Asphalt fume inhalation
Recognition
Asphalt fumes are small particle clouds created through condensation after volatilization of asphalt. Asphalt fume inhalation is a cause of concern for over 300,000 workers employed in asphalt mixing facilities and paving sites. [1] The primary health effects of asphalt fume inhalation include irritation of the serous membrane of the eyelids and the mucus membrane of the nasal and oral tracts. Burning of the skin can occur with contact of hot fumes. In animal studies, it was found that localized tumours formed with asphalt left on skin. This finding has not been demonstrated in humans as of now. [2]
Evaluation
Occupational exposure to asphalt fumes has a recommended limit of 5 mg/m3 per 15-minute period by the Canadian Centre for Occupational Health and Safety. Although insufficient human studies and a limited number of experimental studies demonstrate genotoxicity and carcinogenicity associations to asphalt fumes, it is best to use the ALARA principle or keeping exposure As Low As Reasonably Achievable. [1]
Summary of Controls
Various control methods for asphalt fumes have been recommended by OSHA of the United States Department of Labour. [3]
Administrative Controls
In order to reduce exposure to asphalt fumes, one possible recommendation is that employers assign rotational duties to workers such that no one individual works with asphalt paving for a longer cumulative duration.
Education
Proper education and training in safety precautions against fume inhalation can help workers recognize and reduce toxic fume inhalation.
Substitution Controls
Low-fume emitting asphalt mixes can be substituted to reduce generation of asphalt fumes under high temperature conditions.
Engineering Controls
Heating systems that maintain a constant asphalt temperature and fume emission capture can be used. Furthermore, emission destruction devices consisting of a vent system that evacuates fumes from the headspace can be installed.
Personal Protective Equipment
The Centre for Disease Control and Prevention recommends specific personal protective equipment to reduce fume exposure. At concentrations above the recommended NIOSH exposure limit, a self-contained breathing pressurized apparatus,with a full facepiece is recommended. Respirators must be properly fitted by a professional. Additionally, gloves can be used to reduce skin contact with potentially dermal irritant fumes. [2]
References
- ↑ 1.0 1.1 Government of Canada, Canadian Centre for Occupational Health and Safety. (2017). CCOHS: Products & Services: NPG - Appendix C. Retrieved from <http://www.ccohs.ca/products/Supplements/NPG/appendixc.html>.
- ↑ 2.0 2.1 NIOSH. (2016). Asphalt fumes. Retrieved from <https://www.cdc.gov/niosh/npg/npgd0042.html>.
- ↑ OSHA. (n.d.). Asphalt Fumes. Retrieved from <https://www.osha.gov/SLTC/asphaltfumes/solutions.html>.