The type of refrigeration equipment can determine how well a leak can be detected on-site. For example, open cases allow refrigerant leaks to disperse into the air quickly whereas closed-door refrigerators build the refrigerant gas up over time, and then release it upon the doors being opened. For example, Trader Joe’s stores have entirely open cases which makes it challenging to detect a leak in the public areas. Although our equipment did not detect leaks in these stores, this does not provide sufficient evidence of the absence of leaks.