sodium hexametaphosphate for scale prevention and of soda
ash and quebracho or full phosphate conditioning for boiler water was extended;
the dosages were controlled by periodical analysis of the water concerned.
Examples of special cases dealt with were:—
(a) Corrosion of some elements of a gas fired heating boiler was ascribed to
the action of steam on red hot iron and faulty circulation of the water in the
boiler; (b) 85 per cent. magnesia plastic and hard setting compounds were
examined as to compliance with the Council's specification. Other suggested
materials for heat insulation purposes containing slag wool and diatomaceous
earth were also tested for comparison.
Miscellaneous
Many other matters were dealt with of which a few examples can be given:—
(a) plastic materials for use in lampshades, etc., were examined as to the
temperature at which deformation occurred under varying degrees of stress,
and the discoloration produced by light; (b) comparison of different types of
tracing paper used for plans as to dimensional changes occurring with varying
temperature and humidity; (c) a number of inleakages of water into basements
were examined as to the source from which the water was derived (e.g., mains,
sewer, or ground); (d) electric cable sheathing was examined for rubber content,
etc., and also for traces of metals which accelerate deterioration of the rubber;
(e) a commercial "drain tester" was examined and considered to have an element
of danger associated with its use; (f) air conditions in show cases at an exhibition
were examined to prevent deterioration of valuable documents.