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Occupational Heat Stress and Heat Strain
The following materials are intended
to support the ACGIH® TLV® for heat stress and strain, but
I have taken some liberties. The materials are copyrighted.
It would be nice to hear from you by email if you download anything
from this site.
This site is undergoing a number of
revisions to reflect new research and guidance. Some downloads have
been removed and others are not yet updated. The following is a
copy of a final report to NIOSH that examines the role of clothing
in heat stress evaluation.
The TLV® for heat stress and strain
was described in a webinar offered by the ACGIH® in April of
2006. The worksheets used are provided below. Please see the ACGIH®
website for information on obtaining a copy of the webinar.
Basic Tools (top
of page) |
| Psychrometric
Relationships
Can be used to determine other psychrometric properties from
any two and can be used to estimate natural wet bulb temperature. |

Analysis Package
v 1.0 (1/22/05) |
Qualitative
Tools (top
of page) |
Qualitative Exposure Assessment
Two methods are provided. One has been
published and the other reflects some of my thoughts (unpublished). |

Qual Exp Ass't
v 1.0 (8/19/01) |
Semi-Quantitative (top
of page) |
| WBGT
Screening for Heat Stress |

Manual Screen
v 2.2 (4/14/06) |
Recovery Allowances
Charts that specify the percent of a cycle
to allow for recovery. |
|
Quantitative (top
of page) |
| WBGT
The basic time-weighted average method for exposure assessment.
Analysis Package has routines to estimate WBGT.
|

Analysis Package
v 4.0 (4/1/06) 
Manual Method
v 3.2 (4/14/06) |
| Rational
Heat Stress Analysis Package
Underdevelopment
|
|
Short-Term Exposure Limit
An empirical relationship to recommend
time limits for high heat stress exposures based on WBGT and
allowing for metabolic rate and clothing.
Beta Version: The relationship is not
published or peer-reviewed, and it may evolve. Version 0.2
corrects a problem with the °F curve.
This is currently unpublished. Comments
are welcome. |

Analysis Package v 0.2 (1/16/08) |
Estimation of Exposure
Time with Ice Cooling Personal Protection
An estimate of the amount of time a person
can stay in a hot environment while wearing a personal cooling
system with an ice heat sink.
|

Manual Method
v 1.0 (2/5/07) |
| Estimation of
Metabolic Rate
Methods include ISO and Qualitative Descriptors plus equations
for selected activities.
The newest versions (v3 for Analysis Package and v2 for Manual
Method) have an expanded set of equations including an adaptation
of Garg's equations to estimate metabolic rate. |

Analysis Package
v 3.1 (7/28/05) 
Manual Method
v 2.0 (8/6/06) |
|