BS 2486:1997

This standard BS 2486:1997 Recommendations for treatment of water for steam boilers and water heaters is classified in these ICS categories:

• 91.140.65 Water heating equipment
• 27.060.30 Boilers and heat exchangers
• 13.060.01 Water quality in general

This British Standard gives recommendations for the control of water-side conditions of steam boilers and water heaters and also for the preparation of feed water for such plant. The following categories of water heating or steam-raising plant are covered:

1. hot water systems as defined in 1.4;

2. electrode boilers;

3. shell (fire-tube) boilers operating at pressures up to 30 bar;²⁾

4. water-tube boilers operating up to critical pressure;

5. once-through boilers, including ‘coil’ and ‘hairpin’ types, operating up to, or above, the critical pressure.

NOTE 1. Regulation 11 of the Pressure Systems and Transportable Gas Containers Regulations, 1989 [2] came into effect on 1 July 1994 and requires boiler users to provide operators with adequate and suitable instructions for the safe operation of the boiler, and to ensure that the boiler is not operated, except in accordance with these instructions. Guidance given in the Health and Safety Executive᾽s Approved Code of Practice Safety of Pressure Systems [3] requires that instructions should cover, if appropriate, the feed water treatment.

NOTE 2. The Control of Substances Hazardous to Health (COSHH) Regulations 1994 [1] require an assessment of the risk of exposure to substances hazardous to health and implication of the control measures needed to prevent, or if that is not reasonably practicable, adequately control such exposure. All sources of exposure in the workplace are covered including releases resulting from explosion or venting. For further information users are advised to consult the Approved Codes of Practice covering the control of substances hazardous to health and control of carcinogenic substances [4].

The recommendations are not applicable to:

1. the treatment of water for most domestic heaters, which is covered by BS 7593 Code of practice for treatment of water in domestic hot water central heating systems;

2. the treatment of water for marine boilers, which is covered by BS 1170 Recommendations for treatment of water for marine boilers;

3. the treatment of water for nuclear-powered steam-generation plant.

The use of electronic, electrostatic or magnetic products is outside the scope of this standard. The preparation of a future British Standard covering such physical treatments of water for steam boilers and water heaters is being considered.

Methods for the analysis of water are not described in this standard.

Additional information on water and water treament is given in annexes A to D.