As summer heat intensifies, OSHA’s focus on preventing heat related illness intensifies. With this intensity, many employers are going hi-tech to collect “heat exposure data” to establish work practices based on exposures. I have seen a recent increase in advertising for devices that can measure wet-bulb temperatures in workplaces and they are tying these reading back to complying with OSHA’s Heat Illness Prevention efforts. Portable heat stress meters or monitors are used to measure heat conditions. These instruments can calculate both the indoor and outdoor WBGT index according to established ACGIH Threshold Limit Value equations. With this information and information on the type of work being performed, heat stress meters can determine how long a person can safely work or remain in a particular hot environment. Officially OSHA’s program is targeted toward “outdoor workers”, but factory workers can be at even greater risks due to poor working conditions such as non-existent ventilation and the need to wear semipermeable or impermeable protective clothing. I also need to point out that OSHA does NOT have any heat exposure limits, but they will enforce the ACGIH TLV’s. Here’s the thing… if you are using one of these Wet-Bulb measuring devices to measure employee’s working conditions related to heat and humidity, then these “samples” will in fact fall under 1910.1020(d)(1)(ii) and must be retained as “exposure records” for 30 years. Here is OSHA’s position…
Temperature and relative humidity measurements: These records may be employee exposure records under the standard. As stated in the Preamble (45 FR 35265), “…basic chemical manufacturing processes and abnormal exposures to heat, noise, and vibration are covered by the rule, but typical office working conditions are not.” Therefore, if the temperature and humidity measurements are abnormal, i.e., not typical office working conditions, they must be considered employee exposure records.
Source: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24255
Question 2:
“Does OSHA consider monitoring results for employees that show detectable levels below the applicable action levels and permissible exposure limits (‘PELs’) for an OSHA-regulated substance to be an ‘Employee exposure record’ as defined in 29 CFR 1910.1020(c)(5) that employers must preserve and maintain for 30 years pursuant to 1910.1020(d)(1)(ii)?”
Yes, employee exposure records that indicate an employee is exposed below the applicable action level or PEL are part of the employee exposure record as defined in 29 CFR 1910.1020(c)(5) that must be preserved and maintained in accordance with 1910.1020(d)(1)(ii). You are correct in your assertion that 1910.1020 does not intend to cover situations where the employer can demonstrate that the toxic substance or harmful physical agent is not used, handled, stored, generated, or present in the workplace in any manner different from typical non-occupational situations. The standard does, however, apply to occupational exposure below these levels. The preamble to the final rule clarifies:
For example, basic chemical manufacturing processes and abnormal exposures to heat, noise, and vibration are covered by the rule, but typical office working conditions are not. The applicability of the standard does not, however, depend on any showing that the level of actual exposure to a toxic substance or harmful physical agent is particularly excessive, but rather on the unique fact of occupational exposure. (45 FR 35265)
Source: https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=22719
OSHA’s Technical Manual; Section III, Chapter 4
Operations involving high air temperatures, radiant heat sources, high humidity, direct physical contact with hot objects, or strenuous physical activities have a high potential for inducing heat stress in employees engaged in such operations. Such places include: iron and steel foundries, nonferrous foundries, brick-firing and ceramic plants, glass products facilities, rubber products factories, electrical utilities (particularly boiler rooms), bakeries, confectioneries, commercial kitchens, laundries, food canneries, chemical plants, mining sites, smelters, and steam tunnels.
Outdoor operations conducted in hot weather, such as construction, refining, asbestos removal, and hazardous waste site activities, especially those that require workers to wear semipermeable or impermeable protective clothing, are also likely to cause heat stress among exposed workers.
Portable heat stress meters or monitors are used to measure heat conditions. These instruments can calculate both the indoor and outdoor WBGT index according to established ACGIH Threshold Limit Value equations. With this information and information on the type of work being performed, heat stress meters can determine how long a person can safely work or remain in a particular hot environment. See Appendix III:4-2 for an alternate method of calculation.