Identify the type of dermatitis

Case-A: 68y man who lays bricks and is exposed to several chemicals at work on a regular basis presents with a chronic pruritic rash on his left hand. Exam shows dry, erythematous skin with some fissures
Case-B: 55y man who recently bought a waist belt a few weeks ago presenting with a pruritic rash around his umbilicus. Exam shows a well demarcated erythematous rash with some superficial scabs formed after excessive scratching.

Which of the following statements is true?
1. Patient “A” has irritant” contact dermatitis while “B” has “allergic” contact dermatitis
2. Patient “A” has “allergic” contact dermatitis and “B” has “irritant” contact dermatitis.
3. Both patients have “allergic” contact dermatitis
4. Both patients have “irritant” contact dermatitis