EPA 608 Core Practice Questions with Explanations

Answer: A. CFCs are sufficiently stable to reach the stratosphere, where ultraviolet radiation releases chlorine that destroys ozone. They do not dissolve in rain as B suggests. C substitutes warming for the chemical mechanism of ozone destruction. Reduced ozone protection allows more harmful UVB radiation to reach the surface, increasing risks such as skin cancer and cataracts. EPA’s ozone science explanation (opens in a new tab) connects these steps.

Answer: C. HFCs were introduced as substitutes for ozone-depleting CFCs and HCFCs, but many are potent greenhouse gases. Ozone depletion and climate warming are different environmental effects. A incorrectly treats absence of ozone depletion as absence of climate impact; B reverses the distinction. A refrigerant’s ozone profile does not establish its warming potential. EPA’s fluorinated gas explanation (opens in a new tab) describes both effects.

Answer: B. EPA’s prohibition covers ozone-depleting refrigerants and their substitutes during maintenance, servicing, repair, and disposal. Certain substitutes are exempt in specified uses; lack of ozone depletion alone does not establish an exemption. EPA also permits limited “de minimis” releases during good-faith recovery or safe disposal efforts. That allowance does not create blanket permission to vent small amounts. See EPA’s venting prohibition and exceptions (opens in a new tab).

Answer: C. EPA does not require replacement or conversion of existing R-22 equipment. Reclaimed or previously produced R-22 can still support servicing. A and B confuse restrictions on new refrigerant supply with a ban on existing equipment. EPA’s homeowner guidance (opens in a new tab) explains the distinction.

Answer: B. EPA permits an employer or its authorized representative to purchase refrigerant when the employer provides the wholesaler with written evidence that it employs a properly certified technician. A overlooks the representative provision; C omits the required evidence. This purchasing arrangement does not establish the employee’s qualifications to perform refrigerant service. See EPA’s refrigerant sales requirements (opens in a new tab).

Answer: C. EPA says R-22 has no drop-in replacements: alternatives require component changes and must be acceptable for the intended use. Neither advertising nor ozone performance establishes compatibility. EPA’s retrofit explanation (opens in a new tab) supports evaluating the conversion rather than assuming interchangeability.

Answer: A. EPA’s GreenChill guidance explains that mixing different refrigerants can make reclamation more expensive because specialized separation is needed. Few reclaimers provide that capability, and some mixed material may require destruction. B incorrectly treats mixing as purification; C assumes a capability that cannot be taken for granted. The relevant Core principle is to avoid mixing different refrigerants. See the recovery discussion on printed page 22 of EPA’s GreenChill retrofit guide (opens in a new tab).

Answer: C. NIOSH lists asphyxia and abnormal heart rhythms among R-22 exposure effects, along with frostbite from liquid contact. Nonflammability describes one property; it does not establish that breathing the vapor or contacting the liquid is safe. A overlooks inhalation hazards, while B confuses flammability with cold injury. These findings are specific to R-22 in the NIOSH Pocket Guide entry for chlorodifluoromethane (opens in a new tab).