Page 418 - Industrial Ventilation Design Guidebook

6.3 TARGET VALUES FOR THERMAL FACTORS: AN OVERVIEW OF INTERNATIONAL STANDARDS 373

identified to allow elimination of the hazardous agents through process de-
sign, engineering control, or other administrative practices to keep exposures
within acceptable limits. A new assessment should be made to check the new
situation, and periodic measurements should be done to check that control
measures remain effective.
In any case, the risk assessment must be documented in a suitable report,
including the existing working conditions and the reasons for the chosen pro
cedures. It should contain, at least, the following data:
* The names of the chemical agents considered
• The description of the workplace factors
» The description of the working conditions during the measurements
* The measuring procedure
» The time schedule
* The results of occupational exposure concentrations
• All events or factors liable to influence the results
• Results of the comparison with the OEL

Retention of this data is essential for future work in order to compare and an-
alyze successive sets of assessment exposures.

Bibliography
American Conference of Governmental Industrial Hygienists. Threshold limit values for chemical
substances and physical agents and biological exposure indices. ACGIH, Cincinnati, OH,
1999.
The Council of the European Union. Council Directive 98/24/EC of 7, April 1998 on the protec-
tion of the health and safety of workers from the risks related to chemical agents at it'ork. Offi-
cial Journal No. LI31, May 1998.
European Committee for Standardization. EN 689:1. Workplace atmospheres: Outdance for the
assessment of exposure to chemical agents for comparison with limit values and measurement
strategy, \ 995.

6.3 TARGET VALUES FOR THERMAL FACTORS: AN OVERVIEW OF INTERNATIONAL
STANDARDS

6.3.1 Introduction
The main purpose for the heating and air conditioning of work spaces is to
provide an environment that is acceptable and does not impair the health and
performance of the occupants. During production processes and in the exter-
nal environment it may be necessary to work in unacceptable conditions for a
limited time period. However, it must be ensured that these conditions do not
impair the health of the employees. Light, noise, air quality, and the thermal
environment are all factors that influence the acceptability of conditions for
and performance of the occupants. This section will only deal with the ther-
mal environment. Several standards dealing with methods for the evaluation
of the thermal environment have been published by international standard or-
ganizations such as ISO and CEN.