There are several types of PPE that can be used to protect workers from harmful hydrogen sulfide (H2S) exposure. Exactly what kind is necessary will depend on the conditions of each work site, including how much H2S gas is present and at what levels. The first line of defense should involve a qualified professional conducting a thorough assessment with testing monitors to determine how much of the H2S can be eliminated at the source. Following that, occupational health and safety best practices suggest that the employer implement and maintain control exposures with personal protective equipment (PPE) and safe work practices to reduce exposures (learn more about using the right equipment in Avoiding Injury: Reasons for Using the Correct Safety Equipment).
OSHA mandates what PPE is required when workers are either directly exposed to H2S or working near a site where the gas is present. Whenever respirators are used, the employer must have a respiratory protection program that meets the requirements of OSHA's Respiratory Protection standard (29 CFR 1910.134). This program must include proper respirator selection, fit testing, medical evaluations, and training (select the right device with 6 Factors to Consider When Choosing a Respiratory Protection Device). The exact respirator standards should be discussed with a qualified safety professional, but for the purpose of this Q&A, it should be noted t
hat the respirator must be a positive-pressure, self-contained breathing apparatus (SCBA
If you're using a full-face respirator, the eye protection is already part of the equipment. If the respirator you're using does not cover the eyes, additional eye protection will be needed, since prolonged exposure may cause nausea, tearing of the eyes, headaches or loss of sleep. For exposures at or above 100 ppm, there is a danger of "gas eye" and conjunctivitis with respiratory tract irritation. Exposures above 100 ppm are considered immediately dangerous to life and health, and employers will need to direct the use of a full face pressure demand self-contained breathing apparatus.
Fire Resistant Gloves and Clothing
Hydrogen sulfide is flammable, so protective gloves and clothing are needed in some cases. Again, the need for this extra layer of protection will depend on the work being done and the environment it is being done in. Weather conditions and temperatures can also have an impact and safety policy must include directives about this. H2S can corrode some materials, so the materials used in any PPE manufactured for the use of a worker exposed to H2S must meet industry standards and any compliance regulations. As always, when working in confined spaces, ventilation should operate continuously.
Proper PPE for use with H2S should be a part of the training and education for any workers and also any visitors who may become exposed to the gas on the work site. This training should include emergency plans, locations of safety equipment, rescue techniques and location of a safety line for rapid exit from a confined space or remote location (when needed), first-aid, and proper rescue procedures for first responders.