BS 692:1990

Foreword
Committees responsible
Specification
1 Scope
2 Types
3 Temperature scale
4 Stem
5 Bulb
6 Annealing
7 Stabilization
8 Immersion
9 Scale lines
10 Figuring
11 Construction
12 Sheath
13 Top finish
14 Expansion chamber
15 Spirit filling
16 Maximum and minimum thermometers: special provisions
17 Inscriptions
Appendices
A Thermometric glasses approved by the National
    Physical Laboratory
B Testing of meteorological thermometers
C Method of test for the absence of amines in spirit
    filling
D Meteorological thermometers with a Fahrenheit scale
Tables
1 Dimensions for meteorological thermometers
2 Ranges and tolerances for meteorological
    thermometers (Celsius scale)
3 Identification stripe(s) or approved abbreviations
    and normal maximum working temperature of all
    glasses that have been approved for the manufacture
    of thermometer bulbs
4 Ranges and tolerances for meteorological
    thermometers (Fahrenheit scale)
Figures
1 Suitable support for thermometers in a louvred
    screen
2 Typical graduation and figuring for British
    Standard Celsius meteorological thermometers
3 Details of button at top of ordinary thermometer
4 Details of clips on thermometer support

Maximum, minimum and ordinary (i.e. wet and dry bulb) glass-sheathed thermometers suitable for mounting in a louvred screen. Comply with MOD and Meteorological Office requirements (Celsius scale) for worldwide use. Essential dimensions, maximum errors, specification for ethanol in spirit-filled thermometers. Requirements for Fahrenheit scale given in appendix.

This British Standard range of meteorological thermometers comprises the following types. thermometers protected by glass sheaths and suitable for mounting in a louvred screen (see Figure 1).

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.