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CURRENT ISSUE
NOISE
Advances in Understanding Noise Exposures
The new NIOSH agenda for hearing loss prevention research contains significant new insights from the latest science concerning hearing loss, which impacts communication in the workplace. The document also presents critical new information regarding age correction and vulnerable populations.
PERSONAL PROTECTIVE EQUIPMENT
Respirator Use at High Altitudes
Does an SCBA (self-contained breathing apparatus) respirator protect wearers from oxygen-deficient atmospheres due to increasing altitude? The answer may surprise you.
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The Importance of NORA
As a practitioner, you have knowledge that's critical to developing research agendas to help improve workers' well-being. It's important that your voice is heard and that your needs are represented in your country's research agenda.
PROFESSIONAL DEVELOPMENT
INDOOR ENVIRONMENTAL QUALITY
After the Fire
From the August 2016 issue: The potential human health effects of wildfire smoke and residues often remain unanswered. How do we evaluate the potential health hazard posed by wildfire residue?
PRESIDENT'S MESSAGE
Progress in International Collaboration
AIHA's president provides an update on progress toward the organization's goals for international engagement: developing professionals, fostering community, and increasing awareness of occupational health and safety.
BY THE NUMBERS
Driver Fatigue
A new page on the NIOSH website focuses on how to prevent driver fatigue on the job. Driver fatigue can be caused by being awake for many consecutive hours, not getting enough sleep over multiple days, and monotonous tasks or long periods of inactivity.
SPONSORS
ERGONOMICS
Exercising Judgment with Office Furniture
While the health benefits of "active" workstations may appear obvious, occupational health and safety professionals need to consider their potential impacts on workplace safety and productivity.
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ETHICS
Updates to the Code of Ethics
The American Board of Industrial Hygiene recently created a new, high-level umbrella organization to more accurately reflect its enhanced credential offerings. A key part of establishing this new structure is to unify the existing codes of ethics for the individual credentials.
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FROM THE ARCHIVES
SAMPLING AND ANALYSIS
The ABCs of Wildfire Residue Contamination Testing
From the November 2017 issue: Testing can be an essential component in addressing "invisible" contamination concerns during postfire assessments or determining if any residual contamination is above the "normal" or "typical background" levels. But what to test for and how to use the results are big questions without clear resolutions.
CHEMICAL AND MATERIAL HAZARDS
Electronic Cigarettes and the IH
From the May 2019 issue: AIHA’s white paper on e-cigarettes was recently updated to discuss the latest research on e-cigarette hazards. How should industrial hygienists and safety and health professionals address the occupational and public health concerns associated with e-cigarettes?
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The official publication of the American Industrial Hygiene Association
Although the print version of The Synergist indicated The IAQ Investigator's Guide, 3rd edition, was already published, it isn't quite ready yet. We will be sure to let readers know when the Guide is available for purchase in the AIHA Marketplace.
 
My apologies for the error.
 
- Ed Rutkowski, Synergist editor
Disadvantages of being unacclimatized:
  • Readily show signs of heat stress when exposed to hot environments.
  • Difficulty replacing all of the water lost in sweat.
  • Failure to replace the water lost will slow or prevent acclimatization.
Benefits of acclimatization:
  • Increased sweating efficiency (earlier onset of sweating, greater sweat production, and reduced electrolyte loss in sweat).
  • Stabilization of the circulation.
  • Work is performed with lower core temperature and heart rate.
  • Increased skin blood flow at a given core temperature.
Acclimatization plan:
  • Gradually increase exposure time in hot environmental conditions over a period of 7 to 14 days.
  • For new workers, the schedule should be no more than 20% of the usual duration of work in the hot environment on day 1 and a no more than 20% increase on each additional day.
  • For workers who have had previous experience with the job, the acclimatization regimen should be no more than 50% of the usual duration of work in the hot environment on day 1, 60% on day 2, 80% on day 3, and 100% on day 4.
  • The time required for non–physically fit individuals to develop acclimatization is about 50% greater than for the physically fit.
Level of acclimatization:
  • Relative to the initial level of physical fitness and the total heat stress experienced by the individual.
Maintaining acclimatization:
  • Can be maintained for a few days of non-heat exposure.
  • Absence from work in the heat for a week or more results in a significant loss in the beneficial adaptations leading to an increase likelihood of acute dehydration, illness, or fatigue.
  • Can be regained in 2 to 3 days upon return to a hot job.
  • Appears to be better maintained by those who are physically fit.
  • Seasonal shifts in temperatures may result in difficulties.
  • Working in hot, humid environments provides adaptive benefits that also apply in hot, desert environments, and vice versa.
  • Air conditioning will not affect acclimatization.
Acclimatization in Workers